bq2060 SBS v1.1-Compliant Gas Gauge IC Features General Description > The bq2060 SBS-Compliant Gas Gauge IC for battery pack or in-system installation maintains an accurate record of available charge in rechargeable batteries. The bq2060 monitors capacity and other critical battery parameters for NiCd, NiMH, Li-Ion, and lead-acid chemistries. The bq2060 uses a V-to-F converter with automatic offset error correction for charge and discharge counting. For voltage, temperature, and current reporting, the bq2060 uses an A-to-D converter. The onboard ADC also monitors individual cell voltages in a Li-Ion battery pack and allows the bq2060 to generate control signals that may be used in conjunction with a pack supervisor to enhance pack safety. Provides accurate measurement of available charge in NiCd, NiMH, Li-Ion, and lead-acid batteries > Supports SBS Smart Battery Data Specification v1.1 > Supports the 2-wire SMBus v1.1 interface with PEC or 1-wire HDQ16 > > Reports individual cell voltages > Provides 15-bit resolution for voltage, temperature, and current measurements > Measures charge flow using a V-to-F converter with offset of less than 16µV after calibration Monitors and provides control to charge and discharge FETs in Li-Ion protection circuit > Consumes less than 0.5mW operating > Drives a 4- or 5-segment LED display for remaining capacity indication > 28-pin 150-mil SSOP Pin Connections HDQ16 ESCL ESDA RBI REG VOUT VCC VSS DISP LED1 LED2 LED3 LED4 LED5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 The bq2060 supports the smart battery data (SBData) commands and charge-control functions. It communicates data using the system management bus (SMBus) 2-wire protocol or the Benchmarq 1-wire HDQ16 protocol. The data available include the battery’s remaining capacity, temperature, voltage, current, and remaining run-time predictions. The bq2060 provides LED drivers and a push-button input to depict remaining battery capacity from full to empty in 20% or 25% increments with a 4 or 5-segment display. The bq2060 works with an external EEPROM. The EEPROM stores the configuration information for the bq2060, such as the battery’s chemistry, self-discharge rate, rate compensation factors, measurement calibration, and design voltage and capacity. The bq2060 uses the programmable self-discharge rate and other compensation factors stored in the EEPROM to accurately adjust remaining capacity for use and standby conditions based on time, rate, and temperature. The bq2060 also automatically calibrates or learns the true battery capacity in the course of a discharge cycle from near full to near empty levels. The REG output regulates the operating voltage for the bq2060 from the battery cell stack using an external JFET. Pin Names SMBC SMBD VCELL4 VCELL3 VCELL2 VCELL1 SR1 SR2 SRC TS THON CVON CFC DFC 28-Pin 150-mil SSOP 28PN2060.eps HDQ16 Serial communication input/output ESCL Serial memory clock ESDA Serial memory data and address RBI Register backup input REG Regulator output VOUT EEPROM supply output VCC Supply voltage VSS Ground DISP Display control input LED1– LED5 LED display segment outputs SLUS035D–SEPTEMBER 2001 1 DFC Discharge FET control CFC Charge FET control VON trol Cell voltage divider con- THON Thermistor bias control TS Thermistor voltage input SRC Current sense input SR1– SR2 Charge-flow sense resistor inputs VCELL1– Single-cell voltage inputs VCELL4 SMBD SMBus data SMBC SMBus clock bq2060 DFC Pin Descriptions HDQ16 Output to control the discharge FET in the Li-Ion pack protection circuitry Serial communication input/output CFC Open-drain bidirectional communications port ESCL CVON Serial memory data and address THON Thermistor bias control output Output control for external FETs to connect the thermistor bias resistor during a temperature measurement Register backup input TS Input that provides backup potential to the bq2060 registers during periods of low operating voltage. RBI accepts a storage capacitor or a battery input. Thermistor voltage input Input connection for a thermistor to monitor temperature SRC REG Cell voltage divider control output Output control for external FETs to connect the cells to the external voltage dividers during cell voltage measurements Bidirectional pin used to transfer address and data to and from the bq2060 and the external nonvolatile configuration memory RBI Charge FET control output Output to control the charge FET in the Li-Ion pack protection circuitry Serial memory clock Output to clock the data transfer between the bq2060 and the external nonvolatile configuration memory ESDA Discharge FET control output Current sense voltage input Regulator output Input to monitor instantaneous current Output to control an n-JFET for VCC regulation to the bq2060 from the battery potential VOUT SR1– SR2 Input connections for a small value sense resistor to monitor the battery charge and discharge current flow Supply output Output that supplies power to the external EEPROM configuration memory VCC Supply voltage input VSS Ground DISP Display control input VCELL1– VCELL4 Single-cell voltage inputs Inputs that monitor the series element cell voltages SMBD SMBus data Open-drain bidirectional pin used to transfer address and data to and from the bq2060 Input that controls the LED drivers LED1–LED5 LED1– LED5 Sense resistor inputs LED display segment outputs SMBC Outputs that each may drive an external LED SMBus clock Open drain bidirectional pin used to clock the data transfer to and from the bq2060 2 bq2060 The VFC measures bipolar signals up to 250mV. The bq2060 detects charge activity when VSR = VSR2 – VSR1 is positive and discharge activity when VSR = VSR2 – VSR1 is negative. The bq2060 continuously integrates the signal over time using an internal counter. The fundamental rate of the counter is 6.25µVh. Functional Description General Operation The bq2060 determines battery capacity by monitoring the amount of charge input or removed from a rechargeable battery. In addition to measuring charge and discharge, the bq2060 measures battery voltage, temperature, and current, estimates battery self-discharge, and monitors the battery for low-voltage thresholds. The bq2060 measures charge and discharge activity by monitoring the voltage across a small-value series sense resistor between the battery’s negative terminal and the negative terminal of the battery pack. The available battery charge is determined by monitoring this voltage and correcting the measurement for environmental and operating conditions. Offset Calibration The bq2060 provides an auto-calibration feature to cancel the voltage offset error across SR1 and SR2 for maximum charge measurement accuracy. The calibration routine is initiated by issuing a command to ManufacturerAccess(). The bq2060 is capable of automatic offset calibration down to 6.25µV. Offset cancellation resolution is less than 1µV. Digital Filter The bq2060 does not measure charge or discharge counts below the digital filter threshold. The digital filter threshold is programmed in the EEPROM and should be set sufficiently high to prevent false signal detection with no charge or discharge flowing through the sense resistor. Figure 1 shows a typical bq2060-based battery pack application. The circuit consists of the LED display, voltage and temperature measurement networks, EEPROM connections, a serial port, and the sense resistor. The EEPROM stores basic battery pack configuration information and measurement calibration values. The EEPROM must be programmed properly for bq2060 operation. Table 10 shows the EEPROM memory map and outlines the programmable functions available in the bq2060. Voltage While monitoring SR1 and SR2 for charge and discharge currents, the bq2060 monitors the battery-pack potential and the individual cell voltages through the VCELL1–VCELL4 pins. The bq2060 measures the pack voltage and reports the result in Voltage(). The bq2060 can also measure the voltage of up to four series elements in a battery pack. The individual cell voltages are stored in the optional Manufacturer Function area. The bq2060 accepts an NTC thermistor (Semitec 103AT) for temperature measurement. The bq2060 uses the thermistor temperature to monitor battery pack temperature, detect a battery full charge condition, and compensate for self-discharge and charge/discharge battery efficiencies. The VCELL1–VCELL4 inputs are divided down from the cells using precision resistors, as shown in Figure 1. The maximum input for VCELL1–VCELL4 is 1.25V with respect to VSS. The voltage dividers for the inputs must be set so that the voltages at the inputs do not exceed the 1.25V limit under all operating conditions. Also, the divider ratios on VCELL1–VCELL2 must be half of that of VCELL3–VCELL4. To reduce current consumption from the battery, the CVON output may used to connect the divider to the cells only during measurement period. CVON is high impedance for 250ms (12.5% duty cycle) when the cells are measured, and driven low otherwise. See Table 1. Measurements The bq2060 uses a fully differential, dynamically balanced voltage-to-frequency converter (VFC) for charge measurement and a sigma delta analog-to-digital converter (ADC) for battery voltage, current, and temperature measurement. Voltage, current, and temperature measurements are made every 2–2.5 seconds, depending on the bq2060 operating mode. Maximum times occur with compensated EDV, mWh mode, and maximum allowable discharge rate. Any AtRate computations requested or scheduled (every 20 seconds) may add up to 0.5 seconds to the time interval. Current The SRC input of the bq2060 measures battery charge and discharge current. The SRC ADC input converts the current signal from the series sense resistor and stores the result in Current(). The full-scale input range to SBC is limited to ±250mV as shown in Table 2. Charge and Discharge Counting The VFC measures the charge and discharge flow of the battery by monitoring a small-value sense resistor between the SR1 and SR2 pins as shown in Figure 1. 3 bq2060 Figure 1. Battery Pack Application Diagram–LED Display and Series Cell Monitoring 4 bq2060 Table 1. Example VCELL1–VCELL4 Divider and Input Range Voltage Input VCELL4 VCELL3 VCELL2 VCELL1 Voltage Division Ratio 16 16 8 8 Temperature The TS input of the bq2060 in conjunction with an NTC thermistor measures the battery temperature as shown in Figure 1. The bq2060 reports temperature in Temperature(). THON may be used to connect the bias source to the thermistor when the bq2060 samples the TS input. THON is high impedance for 60ms when the temperature is measured, and driven low otherwise. Full-Scale Input (V) 20.0 20.0 10.0 10.0 Gas Gauge Operation General Table 2. SRC Input Range Sense Resistor (W) Full-Scale Input (A) 0.02 ±12.5 0.03 ±8.3 0.05 ±5.0 0.10 ±2.5 The operational overview in Figure 2 illustrates the gas gauge operation of the bq2060. Table 3 describes the bq2060 registers. The bq2060 accumulates a measure of charge and discharge currents and estimates self-discharge of the battery. The bq2060 compensates the charge current measurement for temperature and state-of-charge of the battery. The bq2060 also adjusts the self-discharge estimation based on temperature. The main counter RemainingCapacity() (RM) represents the available capacity or energy in the battery at any Figure 2. bq2060 Operational Overview 5 bq2060 given time. The bq2060 adjusts RM for charge, self-discharge, and leakage compensation factors. The information in the RM register is accessible through the communications ports and is also represented through the LED display. Discharge Count Register (DCR) The DCR register counts up during discharge, independent of RM. DCR can continue to count even after RM has counted down to 0. Prior to RM = 0, discharge activity, light discharge estimation and self-discharge increment DCR. After RM = 0, only discharge activity increments DCR. The bq2060 initializes DCR to FCC – RM when RM is within twice the programmed value in Near Full EE 0x55. The DCR initial value of FCC – RM is reduced by FCC/128 if SC = 0 (bit 2 in Control Mode) and is not reduced if SC = 1. DCR stops counting when the battery voltage reaches the EDV2 threshold on discharge. The FullChargeCapacity() (FCC) register represents the last measured full discharge of the battery. It is used as the battery’s full-charge reference for relative capacity indication. The bq2060 updates FCC when the battery undergoes a qualified discharge from nearly full to a low battery level. FCC is accessible through the serial communications ports. The Discharge Count Register (DCR) is a non-accessible register that only tracks discharge of the battery. The bq2060 uses the DCR register to update the FCC register if the battery undergoes a qualified discharge from nearly full to a low battery level. In this way, the bq2060 learns the true discharge capacity of the battery under system use conditions. Capacity Learning (FCC Update) and Qualified Discharge The bq2060 updates FCC with an amount based on the value in DCR if a qualified discharge occurs. The new value for FCC equals the DCR value plus the programmable nearly full and low battery levels, according to the following equation: Main Gas Gauge Registers FCC(new) = DCR(final) = DCR(initial) + measured discharge to EDV2 +(FCC´ BatteryLow%) RemainingCapacity() (RM) RM represents the remaining capacity in the battery. The bq2060 computes RM in either mAh or 10mWh depending on the selected mode. (1) where BatteryLow% = (value stored in EE 0x54) ¸ 2.56 On initialization, the bq2060 sets RM to 0. RM counts up during charge to a maximum value of FCC and down during discharge and self-discharge to 0. In addition to charge and self-discharge compensation, the bq2060 calibrates RM at three low-battery-voltage thresholds, EDV2, EDV1, and EDV0 and three programmable midrange thresholds VOC25, VOC50, and VOC75. This provides a voltage-based calibration to the RM counter. A qualified discharge occurs if the battery discharges from RM ≥ FCC - Near Full * 2 to the EDV2 voltage threshold with the following conditions: n DesignCapacity() (DC) n The DC is the user-specified battery full capacity. It is calculated from Pack Capacity EE 0x3a–0x3b and is represented in mAh or 10mWh. It also represents the full-battery reference for the absolute display mode. n n FullChargeCapacity() (FCC) FCC is the last measured discharge capacity of the battery. It is represented in either mAh or 10mWh depending on the selected mode. On initialization, the bq2060 sets FCC to the value stored in Last Measured Discharge EE 0x38–0x39. During subsequent discharges, the bq2060 updates FCC with the last measured discharge capacity of the battery. The last measured discharge of the battery is based on the value in the DCR register after a qualified discharge occurs. Once updated, the bq2060 writes the new FCC value to EEPROM in mAh to Last Measured Discharge. FCC represents the full battery reference for the relative display mode and relative state of charge calculations. n No valid charge activity occurs during the discharge period. A valid charge is defined as an input of 10mAh into the battery. No more than 256mAh of self-discharge and/or light discharge estimation occurs during the discharge period. The temperature does not drop below 5°C during the discharge period. The battery voltage reaches the EDV2 threshold during the discharge period and the voltage was less than the EDV2 threshold minus 256mV when the bq2060 detected EDV2. No midrange voltage correction occurs during the discharge period. FCC cannot be reduced by more than 256mAh or increased by more than 512mAh during any single update cycle. The bq2060 saves the new FCC value to the EEPROM within 4s of being updated. 6 bq2060 Table 3. bq2060 Register Functions Function Command Code SMBus HDQ16 SMBus Access Units ManufacturerAccess 0x00 0x00 read/write n/a RemainingCapacityAlarm 0x01 0x01 read/write mAh, 10mWh RemainingTimeAlarm 0x02 0x02 read/write minutes BatteryMode 0x03 0x03 read/write n/a AtRate 0x04 0x04 read/write mA, 10mW AtRateTimeToFull 0x05 0x05 read minutes AtRateTimeToEmpty 0x06 0x06 read minutes AtRateOK 0x07 0x07 read Boolean Temperature 0x08 0x08 read 0.1°K Voltage 0x09 0x09 read mV Current 0x0a 0x0a read mA AverageCurrent 0x0b 0x0b read mA MaxError 0x0c 0x0c read percent percent RelativeStateOfCharge 0x0d 0x0d read AbsoluteStateOfCharge 0x0e 0x0e read percent RemainingCapacity 0x0f 0x0f read mAh, 10mWh FullChargeCapacity 0x10 0x10 read mAh, 10mWh RunTimeToEmpty 0x11 0x11 read minutes AverageTimeToEmpty 0x12 0x12 read minutes AverageTimeToFull 0x13 0x13 read minutes ChargingCurrent 0x14 0x14 read mA ChargingVoltage 0x15 0x15 read mV Battery Status 0x16 0x16 read n/a CycleCount 0x17 0x17 read cycles DesignCapacity 0x18 0x18 read mAh, 10mWh DesignVoltage 0x19 0x19 read mV SpecificationInfo 0x1a 0x1a read n/a ManufactureDate 0x1b 0x1b read n/a SerialNumber 0x1c 0x1c read integer Reserved 0x1d–0x1f 0x1d - 0x1f - - ManufacturerName 0x20 0x20–0x25 read string string DeviceName 0x21 0x28–0x2b read DeviceChemistry 0x22 0x30–0x32 read string ManufacturerData 0x23 0x38–0x3b read string n/a Pack Status 0x2f (LSB) 0x2f (LSB) read/write Pack Configuration 0x2f (MSB) 0x2f (MSB) read/write n/a VCELL4 0x3c 0x3c read/write mV VCELL3 0x3d 0x3d read/write mV VCELL2 0x3e 0x3e read/write mV VCELL1 0x3f 0x3f read/write mV 7 bq2060 of the self-discharge estimation at a given temperature to the rate programmed for 25°C (Y% per day): Table 4. State of Charge Based on Low Battery Voltage Threshold EDV0 EDV1 EDV2 State of Charge in RM 0% 3% Battery Low % Self-Discharge Rate Temperature ( C) Temp < 10 1 Y% 4 1 Y% 2 10 ≤ Temp <20 20 ≤ Temp <30 per day per day Y% per day 30 ≤ Temp <40 2Y% per day End-of-Discharge Thresholds and Capacity Correction 40 ≤ Temp <50 4Y% per day 50 ≤ Temp <60 8Y% per day The bq2060 monitors the battery for three low-voltage thresholds, EDV0, EDV1, and EDV2. The EDV thresholds are programmed in EDVF/EDV0 EE 0x72–0x73, EMF/EDV1 EE 0x74–0x75, and EDV C1/C0 Factor/EDV2 EE 0x78–0x79. If the CEDV bit in Pack Configuration is set, automatic EDV compensation is enabled and the bq2060 computes the EDV0, EDV1, and EDV2 thresholds based on the values in EE 0x72–0x7d, 0x06, and the battery’s current discharge rate, temperature, capacity, and cycle count. The bq2060 disables EDV detection if Current() exceeds the Overload Current threshold programmed in EE 0x46 - EE 0x47. The bq2060 resumes EDV threshold detection after Current() drops below the overload current threshold. Any EDV threshold detected will be reset after 10mAh of charge are applied. 60 ≤ Temp <70 16Y% per day 70≤ Temp 32Y% per day The interval at which RM is reduced is given by the following equation, where n is the appropriate factor of 2 (n = 14 , 12 , 1, 2, . . . ): (2) Self - Discharge Update Time = 640·13500 256· n · (Y % per day) seconds The timer that keeps track of the self-discharge update time is halted whenever charge activity is detected. The timer is reset to zero if the bq2060 reaches the RemainingCapacity()=FullChargeCapacity() condition while charging. The bq2060 uses the thresholds to apply voltage-based corrections to the RM register according to Table 4. Example: If T = 35°C (n = 2) and programmed self-discharge rate Y is 2.5 (2.5% per day at 25°C), the bq2060 reduces RM by RM/256 (0.39%) every The bq2060 adjusts RM as it detects each threshold. If the voltage threshold is reached before the corresponding capacity on discharge, the bq2060 reduces RM to the appropriate amount as shown in Table 4. If RM reaches the capacity level before the voltage threshold is reached on discharge, the bq2060 prevents RM from decreasing until the battery voltage reaches the corresponding threshold. (3) 640·13500 256· n· (Y % per day) = 6750 seconds Self-Discharge The bq2060 estimates the self-discharge of the battery to maintain an accurate measure of the battery capacity during periods of inactivity. The algorithm for self-discharge estimation takes a programmed estimate for the expected self-discharge rate at 25°C stored in EEPROM and makes a fixed reduction to RM of an amount equal to RemainingCapacity()/256. The bq2060 makes the fixed reduction at a varying time interval that is adjusted to achieve the desired self-discharge rate. This method maintains a constant granularity of 0.39% for each self-discharge adjustment, which may be performed multiple times per day, instead of once per day with a potentially large reduction. The self-discharge estimation rate for 25°C is doubled for each 10 degrees above 25°C or halved for each 10 degrees below 25°C. The following table shows the relation Figure 3. Self-Discharge at 2.5%/Day @25C 8 bq2060 This means that a 0.39% reduction of RM will be made 12.8 times per day to achieve the desired 5% per day reduction at 35°C. For the midrange corrections to occur, the temperature must be in the range of 19°C to 31°C inclusive and the Current() and AverageCurrent() must both be between –64mA and 0. The bq2060 makes midrange corrections as shown in Table 5. Figure 3 illustrates how the self-discharge estimate algorithm adjusts RemainingCapacity() vs. temperature. Light Discharge or Suspend C u r r en t Compensation Charge Control The bq2060 can be configured in two ways to compensate for small discharge currents that produce a signal below the digital filter. First, the bq2060 can decrement RM and DCR at a rate determined by the value stored in Light Discharge Current EE 0x2b when it detects no discharge activity and the SMBC and SMBD lines are high. Light Discharge Current has a range of 44µA to 11.2mA. The bq2060 supports SBS charge control by broadcasting the ChargingCurrent() and ChargingVoltage() to the Smart Charger address. The bq2060 broadcasts the requests every 10s. The bq2060 updates the values used in the charging current and voltage broadcasts based on the battery’s state of charge, voltage, and temperature. The fast-charge rate is programmed in Fast-Charging Current EE 0x1a - 0x1b while the charge voltage is programmed in Charging Voltage EE 0x0a-0x0b. Charging Voltage and Current Broadcasts Alternatively, the bq2060 can be configured to disable the digital filter for discharge when the SMBC and SMBD lines are high. In this way, the digital filter will not mask the leakage current signal. The bq2060 is configured in this mode by setting the NDF bit in Control Mode. The bq2060 internal charge control is compatible with popular rechargeable chemistries. The primary charge-termination techniques include a change in temperature over a change in time (∆T/∆t) and current taper, for nickel-based and Li-Ion chemistries, respectively. The bq2060 also provides pre-charge qualification and a number of safety charge suspensions based on current, voltage, temperature, and state of charge. Midrange Capacity Corrections The bq2060 applies midrange capacity corrections when the VCOR bit is set in Pack Configuration. The bq2060 adjusts RM to the associated percentage at three different voltage levels VOC25, VOC50, and VOC75. The VOC values represent the open circuit battery voltage at which RM corresponds to the associated state of charge for each threshold. Alarm Broadcasts to Smart Charger and Host If any of the bits 8–15 in BatteryStatus() is set, the bq2060 broadcasts an AlarmWarning() message to the Host address. If any of the bits 12–15 in BatteryStatus() are set, the bq2060 also sends an AlarmWarning() message to the Smart Charger address. The bq2060 repeats the AlarmWarning() message every 10s until the bits are cleared. Threshold Associated State of Charge VOC25 25% Pre-Charge Qualification VOC50 50% VOC75 75% The bq2060 sets ChargingCurrent() to the pre-charge rate as programmed in Pre-Charge Current EE 0x1e-0x1f under the following conditions: Table 5. Midrange Corrections Condition Voltage() Result ≥ VOC75 and RelativeStateOfCharge() ≤ 63% RelativeStateOfCharge()→75% < VOC75 and RelativeStateOfCharge() ≥ 87% RelativeStateOfCharge()→75% ≥VOC50 and RelativeStateOfCharge() ≤ 38% RelativeStateOfCharge()→50% <VOC50 and RelativeStateOfCharge() ≥ 62% RelativeStateOfCharge()→50% ≥ VOC25 and RelativeStateOfCharge() ≤ 13% RelativeStateOfCharge()→25% < VOC25 and RelativeStateOfCharge() ≥ 37% RelativeStateOfCharge()→25% 9 bq2060 n n The over-temperature condition is cleared when Temperature() is equal to or below (Max T – 5°C). Voltage: The bq2060 requests the pre-charge charge rate when Voltage() drops below the EDV0 threshold (compensated or fixed EDVs). Once requested, a pre-charge rate remains until Voltage() increases above the EDVF threshold. The bq2060 also broadcasts the pre-charge value immediately after a device reset until Voltage() is above the EDVF threshold. This threshold is programmed in EDVF/EDV0 EE 0x72-0x73. n Temperature: The bq2060 requests the pre-charge rate when Temperature() is between 0°C and 5°C. Temperature() must rise above 5°C before the bq2060 requests the fast-charge rate. Charge Suspension The bq2060 may temporarily suspend charge if it detects a charging fault. A charging fault includes the following conditions. n n n Overcurrent: An overcurrent condition exists when the bq2060 measures the charge current to be more than the Overcurrent Margin above the ChargingCurrent(). Overcurrent Margin is programmed in EE 0x49. On detecting an overcurrent condition, the bq2060 sets the ChargingCurrent() to zero and sets the TERMINATE_CHARGE_ALARM bit in Battery Status(). The overcurrent condition and TERMINATE_ CHARGE_ALARM are cleared when the measured current drops below the ChargingCurrent plus the Overcurrent Margin. n Overcharge: An overcharge condition exists if the battery is charged more than the Maxmum Overcharge value after RM = FCC. Maximum Overcharge is programmed in EE 0x2e–0x2f. On detecting an overcharge condition, the bq2060 sets the ChargingCurrent() to zero and sets the OVER_CHARGED_ALARM, TERMINATE_CHARGE_ ALARM, and FULLY_CHARGED bits in BatteryStatus(). The bq2060 clears the OVER_ CHARGED_ALARM and TERMINATE_CHARGE_ ALARM when it detects that the battery is no longer being charged. The FULLY_CHARGED bit remains set and the bq2060 continues to broadcast zero charging current until RelativeStateOfCharge() is less than Fully Charged Clear% programmed in EE 0x4c.The counter used to track overcharge capacity is reset with 2mAh of discharge. Under-Temperature: An under-temperature condition exists if Temperature() < 0°C. On detecting an under temperature condition, the bq2060 sets ChargingCurrent() to zero. The bq2060 sets ChargingCurrent() to the appropriate pre-charge rate or fast-charge rate when Temperature() ≥ 0°C. Primary Charge Termination T h e b q 2 0 6 0 t er m in a t es c h a r g e if it d et ec t s a charge-termination condition. A charge-termination condition includes the following. Overvoltage: An overvoltage condition exists when the bq2060 measures the battery voltage to be more than the Overvoltage Margin above the ChargingVoltage() or a Li-Ion cell voltage has exceeded the overvoltage limit programmed in Cell Under-/Overoltage. Overvoltage Margin is programmed in EE 0x48 and Cell Under/Over Voltage in EE 0x4a (least significant nibble). On detecting an overvoltage condition, the bq2060 sets the ChargingCurrent() to zero and sets the TERMINATE_CHARGE_ALARM bit in BatteryStatus(). The bq2060 clears the TERMINATE_ CHARGE_ALARM bit when it detects that the battery is no longer being charged (DISCHARGING bit set in BatteryStatus()). The bq2060 continues to broadcast zero charging current until the overvoltage condition is cleared. The overvoltage condition is cleared when the measured battery voltage drops below the ChargingVoltage() plus the Overvoltage Margin or when the CVOV bit is reset. n ∆T/∆t: For ∆T/∆t, the bq2060 detects a change in temperature over many seconds. The ∆T/∆t setting is programmable in both the temperature step, DeltaT (1.6°C - 4.6°C), and the time step, DeltaT Time (20s-320s). Typical settings for 1°C/minute include 2°C/120s and 3°C/180s. Longer times are required for increased slope resolution. The DeltaT value is programmed in EE 0x45 (least significant nibble) and the Delta T Time in EE 0x4e. In addition to the ∆T/∆t timer, a hold-off timer starts when the battery is being charged at more than 255mA and the temperature is above 25°C. Until this timer expires, ∆T/∆t detection is suspended. If Current() drops below 256mA or Temperature() below 25°C, the hold-off timer resets and restarts only when the current and temperature conditions are met again. The hold-off timer is programmable (20s – 320s) with Holdoff Time value in EE 0x4f. Over-Temperature: An over-temperature condition exists when Temperature() is greater than or equal to the Max T value programmed in EE 0x45 (most significant nibble). On detecting an over-temperature condition, the bq2060 sets the ChargingCurrent() to zero and sets the OVER_TEMP_ALARM and TERMINATE_CHARGE_ ALARM bit in BatteryStatus() and the CVOV bit in Pack Status. n 10 Current Taper: For current taper, ChargingVoltage() must be set to the pack voltage desired during the constant-voltage phase of charging. The bq2060 detects a current taper termination when the pack voltage is greater than the voltage determined by Current Taper Qual Voltage in EE 0x4f and the charging current is below a threshold determined by Current Taper bq2060 Threshold in EE 0x4e, for at least 40s. The bq2060 uses the VFC to measure current for current taper termination. The current polarity must remain positive as measured by the VFC during this time. display timer expires. The bq2060 requires the DISP input to remain stable for a minimum of 250ms to detect the logic state. If the EDV0 bit is set, the bq2060 disables the LED display. The display is also disabled during a VFC calibration and should be turned off before entering low-power storage mode. Once the bq2060 detects a primary charge termination, the bq2060 sets the TERMINATE_CHARGE_ALARM and FULLY_CHARGED bits in BatteryStatus(), and sets the ChargingCurrent() to the maintenance charge rate as programmed in Maintenance Charging Current EE 0x1c–0x1d. On termination, the bq2060 also sets RM to a programmed percentage of FCC, provided that RelativeStateOfCharge() is below the desired percentage of FCC and the CSYNC bit in Pack Configuration EE 0x3f is set. If the CSYNC bit is not set and RelativeStateOfCharge() is less than the programmed percentage of FCC, the bq2060 clears the FULLY_CHARGED bit in BatteryStatus(). The programmed percentage of FCC, Fast Charge Termination %, is set in EE 0x4b. The bq2060 clears the FULLY_CHARGED bit when RelativeStateOfCharge() is less than the programmed Fully Charged Clear %. The bq2060 broadcasts the fast-charge rate when the FULLY_CHARGED bit is cleared and voltage and temperature permit. The bq2060 clears the TERMINATE_CHARGE_ALARM when it no longer detects that the battery is being charged or it no longer detects the termination condition. See Table 6 for a summary of BatteryStatus() alarm and status bit operation. Display Modes In relative mode, each LED output represents 20% or 25% of the RelativeStateOfCharge() value. In absolute mode, each LED output represents 20% or 25% of the AbsoluteStateOfCharge() value. Table 7 shows the display operation. In either mode, the bq2060 blinks the LED display if R em a in in g C a p a c it y ( ) is les s t h a n R em a in in g CapacityAlarm(). The display is disabled if EDV0 = 1. Secondary Protection for Li-Ion Undervoltage and overvoltage thresholds may be programmed in the byte value Cell Under/Over Voltage EE 0x4a to set a secondary level of protection for Lithium Ion cells. The bq2060 checks individual cell voltages for undervoltage and overvoltage conditions. The bq2060 displays the results in the Pack Status register and controls the state of the FET control outputs CFC and DFC. If any cell voltage is less than the VUV threshold, the bq2060 sets the CVUV bit in Pack Status and pulls the DFC pin to a logic low. If any cell voltage is greater than the VOV threshold, the bq2060 sets the CVOV bit in Pack Status and pulls the CFC pin to a logic low. Display Port General The display port drives a 4 or 5 LED bar-graph display. The display is activated by a logic signal on the DISP input. The bq2060 can display RM in either a relative or absolute mode with each LED representing a percentage of the full-battery reference. In relative mode, the bq2060 uses FCC as the full-battery reference; in absolute mode, it uses DC. Low-Power Storage Mode The bq2060 enters low-power mode 5– 8s after receiving the Enable Low-Power command. In this mode the bq2060 consumes less than 10µA. A rising edge on SMBC, SMBD, or HDQ16 restores the bq2060 to the full operating mode. The bq2060 does not perform any gas gauge functions during low-power storage mode. The DMODE bit in Pack Configuration programs the bq2060 for the absolute or relative display mode. The LED bit in Control Mode programs the 4 or 5 LED option. A 5th LED can be used with the 4 LED display option to show when the battery capacity is ≥ to 100%. Device Reset The bq2060 can be reset with commands over the HDQ16 or SMBus. Upon reset, the bq2060 initializes its internal registers with the information contained in the configuration EEPROM. The following command sequence initiates a full bq2060 reset: Activation The display may be activated at any time by a high-to-low transition on the DISP input. This is usually accomplished with a pullup resistor and a pushbutton switch. Detection of the transition activates the display and starts a four-second display timer. The timer expires and turns off the display whether DISP was brought low momentarily or held low indefinitely. Reactivation of the display requires that the DISP input return to a logic-high state and then transition low again. The second high-to-low transition must occur after the Write 0x4f to 0xff5a Write 0x7d to 0x0000 Write 0x7d to 0x0080 11 bq2060 Table 6. Alarm and Status Bit Summary Battery State Conditions Overcurrent C() ≥ CC() + Overcurrent Margin Overvoltage V() ≥ CV() + Overvoltage Margin VCELL1, 2, 3, or 4 > Cell Over Voltage CC() State and BatteryStatus Bits Set CC() = Fast or Pre-charge Current and/or Bits Cleared CC() = 0, TCA = 1 C() < CC() + Overcurrent Margin TCA = 1 DISCHARGING = 1 CC() = 0, CVOV = 1 V() < CV() + Overvoltage Margin Li-Ion cell voltage ≤ Cell Over Voltage Overtemperature T() ≥ Max T CC() = 0, OTA = 1, TCA = 1, CVOV = 1 T() ≤ Max T - 5°C or T() ≤ 43°C Capacity added after RM() = FCC() ≥ Maximum Overcharge CC() = 0, FC = 1 RSOC() < Fully Charged Cleared % Overcharge OCA = 1, TCA = 1 DISCHARGING = 1 T() < 0°C CC() = 0 0°C ≤ Τ() < 5°C, CC() = Pre-Charge Current T() ≥ 5°C, CC() = Fast-Charging Current CC() = Maintenance Charging Current, FC = 1 RSOC() < Fully Charged Cleared % TCA = 1 DISCHARGING = 1 or termination condition is no longer valid. V() ≤ EDV2 FD = 1 RSOC() > 20% V() ≤ EDV0 TDA = 1 V() > EDV0 VCELL1, 2, 3 or 4 < Cell Under Voltage TDA = 1, CVUV = 1 VCELL1, 2, 3, or 4 ≥ Cell Under Voltage Low capacity RM() < RCA() RCA = 1 RM() ≥ RCA() Low run-time ATTE() < RTA() RTA = 1 ATTE() ≥ RTA() Undertemperature Fast charge termination Fully discharged Overdischarged Note: ∆T/∆t or Current Taper C() = Current(), CV() = ChargingVoltage(), CC() = ChargingCurrent(), V() = Voltage(), T() = Temperature(), TCA = TERMINATE_CHARGE_ALARM, OTA = OVER_TEMPERATURE_ALARM, OCA = OVER_CHARGED_ALARM, TDA = TERMINATE_DISCHARGE_ALARM, FC = FULLY_CHARGED, FD = FULLY_DISCHARGED, RSOC() = RelativeStateOfCharge(). RM() = RemainingCapacity(), RCA = REMAINING_CAPACITY_ALARM, RTA = REMAINING_TIME_ALARM, ATTE() = AverageTimeToEmpty(), RTA() = RemainingTimeAlarm(), RCA() = RemainingCapacityAlarm(), FCC() = FullChargeCapacity. 12 bq2060 Table 7A. Display Mode Condition Relative or Absolute StateOfCharge() Table 7B. Display Mode 5 LED Display Option Condition Relative or Absolute StateOfCharge() 4 LED Display Option LED1 LED2 LED3 LED4 LED5 LED1 LED2 LED3 LED4 EDV0 = 1 OFF OFF OFF OFF OFF EDV0 = 1 OFF OFF OFF OFF <20% ON OFF OFF OFF OFF <25% ON OFF OFF OFF ≥20%, <40% ON ON OFF OFF OFF ≥25%, <50% ON ON OFF OFF ≥40%, <60% ON ON ON OFF OFF ≥50%, <75% ON ON ON OFF ≥60%, <80% ON ON ON ON OFF ≥75% ON ON ON ON ≥80% ON ON ON ON ON SMBus Protocol Communication The bq2060 supports the following SMBus protocols: The bq2060 includes two types of communication ports: SMBus and HDQ16. The SMBus interface is a 2-wire bidirectional protocol using the SMBC (clock) and SMBD (da t a ) p i ns . T he H D Q 1 6 i nte r f a c e i s a 1 - w ir e bidirectional protocol using the HDQ16 pin. All three communication lines are isolated from VCC and may be pulled-up higher than VCC. Also, the bq2060 will not pull these lines low if VCC to the part is zero . HDQ16 should be pulled down with a 100KΩ resistor if not used. n Read Word n Write Word n Read Block A processor acting as the bus master uses the three protocols to communicate with the bq2060. The bq2060 acting as the bus master uses the Write Word protocol. The SMBD and SMBC pins are open drain and require external pullup resistors. The communication ports allow a host controller, an SMBus compatible device, or other processor to access the memory registers of the bq2060. In this way a system can efficiently monitor and manage the battery. SMBus Packet Error Checking The bq2060 supports Packet Error Checking as a mechanism to confirm proper communication between it and another SMBus device. Packet Error Checking requires that both the transmitter and receiver calculate a Packet Error Code (PEC) for each communication message. The device that supplies the last byte in the communication message appends the PEC to the message. The receiver compares the transmitted PEC to its PEC result to determine if there is a communication error. SMBus The SMBus interface is a command-based protocol. A processor acting as the bus master initiates communication to the bq2060 by generating a START condition. A START condition consists of a high-to-low transition of the SMBD line while the SMBC is high. The processor then sends the bq2060 device address of 0001011 (bits 7–1) plus a R/W bit (bit 0) followed by an SMBus command code. The R/W bit and the command code instruct the bq2060 to either store the forthcoming data to a register specified by the SMBus command code or output the data from the specified register. The processor completes the access with a STOP condition. A STOP condition consists of a low-to-high transition of the SMBD line while the SMBC is high. With SMBus, the most significant bit of a data byte is transmitted first. PEC Protocol The bq2060 can receive or transmit data with or without PEC. Figure 4 shows the communication protocol for the Read Word, Write Word, and Read Block messages without PEC. Figure 5 includes PEC. In the Write Word protocol, the bq2060 receives the PEC after the last byte of data from the host. If the host does not support PEC, the last byte of data is followed by a STOP condition. After receipt of the PEC, the bq2060 compares the value to its calculation. If the PEC is correct, the bq2060 responds with an ACKNOWLEDGE. If it is not correct, the bq2060 responds with a NOT ACKNOWLEDGE and sets an error code. In some instances, the bq2060 acts as the bus master. This occurs when the bq2060 broadcasts charging requirements and alarm conditions to device addresses 0x12 (SBS Smart Charger) and 0x10 (SBS Host Controller.) 13 bq2060 1 S 7 Battery Address 0001011 1 1 8 1 8 1 8 1 1 0 A Command Code A Data byte low A Data byte high A P Write Word 1 S 7 Battery Address 0001011 1 1 8 1 1 7 1 1 0 A Command Code A S Battery Address 1 A 8 1 8 1 Data byte low A Data byte high A P Host Processor Read Word 1 S 7 Battery Address 0001011 1 1 8 1 1 7 1 1 0 A Command Code A S Battery Address 1 A bq2060 8 1 8 1 8 1 8 1 1 Byte Count =N A Data byte 1 A Data byte 2 A Data byte N A P A – ACKNOWLEDGE A – NOT ACKNOWLEDGE S – START P – STOP Block Read FG2060HCP.eps Figure 4. SMBus Communication Protocol without PEC 1 S 7 Battery Address 0001011 1 1 8 1 8 1 8 1 0 A Command Code A Data byte low A Data byte high A 8 1 PEC A 1 P Write Word 1 S 7 Battery Address 0001011 1 1 8 1 1 7 1 1 0 A Command Code A S Battery Address 1 A 8 1 8 1 8 1 1 Data byte low A Data byte high A PEC A P Host Processor bq2060 Read Word 1 S 7 Battery Address 0001011 1 1 8 1 1 7 1 1 0 A Command Code A S Battery Address 1 A A – ACKNOWLEDGE A – NOT ACKNOWLEDGE S – START P – STOP 8 1 8 1 8 1 8 1 8 1 1 Byte Count =N A Data byte 1 A Data byte 2 A Data byte N A PEC A P Block Read FG2060PEC.eps Figure 5. SMBus Communication Protocol with PEC 14 bq2060 In the Read Word and Block Read, the host generates an ACKNOWLEDGE after the last byte of data sent by the bq2060. The bq2060 then sends the PEC and the host acting as a master-receiver generates a NOT ACKNOWLEDGE and a STOP condition. A bit transmission consists of three distinct sections. The first section starts the transmission by either the host or the bq2060 taking the HDQ16 pin to a logic-low state for a period t S T R H ; B . The next section is the actual data-transmission, where the data bit is valid by the time, tDSU;B after the negative edge used to start communication. The data bit is held for a period tDH;DV to allow the host processor or bq2060 to sample the data bit. PEC Calculation The basis of the PEC calculation is an 8-bit Cyclic Redundancy Check (CRC-8) based on the polynomial C(X) = X8 + X2 + X1 + 1. The PEC calculation includes all bytes in the transmission, including address, command, and data. The PEC calculation does not include ACKNOWLEDGE, NOT ACKNOWLEDGE, START, STOP, and Repeated START bits. The final section is used to stop the transmission by returning the HDQ16 pin to a logic-high state by at least the time tSSU;B after the negative edge used to start communication. The final logic-high state should be until a period tCYCH;B to allow time to ensure that the bit transmission was stopped properly. For example, the host requests RemainingCapacity() from the bq2060. This includes the host following the Read Word protocol. The bq2060 calculates the PEC based on the following 5 bytes of data, assuming the remaining capacity of the battery is 1001mAh. n Battery Address with R/W = 0: 0x16 n Command Code for RemainingCapacity(): 0x0f n Battery Address with R/W = 1: 0x17 n RemainingCapacity(): 0x03e9 If a communication error occurs (e.g., tCYCB > 250µs), the host sends the bq2060 a BREAK to reinitiate the serial interface. The bq2060 detects a BREAK when the HDQ16 pin is in a logic-low state for a time t B or greater. The HDQ16 pin is then returned to its normal ready-high logic state for a time tBR. The bq2060 is then ready to receive a command from the host processor. The HDQ16 pin is open drain and requires an external pullup resistor. Command Codes For 0x160f17e903, the bq2060 transmits a PEC of 0xe8 to the host. The SMBus Command Codes are in ( ), the HDQ16 in [ ]. Temperature(), Voltage(), Current(), and AverageCurrent(), performance specifications are at regulated VCC (VRO) and a temperature of 0–70°C. PEC Enable in Master Mode PEC for master mode broadcasts to the charger, host, or both can be enabled/disabled with the combination of the bits HPE and CPE in Control Mode. ManufacturerAccess() (0x00); [0x00–0x01] Description: This function provides writable command codes to control the bq2060 during normal operation and pack manufacture. These commands can be ignored if sent within one second after a device reset. The following list of commands are available. SMBus On and Off State The bq2060 detects whether the SMBus enters the Off State” by monitoring the SMBC and SMBD lines. When both signals are continually low for at least 2.5s, the bq2060 detects the Off State. When the SMBC and SMBD lines go high, the bq2060 detects the On State and can begin communication within 1ms. One-MΩ pulldown resistors on SMBC and SMBD are recommended for reliable Off State detection. 0x0618 Enable Low-Power Storage Mode: Activates the low-power storage mode. The bq2060 enters the storage mode after a 5–8s delay. The bq2060 accepts other commands to ManufacturerAccess() during the delay before entering low-power storage mode. The LEDs must be off before entering the low-power storage mode as the display state remains unchanged. During the delay following the low-power storage command, a VFC Calibration command may be issued. HDQ16 The HDQ16 interface is a command-based protocol. (See Figure 6.) A processor sends the command code to the bq2060. The 8-bit command code consists of two fields, the 7-bit HDQ16 command code (bits 0–6) and the 1-bit R/W field. The R/W field directs the bq2060 either to n Store the next 16 bits of data to a specified register or n Output 16 bits of data from the specified register The bq2060 clears the ManufacturerAccess() command within 900ms of acknowledging the Enable Low-Power Storage command. The VFC Calibration command must be sent 900–1600ms after SMBus acknowledgment of the Enable Low-Power Storage command. In this case, the bq2060 delays entering storage mode until the calibration process completes and the bq2060 stores the new calibration values in EEPROM. With HDQ16, the least significant bit of a data byte (command) or word (data) is transmitted first. 15 bq2060 0x062b SEAL Command: Instructs the bq2060 to restrict access to those functions listed in Table 3. Note: The SEAL Command does not change the state of the SEAL bit in Pack Configuration in EEPROM. The bq2060 completes the seal function and clears ManufacturerAccess() within 900ms of acknowledging the command. error. The bq2060 caps the calibration time at one hour in the event of calibrating zero offset error. The VFC calibration can be done as the last step in a battery pack test procedure since the calibration can complete automatically after removal from a test setup. The bq2060 clears ManufacturerAccess() within 900ms and starts calibration within 3.2s of acknowledging the command. 0x064d Charge Synchronization: Instructs the bq2060 to update RM to a percentage of FCC as defined in Fast Charge Termination %. The bq2060 updates RM and clears ManufacturerAccess() within 900ms of acknowledging the command. 0x0660 Stop VFC Calibration: Instructs the bq2060 to abort a VFC calibration procedure. If aborted, the bq2060 disables offset correction. The bq2060 stops calibration within 20ms of acknowledging the command. 0x0653 Enable VFC Calibration: Instructs the unsealed bq2060 to begin VFC calibration. With this command the bq2060 deselects the SR1 and SR2 inputs and calibrates for IC offset only. It is best to avoid charge or discharge currents through the sense resistor during this calibration process. 0x0606 Program EEPROM: Instructs the unsealed bq2060 to connect the SMBus to the EEPROM I2C bus. The bq2060 applies power to the EEPROM within 900ms of acknowledging the command. After issuing the program EEPROM command, the bq2060 monitoring functions are disabled until the I2C bus is disconnected. The bq2060 disconnects the I2C bus when it detects that the Battery Address 0x16 is sent over the SMBus. The Battery Address 0x16 to disconnect the I2C bus should not be sent until 10ms after the last write to the EEPROM. 0x067e Alternate VFC Calibration: Instructs the unsealed bq2060 to begin VFC calibration. With this command the bq2060 does not deselect the SR1 and SR2 inputs and calibrates for IC and PCB offset. During this procedure no charge or discharge currents Example: The following sequence of actions is an example of how to use the ManufacturerAccess() commands in an efficient manner to take a battery pack that has completed all testing and calibration except for VFC calibration and to make it ready for shipment in the SEALED state and in low-power storage mode: 1. Complete testing and calibration with desired final values stored in EEPROM. This process includes setting the SEAL bit in Pack Configuration. Sending a reset command to the bq2060 during test ensures that RAM values correspond to the final EEPROM values During VFC calibration, the bq2060 disables the LED display and accepts only the Stop VFC Calibration and the SEAL Command to ManufacturerAccess(). The bq2060 disregards all other commands. SMBus communication should be kept to a minimum during VFC calibration to reduce the noise level and allow a more accurate calibration. Once started, the VFC calibration procedure completes automatically. When complete, the bq2060 saves the calibration values in EEPROM. The calibration normally takes about 8 to 10 minutes. The calibration time is inversely proportional to the bq2060 VFC (and PCB) offset Send Host to bq2060 HDQ Command Code Break Send Host to bq2060 or Receive from bq2060 16 bit Data tRR R/W MSB Bit7 LSB Bit0 tRSPS Start-bit Address-Bit/ Data-Bit Stop-Bit TD2060CE.eps Figure 6. HDQ16 Communication Example 16 bq2060 2. If the initial value of RemainingCapacity() must be non-zero, the desired value may be written to Command 0x26 with the pack unsealed. A reset sent after this step resets RM to zero. 3. Issue the Enable Low-Power Storage Mode command. 4. Within 900–1600ms after sending the Enable Low-Power command, issue the Enable VFC Calibration command. This delays the low-power storage mode until after VFC calibration completion. 5. Issue the SEAL Command subsequent to the VFC Calibration command. The bq2060 must receive the SEAL Command before VFC calibration completes. The bq2060 resets the OCE bit in Pack Status when calibration begins and sets the bit when calibration successfully completes. Input/Output: Unsigned integer—value below which Low Capacity messages are sent. Battery Modes CAPACITY_MODE CAPACITY_MODE bit = 0 bit = 1 Units mAh @ C/5 10mWh @ P/5 Range 0–65,535mAh 0–65,535 10mWh Granularity Not applicable Accuracy See RemainingCapacity() RemainingTimeAlarm() (0x02); [0x02] Description: Sets or gets the remaining time alarm value. Whenever the AverageTimeToEmpty() falls below the remaining time value, the bq2060 sends AlarmWarning() messages to the SMBus Host with the REMAINING_TIME_ALARM bit set. A remaining time value of 0 effectively disables this alarm. The bq2060 initially sets the remaining time value to the Remaining Time Alarm value programmed in EE 0x02 - 0x03. The remaining time value remains unchanged until altered by the RemainingTimeAlarm() function. After VFC calibration completes automatically, the bq2060 saves the VFC offset cancellation values in EEPROM and enters the low-power storage mode in about 20s. In addition, the bq2060 is sealed, allowing access as defined in Table 3 only. Purpose: The ManufacturerAccess() function provides the system host access to bq2060 functions that are not defined by the SBD. Purpose: The RemainingTimeAlarm() function can be used by systems that want to adjust when the remaining time alarm warning is sent. The remaining time value can be read to verify the value in use by the bq2060’s RemainingTimeAlarm(). SMBus Protocol: Read or Write Word Input/Output: Word RemainingCapacityAlarm() (0x01); [0x01] SMBus Protocol: Read or Write Word Description: Sets or gets the low-capacity threshold value. Whenever the RemainingCapacity() falls below the low capacity value, the bq2060 sends AlarmWarning() messages to the SMBus Host with the REMAINING_CAPACITY_ALARM bit set. A low-capacity value of 0 disables this alarm. The bq2060 initially sets the low-capacity value to Remaining Capacity Alarm value programmed in EE 0x04 - 0x05. The low-capacity value remains unch a n g e d unt i l a l t e r e d by t he R em a in in g CapacityAlarm() function. The low-capacity value may be expressed in either current (mA) or power (10mWh) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. Input/Output: Unsigned integer—the point below which remaining time messages are sent. Units: minutes Range: 0 to 65,535 minutes Granularity: Not applicable Accuracy: see AverageTimeToEmpty() BatteryMode() (0x03); [0x03] Description: This function selects the various battery operational modes and reports the battery’s mode and requests. Purpose: The RemainingCapacityAlarm() function can be used by systems that know how much power they require to save their operating state. It enables those systems to more finely control the point at which they transition into suspend or hibernate state. The low-capacity value can be read to verify the value in use by the bq2060’s low capacity alarm. Defined modes include n n SMBus Protocol: Read or Write Word 17 Whether the battery’s capacity information is specified in mAh or 10mWh (CAPACITY_MODE bit) Whether the ChargingCurrent() and ChargingVoltage() values are broadcast to the Smart Battery Charger bq2060 when the bq2060 detects the battery requires charging (CHARGER_MODE bit) n least significant bit (bits 0–7) which is read only. The bq2060 forces bits 0–6 to zero and prohibits writes to bit 7. Whether all broadcasts to the Smart Battery Charger and Host are disabled Table 8 summarizes the meanings of the individual bits in the BatteryMode() word and specifies the default values, where applicable, are noted. The defined request condition is the battery requesting a conditioning cycle (RELEARN_FLAG). INTERNAL_CHARGE_CONTROLLER bit is not used by the bq2060. Purpose: The CAPACITY_MODE bit allows power management systems to best match their electrical characteristics with those reported by the battery. For example, a switching power supply represents a constant power load, whereas a linear supply is better represented by a constant current model. The CHARGER_MODE bit allows a SMBus Host or Smart Battery Charger to override the Smart Battery’s desired charging parameters by d i sa b l i n g t he b q 2 0 6 0 ’s br o a d c as t s . T h e R ELEARN_FLAG bit allows the bq2060 to request a conditioning cycle. PRIMARY_BATTERY_SUPPORT bit is not used by the bq2060. RELEARN_FLAG bit set indicates that the bq2060 is requesting a capacity relearn cycle for the battery. The bq2060 sets the RELEARN_FLAG on a full reset and if it detects 20 cycle counts without an FCC update. The bq2060 clears this flag after a learning cycle has been completed. CHARGE_CONTROLLER_ENABLED bit is not used by the bq2060. The bq2060 forces this bit to zero. SMBus Protocol: Read or Write Word PRIMARY_BATTERY bit is not used by the bq2060. The bq2060 forces this bit to zero. Input/Output: Unsigned integer —bit mapped— see below. ALARM_MODE bit is set to disable the bq2060’s ability to master the SMBus and send AlarmWarning() messages to the SMBus Host and the Smart Battery Charger. When set, the bq2060 does NOT master the SMBus, and AlarmWarning() messages are NOT sent to the SMBus Host and the Smart Battery Charger for a period of no more than 65s and no less than 45s. When cleared (default), the Smart Battery sends the AlarmWarning() Units: not applicable Range: 0–1 Granularity: not applicable Accuracy: not applicable The BatteryMode() word is divided into two halves, the most significant bit (bits 8–15) which is read/write and the Table 8. Battery Mode Bits and Values Battery Mode() Bits INTERNAL_CHARGE_CONTROLLER PRIMARY_BATTERY_SUPPORT Reserved Bits Used 0 1 2–6 Format Read only bit flag Read only bit flag RELEARN_FLAG 7 Read only bit flag CHARGE_CONTROLLER_ENABLED PRIMARY_BATTERY Reserved 8 9 10–12 R/W bit flag R/W bit flag ALARM_MODE 13 R/W bit flag CHARGER_MODE 14 R/W bit flag CAPACITY_MODE 15 R/W bit flag 18 Allowable Values 0—Battery OK 1—Relearn cycle requested 0—Enable alarm broadcast (default) 1—Disable alarm broadcast 0—Enable charging broadcast (default) 1—Disable charging broadcast 0—Report in mA or mAh (default) 1—Report in 10mW or 10mWh bq2060 messages to the SMBus Host and the Smart Battery Charger any time an alarm condition is detected. n n n The bq2060 polls the ALARM_MODE bit at least every 150ms. Whenever the ALARM_MODE bit is set, the bq2060 resets the bit and starts or restarts a 55s (nominal) timer. After the timer expires, the bq2060 automatically enables alarm broadcasts to ensure that the accidental deactivation of broadcasts does not persist. To prevent the bq2060 from becoming a master on the SMBus, an SMBus host must therefore continually set this bit at least once per 50s to keep the bq2060 from broadcasting alarms. The condition of the ALARM-MODE bit does NOT affect the operation or state of the CHARGER_MODE bit which is used to prevent broadcasts of ChargingCurrent() and ChargingVoltage() to the Smart Battery Charger. n RemainingCapacity() n FullChargeCapacity() n DesignCapacity() AtRateTimeToFull() n RunTimeToEmpty() n AverageTimeToEmpty() n AverageTimeToFull() n Remaining Time Alarm() n BatteryStatus() Purpose: Since the AtRate() function is the first half of a two-function call-set, it is followed by the second function of the call-set that calculates and returns a value based on the AtRate value and the battery’s present state. A delay of up to 1.3s is required after writing AtRate() before the bq2060 can acknowledge the requested AtRate function. n Note 1: The following functions are changed to accept or return values in mA/mAh or 10mW/10mWh depending on the CAPACITY_MODE bit: AtRate() AtRateTimeToEmpty() n Description: The AtRate() function is the first half of a two-function call-set used to set the AtRate value used in calculations made by the AtRateTimeToFull(), AtRateTimeToEmpty(), and AtRateOK() functions. The AtRate value may be expressed in either current (mA) or power (10mW) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. CAPACITY_MODE bit indicates if capacity information is reported in mA/mAh or 10mW/10mWh. When set, the bq2060 reports capacity information in 10mW/10mWh as appropriate. When cleared, the bq2060 reports capacity information in mA/mAh as appropriate. The CAPACITY_MODE bit defaults to a cleared state within 130ms after the bq2060 detects the SMBus Off-State. n n AtRate() (0x04); [0x04] CHARGER_MODE bit enables or disables the bq2060’s t ra n smi s s i o n of C har g i ng C ur r e n t ( ) and ChargingVoltage() messages to the Smart Battery Charger. When set, the bq2060 does NOT transmit ChargingCurrent() and ChargingVoltage() values to the Smart Battery Charger. When cleared, the bq2060 transmits the ChargingCurrent() and ChargingVoltage() v a l u e s t o t he S m a r t B a tte r y C ha r g er. T h e CHARGER_MODE bit defaults to a cleared state within 130ms after the bq2060 detects the SMBus Off-State. RemainingCapacityAlarm() AtRateOK() The bq2060 updates the non-AtRate related register values within 3s of changing the state of the CAPACITY_MODE bit. The AtRate() values will be updated after the next AtRate value is written to the bq2060 (or after the next 20s scheduled refresh calculation). The ALARM_MODE bit defaults to a cleared state within 130ms after the bq2060 detects the SMBus Off-State. n n n n When the AtRate() value is positive, the AtRateTimeToFull() function returns the predicted time to full-charge at the AtRate value of charge. When the AtRate() value is negative, the AtRateTimeToEmpty() function returns the predicted operating time at the AtRate value of discharge. When the AtRate() value is negative, the AtRateOK() function returns a Boolean value that predicts the battery’s ability to supply the AtRate value of additional discharge energy (current or power) for 10 seconds. The default value for AtRate() is zero. Writing AtRate() values over the HDQ16 serial port does NOT trigger a re-calculation of AtRateTimeToFull(), AtRateTimeToEmpty(), and AtRateOK() functions. Note 2: The following functions are calculated on the basis of capacity and may be calculated differently depending on the CAPACITY_MODE bit: It is recommended that AtRate() requests should be limited to one request every 4s. 19 bq2060 SMBus Protocol: Read or Write Word AtRateTimeToEmpty() (0x06); [0x06] Input/Output: Signed integer—charge or discharge; the AtRate() value is positive for charge, negative for discharge, and zero for neither (default). Description: Returns the predicted remaining operating time if the battery is discharged at the AtRate() value. Units Charge Range Discharge Range Granularity Accuracy Purpose: The AtRateTimeToEmpty() function is part of a two-function call-set used to determine the remaining operating time at the AtRate()value. The bq2060 updates AtRateTimeToEmpty() within 1.3s after the SMBus Host sets the AtRate() value. If read before this delay, the command is No Acknowledged, and the error code in BatteryStatus is set to not ready. The bq2060 automatically updates AtRateTimeToEmpty() based on the AtRate() value every 20s. Battery Mode CAPACITY_MODE CAPACITY_MODE bit = 0 bit = 1 mA 10mW 1–32,767mA 1–32,768 10mW -1– -32,768mA -1– -32,768 10mW 1 Unit NA SMBus Protocol: Read Word Output: AtRateTimeToFull() (0x05);[0x05] Unsigned integer — estimated operating time left. Description: Returns the predicted remaining time to fully charge the battery at the AtRate( ) value (mA). Units: minutes Range: 0 to 65,534 min Granularity: 2 min or better Purpose: T h e A t Ra te Ti m e To F ul l ( ) f unc ti o n i s p a r t of a two-function call-set used to determine the predicted remaining charge time at the AtRate value in mA. The bq2060 updates AtRateTimeToFull() within 1.3s after the SMBus Host sets the AtRate value. If read before this delay, the command is No Acknowledged and the error code in BatteryStatus is set to not ready. The bq2060 automatically updates AtRateTimeToFull() based on the AtRate() value every 20s. Accuracy: -0, +MaxError() * FullChargeCapacity/|AtRate()| Invalid Data Indication: 65,535 indicates the battery is not being discharged. AtRateOK() (0x07); [0x07] Description: Returns a Boolean value that indicates whether or not the battery can deliver the AtRate( )value of additional energy for 10 seconds (Boolean). If the AtRate value is zero or positive, the AtRateOK() function ALWAYS return-true. SMBus Protocol: Read Word Output: Unsigned integer—predicted time in minutes to fully charge the battery. Purpose: The AtRateOK() function is part of a two-function call-set used by power management systems to determine if the battery can safely supply enough energy for an additional load. The bq2060 updates AtRateOK() within 1.3s after the SMBus Host sets the AtRate( ) value. If read before this delay, the command is No Acknowledged, and the error code in BatteryStatus is set to not ready. The bq2060 automatically updates AtRateOK() based on the At Rate() value every 20s. Units: minutes Range: 0 to 65,534 min Granularity: 2 min or better Accuracy: ±MaxError() * FullChargeCapacity()/|AtRate()| SMBus Protocol: Read Word Invalid Data Indication: 65,535 indicates the battery is not being charged. Output: Boolean—indicates if the battery can supply the additional energy requested. 20 bq2060 Units: Boolean Current() (0x0a); [0x0a] Range: TRUE, FALSE Description: Returns the current being supplied (or accepted) through the battery’s terminals (mA). Granularity: not applicable Accuracy: not applicable Purpose: The Current() function provides a snapshot for the power management system of the current flowing into or out of the battery. This information is of particular use in power-management systems because they can characterize individual devices and tune their operation to actual system power behavior. Temperature() (0x08); [0x08] Description: Returns the temperature (K) measured by the bq2060. Purpose: The Temperature() function provides accurate cell temperatures for use by battery chargers and thermal management systems. A battery charger can use the temperature as a safety check. Thermal management systems may use the temperature because the battery is one of the largest thermal sources in a system. SMBus Protocol: Read Word Output: Signed integer—charge/discharge rate in mA increments—positive for charge, negative for discharge. SMBus Protocol: Read Word Units: mA Output: Range: (± 250mV/RS) mA Unsigned integer—cell temperature in tenth-degree Kelvin increments. Granularity: 0.038mV/RS (integer value) Units: 0.1°K Accuracy: ±1mV/RS (after calibration) Range: 0 to +6553.5°K {real range} AverageCurrent() (0x0b); [0x0b] Granularity: 0.1°K Description: Returns a value that approximates a one-minute rolling average of the current being supplied (or accepted) t h r ou g h t h e b a t t er y ’s t er m in a ls ( m A ) . The AverageCurrent() function will return meaningful values during the battery’s first minute of operation. Accuracy: ±1.5°K (from ideal 103AT thermistor performance, after calibration) Voltage() (0x09); [0x09] Description: Returns the cell-pack voltage (mV). Purpose: The AverageCurrent() function provides the average current flowing into or out of the battery for the power management system. Purpose: The Voltage() function provides power management systems with an accurate battery terminal voltage. Power management systems can use this voltage, along with battery current information, to characterize devices they control. This ability helps enable intelligent, adaptive power-management systems. SMBus Protocol: Read Word Output: Signed integer—charge/discharge rate in mA increments—positive for charge, negative for discharge. SMBus Protocol: Read Word Units: mA Output: Range: (± 250mV/RS) mA Unsigned integer—battery terminal voltage in mV. Granularity: 0.038mV/RS (integer value) Units: mV Accuracy: ±1mV/RS (after calibration) Range: 0 to 20,000 mV MaxError() (0x0c); [0x0c] Granularity: 1mV Description: Returns the expected margin of error (%) in the state of charge calculation. For example, when MaxError() re- Accuracy: ±0.65% (after calibration) 21 bq2060 turns 10% and RelativeStateOfCharge() returns 50%, the Relative StateOfCharge() is more likely between 50 and 60%. The bq2060 sets MaxError() to 100% on a full reset. The bq2060 sets MaxError() to 2% on completion of a learning cycle, unless the bq2060 limits the learning cycle to the +512/-256mAh maximum adjustment values. If the learning cycle is limited, the bq2060 sets MaxError() to 8% unless MaxError() was already below 8%. In this case MaxError() does not change. The bq2060 increments MaxError() by 1% after four increments of CycleCount() without a learning cycle. AbsoluteStateOfCharge()(0x0e); [0x0e] Description: Returns the predicted remaining battery capacity expressed as a percentage of DesignCapacity() (%). Note that AbsoluteStateOfCharge() can return values greater than 100%. Purpose: The AbsoluteStateOfCharge() function is used to estimate the amount of charge remaining in the battery relative to the nominal or DesignCapacity(). If voltage-based corrections are applied to the coulomb counter, MaxError() is set to 25%. SMBus Protocol: Read Word Output: Purpose: The MaxError() function has real value in two ways: first, to give the user a confidence level about the state of charge and second, to give the power management system information about how aggressive it should be, particularly as the battery nears the end of its life. Unsigned integer—percent of remaining capacity. Units: % Range: 0 to 100+% SMBus Protocol: Read Word Granularity: 1% Output: Accuracy: -0, +MaxError() RemainingCapacity() (0x0f); [0x0f] Unsigned integer—percent uncertainty for selected information. Description: Returns the predicted charge or energy remaining in the battery. The RemainingCapacity() value is expressed in either charge (mAh at a C/5 discharge rate) or energy (10mWh at a P/5 discharge rate) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. Units: % Range: 2 to 100% Granularity: 1% Accuracy: not applicable Purpose: The RemainingCapacity() function returns the battery’s remaining capacity. This information is a numeric indication of remaining charge or energy given by the Absolute or Relative StateOfCharge() functions and may be in a better form for use by power management systems. RelativeStateOfCharge() (0x0d); [0x0d] Description: Returns the predicted remaining battery capacity expressed as a percentage of FullChargeCapacity() (%). SMBus Protocol: Read Word Purpose: The RelativeStateOfCharge() function is used to estimate the amount of charge remaining in the battery relative to the last learned capacity. Output: Unsigned integer—remaining charge in mAh or 10mWh. SMBus Protocol: Read Word Output: Battery Mode CAPACITY_MODE CAPACITY_MODE bit = 0 bit = 1 Units mAh 10mWh Range 0–65,535mAh 0–65,535 10mWh Granularity mAh 10mWh Accuracy -0, +MaxError() ∗ FullChargeCapacity() Unsigned integer—percent of remaining capacity. Units: % Range: 0 to 100% Granularity: 1% Accuracy: -0, +MaxError() 22 bq2060 Accuracy: -0, +MaxError() ∗ FullChargeCapacity() / Current() FullChargeCapacity() (0x10); [0x10] Description: Returns the predicted pack capacity when it is fully charged. The FullChargeCapacity() value is expressed in either current (mAh at a C/5 discharge rate) or power (10mWh at a P/5 discharge rate) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. Invalid Data Indication: 65,535 indicates battery is not being discharged. AverageTimeToEmpty() (0x12); [0x12] Description: Returns a one-minute rolling average of the predicted remaining battery life (minutes). The AverageTimeToEmpty() value is calculated based on either current or power depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. Purpose: The FullChargeCapacity() function provides the user with a means of understanding the tank size of their battery. This information, along with information about the original capacity of the battery, can be presented to the user as an indication of battery wear. Purpose: The AverageTimeToEmpty() displays state-of-charge information in a more useful way. It averages the instantaneous estimations so the remaining time does not appear to jump around. SMBus Protocol: Read Word Output: SMBus Protocol: Read Word Unsigned integer—estimated full-charge capacity in mAh or 10mWh. Output: Unsigned integer — minutes of operation left. Battery Mode CAPACITY_MODE CAPACITY_MODE bit = 0 bit = 1 Units mAh 10mWh Range 0–65,535mAh 0–65,535 10mWh Granularity mAh 10mWh Accuracy -0, +MaxError() ∗ FullChargeCapacity() Units: minutes Range: 0 to 65,534 min Granularity: 2 min or better Accuracy: -0, +MaxError() ∗ FullChargeCapacity() / AverageCurrent() Invalid Data Indication: 65,535 indicates battery is not being discharged. RunTimeToEmpty() (0x11); [0x11] AverageTimeToFull() (0x13); [0x13] Description: Returns the predicted remaining battery life at the present rate of discharge (minutes). The RunTimeToEmpty() value is calculated based on either current or power depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. Description: Returns a one-minute rolling average of the predicted remaining time until the battery reaches full charge (minutes). Purpose: The AverageTimeToFull() function can be used by the SMBus Host’s power management system to aid in its policy. It may also be used to find out how long the system must be left on to achieve full charge. Purpose: The RunTimeToEmpty() provides the power management system with information about the relative gain or loss in remaining battery life in response to a change in power policy. This information is NOT the same as the AverageTimeToEmpty(), which is not suitable to determine the effects that result from a change in power policy. SMBus Protocol: Read Word Output: Unsigned integer —remaining time in minutes. SMBus Protocol: Read Word Units: minutes Output: Range: 0 to 65,534 minutes Unsigned integer—minutes of operation left. Granularity: 2 minutes or better Units: minutes Accuracy: MaxError() ∗ FullChargeCapacity() / AverageCurrent() Range: 0 to 65,534 min Invalid Data Indication: 65,535 indicates the battery is not being charged. Granularity: 2 min or better 23 bq2060 ChargingCurrent() (0x14); [0x14] Accuracy: not applicable Description: Returns the desired charging rate in mA. Invalid Data Indication: 65,535 indicates the charger should operate as a current source outside its maximum regulated voltage range. Purpose: The ChargingCurrent() function sets the ma x i mu m c har g e c ur r e nt o f the b a tt er y. T h e ChargingCurrent() value should be used in combination with the ChargingVoltage() value to set the charger’s operating point. Together, these functions permit the bq2060 to dynamically control the charging profile (current/voltage) of the battery. The bq2060 can effectively turn off a charger by returning a value of 0 for this function. The charger may be operated as a constant-voltage source above its maximum regulated current range by returning a ChargingCurrent() value of 65,535. BatteryStatus()(0x16); [0x16] Description: Returns the bq2060’s status word (flags). Some of the BatteryStatus() flags (REMAINING_CAPACITY_ALARM and REMAINING_TIME_ALARM) are calculated based on either current or power depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. This is important because use of the wrong calculation mode may result in an inaccurate alarm. SMBus Protocol: Read Word Output: Purpose: The BatteryStatus() function is used by the power-management system to get alarm and status bits, as well as error codes from the bq2060. This is basically the same information broadcast to both the SMBus Host and the Smart Battery Charger by the AlarmWarning() function except that the AlarmWarning() function sets the Error Code bits all high before sending the data. Unsigned integer—maximum charger output current in mA. Units: mA Range: 0 to 65,535mA Granularity: 1mA Accuracy: not applicable SMBus Protocol: Read Word Invalid Data Indication: 65,535 indicates that a charger should operate as a voltage source outside its maximum regulated current range. Output: Unsigned integer—Status Register with alarm conditions bit mapped as follows: ChargingVoltage() (0x15); [0x15] Description: Returns the desired charging voltage in mV. 0x8000 0x4000 0x2000 0x1000 0x0800 0x0400 0x0200 0x0100 Purpose: The ChargingVoltage() function sets the maxi mu m ch ar g e v o l ta g e o f t he b a tt er y. T h e ChargingVoltage() value should be used in combination with the ChargingCurrent() value to set the charger’s operating point. Together, these functions permit the bq2060 to dynamically control the charging profile (current/voltage) of the battery. The charger may be operated as a constant-current source above its maximum re g u l a t e d v o l t a g e r a ng e by r e t u r n in g a ChargingVoltage() value of 65,535. 0x0080 0x0040 0x0020 0x0010 SMBus Protocol: Write Word 0x0007 0x0006 0x0005 0x0004 0x0003 0x0002 0x0001 0x0000 Output: Unsigned integer—charger output voltage in mV. Units: mV Range: 0 to 65,535mV Granularity: 1mV 24 Alarm Bits OVER_CHARGED_ALARM TERMINATE_CHARGE_ALARM reserved OVER_TEMP_ALARM TERMINATE_DISCHARGE_ALARM reserved REMAINING_CAPACITY_ALARM REMAINING_TIME_ALARM Status Bits INITIALIZED DISCHARGING FULLY_CHARGED FULLY_DISCHARGED Error Codes Unknown Error BadSize Overflow/Underflow AccessDenied UnsupportedCommand ReservedCommand Busy OK bq2060 Alarm Bits FULLY_CHARGED bit is set when the bq2060 detects a primary charge termination or an overcharged condition. It is cleared when RelativeStateOfCharge() is less than or equal to the programmed Fully Charged Clear % in EE 0x4c. OVER_CHARGED_ALARM bit is set whenever the bq2060 detects that the battery is being charged beyond the Maximum Overcharge limit. This bit is cleared when the bq2060 detects that the battery is no longer being charged (i.e., the bq2060 detects discharge activity or no activity for the digital filter timeout periods. The digital filter timeout period (seconds) equates to 10 time the value shared in Digital Filter EE0x52.) FULLY_DISCHARGED bit is set when Voltage() is less than the EDV2 threshold. This bit is cleared when the Relative StateOfCharge() is greater than or equal to 20%. Error Codes Description The bq2060 processed the function OK code without detecting any errors. The bq2060 is unable to process the Busy function code at this time. The bq2060 detected an attempt to read or write to a function code reserved by this version of the Reserved specification. The 2060 detected an attempt to access an unsupported optional manufacturer function code. The bq2060 does not support this Unsupported function code which is defined in this version of the specification. The bq2060 detected an attempt to AccessDenied write to a read-only function code. The bq2060 detected a data overflow Over/Underflow or underflow. The bq2060 detected an attempt to BadSize write to a function code with an incorrect data block. The bq2060 detected an UnknownError unidentifiable error. TERMINATE_CHARGE_ALARM bit is set when the bq2060 detects that one or more of the battery’s charging parameters are out of range (e.g., its voltage, current, or temperature is too high) or when the bq2060 detects a primary charge termination. This bit is cleared when the parameter falls back into the allowable range, the termination condition ceases, or when the bq2060 detects that the battery is no longer being charged. OVER_TEMP_ALARM bit is set when the bq2060 detects that the internal battery temperature is greater than or equal to the MaxT limit. This bit is cleared when the internal temperature falls back into the acceptable range. TERMINATE_DISCHARGE_ALARM bit is set when the bq2060 detects that Voltage() is less than EDV0 or when the CVUV bit in Pack Status is set indicating that a Li-Ion cell voltage has dropped below the limit programmed in Cell Under / Over Voltage. The bit is cleared when Voltage() is greater than EDV0 or when the CVUV bit is cleared. REMAINING_CAPACITY_ALARM bit is set when the bq2060 detects that RemainingCapacity() is less than that set by the RemainingCapacityAlarm() function. This bit is cleared when either the value set by the RemainingCapacityAlarm() function is lower than the RemainingCapacity() or when the RemainingCapacity() is increased by charging. CycleCount()(0x17); [0x17] Description: Returns the number of cycles the battery has experienced. The mAh value of each count is determined by programming the Cycle Count Threshold value in EE 0x3c–0x3d. The bq2060 saves the cycle count value to Cycle Count EE 0x0e–0x0f after an update to CycleCount(). REMAINING_TIME_ALARM bit is set when the bq2060 detects that the estimated remaining time at the present discharge rate is less than that set by the RemainingTimeAlarm() function. This bit is cleared when either the value set by the RemainingTimeAlarm() function is lower than the AverageTimeToEmpty() or when the AverageTimeToEmpty() is increased by charging. Purpose: The CycleCount() function provides a means to determine the battery’s wear. It may be used to give advanced warning that the battery is nearing its end of life. Status Bits INITIALIZED bit is set when the bq2060 is has detected a valid load of EEPROM. It is cleared when the bq2060 detects an improper EEPROM load. SMBus Protocol: Read Word Output: Unsigned integer—count of total charge removed from the battery over its life. DISCHARGING bit is set when the bq2060 determines that the battery is not being charged. This bit is cleared when the bq2060 detects that the battery is being charged. Units: cycle Range: 0 to 65,534 cycles 65,535 indicates battery has experienced 65,535 or more cycles. 25 bq2060 Granularity: 1 cycle SpecificationInfo() (0x1a); [0x1a] Accuracy: absolute count Description: Returns the version number of the Smart Battery specification the battery pack supports, as well as voltage and current scaling information in a packed unsigned integer. Power scaling is the product of the voltage scaling times the current scaling. The SpecificationInfo is packed in the following fashion: (SpecID_H ∗ 0x10 + SpecID_L) + (VScale + IPScale∗ 0x10) ∗ 0x100. DesignCapacity() (0x18); [0x18] Description: Returns the theoretical or nominal capacity of a new pack. The DesignCapacity() value is expressed in either current (mAh at a C/5 discharge rate) or power, (10mWh at a P/5 discharge rate) depending on the setting of the BatteryMode()’s CAPACITY_MODE bit. The bq2060 VScale (voltage scaling) and IPScale (current scaling) should always be set to zero. The bq2060 sets SpecificationInfo() to the value programmed in Specification Information EE 0x14–0x15. Purpose: The DesignCapacity() function is used by the SMBus Host’s power management in conjunction with FullChargeCapacity() to determine battery wear. The power management system may present this information to the user and also adjust its power policy as a result. Purpose: The SpecificationInfo() function is used by the SMBus Host’s power management system to determine what information the Smart Battery can provide. SMBus Protocol: Read Word SMBus Protocol: Read Word Output: Output: Unsigned integer—battery capacity in mAh or 10mWh. Unsigned integer—packed specification number and scaling information. Battery Mode CAPACITY_MODE CAPACITY_MODE bit = 0 bit = 1 Units mAh 10mWh Range 0–65,535mAh 0–65,535 10mWh Granularity Not applicable Accuracy Not applicable Field Bits Used Format Allowable Values 4-bit binary 0–15 SpecID_L 0...3 value 4-bit binary 0–15 SpecID_H 4...7 value 4-bit binary 0 (multiplies voltage VScale 8...11 value by 10^ VScale) 4-bit binary 0 (multiplies current IPScale 12...15 value by 10 ^ IPScale) DesignVoltage() (0x19); [0x19] Description: Returns the theoretical voltage of a new pack (mV). The bq2060 sets DesignVoltage() to the value programmed in Design Voltage EE0x12–0x13. ManufactureDate() (0x1b); [0x1b] Description: This function returns the date the cell pack was manufactured in a packed integer. The date is packed in the following fashion: (year-1980) ∗ 512 + month ∗ 32 + day. The bq2060 sets ManufactureDate() to the value programmed in Manufacture Date EE 0x16–0x17. Purpose: The DesignVoltage() function can be used to give additional information about a particular Smart Battery’s expected terminal voltage. SMBus Protocol: Read Word Output: Units: mV Purpose: The ManufactureDate() provides the system with information that can be used to uniquely identify a particular battery pack when used in conjunction with SerialNumber(). Range: 0 to 65,535 mV SMBus Protocol: Read Word Granularity: not applicable Output: Unsigned integer—the battery’s designed terminal voltage in mV Accuracy: not applicable Unsigned integer—packed date of manufacture. 26 bq2060 Field Bits Used Day 0...4 Month 5...8 Year 9...15 Format 5-bit binary value 4-bit binary value 7-bit binary value Purpose: The DeviceName() function returns the battery’s name for identification purposes. Allowable Values 0–31 (corresponds to date) 1–12 (corresponds to month number) 0–127 (corresponds to year biased by 1980) SMBus Protocol: Read Block Output: String—character string with maximum length of 7 characters (7+length byte). DeviceChemistry() (0x22); [0x30-0x32] SerialNumber() (0x1c); [0x1c] Description: This function returns a character string that contains the battery’s chemistry. For example, if the DeviceChemistry() function returns NiMH, the battery pack would contain nickel metal hydride cells. The bq2060 sets DeviceChemistry() to the value programmed in Device Chemistry EE 0x40–0x44. Description: This function is used to return a serial number. This number, when combined with the ManufacturerName(), the DeviceName(), and the ManufactureDate(), uniquely identifies the battery (unsigned int). The bq2060 sets SerialNumber() to the value programmed in Serial Number EE 0x18–0x19. Purpose: The DeviceChemistry() function gives cell chemistry information for use by charging systems. The bq2060 does not use DeviceChemisty() values for internal charge control or fuel gauging. Purpose: The SerialNumber() function can be used to identify a particular battery. This may be important in systems that are powered by multiple batteries where the system can log information about each battery that it encounters. SMBus Protocol: Read Block Output: SMBus Protocol: Read Word String—character string with maximum length of 4 characters (4+length byte). Note: The following is a partial list of chemistries and their expected abbreviations. These abbreviations are NOT case sensitive. Output: Unsigned integer ManufacturerName() (0x20); [0x20-0x25] Description: This function returns a character array containing the battery’s manufacturer’s name. For example, MyBattCo would identify the Smart Battery’s ma n u fa ctur e r a s M y B at tC o . T he b q 2 0 6 0 s et s ManufacturerName() to the value programmed in Manufacturer Name EE 0x20–0x2a. Lead acid Lithium ion Nickel cadmium Nickel metal hydride Nickel zinc Rechargeable alkaline-manganese Zinc air Purpose: The ManufacturerName() function returns the name of the Smart Battery’s manufacturer. The manufacturer’s name can be displayed by the SMBus Host’s power management system display as both an identifier and as an advertisement for the manufacturer. The name is also useful as part of the information required to uniquely identify a battery. PbAc LION NiCd NiMH NiZn RAM ZnAr ManufacturerData() (0x23); [0x38–0x3a] Description: This function allows access to the manufacturer data contained in the battery (data). The bq2060 stores seven critical operating parameters in this data area. SMBus Protocol: Read Block Output: Purpose: The ManufacturerData() function may be used to access the manufacturer’s data area. The data fields of this command reflect the programming of five critical EEPROM locations and can be used to facilitate evaluation bq2060 under various programming sets. The ManufacturerData() function returns the following information in order: Control Mode, Digital Filter, Self-Discharge Rate, Battery Low %, Near Full, and the pending EDV threshold voltage (low byte and high byte.) String—character string with maximum length of 11 characters (11+length byte). DeviceName() (0x21); [0x28-0x2b] Description: This function returns a character string that contains the battery’s name. For example, a DeviceName() of BQ2060A would indicate that the batt e ry i s a m o d e l B Q 2060A . T he b q 2 0 6 0 s et s DeviceName() to the value programmed in Device Name EE 0x30–0x37. SMBus Protocol: Read Block 27 bq2060 Output: Block data—data that reflects EEPROM programming as assigned by the manufacturer with maximum length of 7 characters (7+length byte). OCE EDV2 b4 b3 b2 b1 EINT VDQ COK DOK CVOV 0 DFC pin is low 1 DFC pin is high CVOV The CVOV bit indicates that a secondary Li-Ion protection limit has been exceeded. It is set if any individual cell exceeds the programmed high voltage limit, if the pack voltage exceeds the overvoltage threshold, or if an over temperature condition occurs. The bit is not latched and merely reflects the present overvoltage status. The Pack Status Register consists of the following bits: b5 CFC pin is high The DOK bit indicates the status of the DFC pin of the bq2060. This function returns the Pack Status and Pack Configuration registers. The Pack Status register contains a number of status bits relating to bq2060 operation. The Pack Status register is the least significant byte of the word. The Pack Configuration register is the most significant byte of the word. The byte reflects how the bq2060 is configured as defined by the value programmed in Pack Configuration in EE 0x3f. b6 CFC pin is low 1 DOK Pack Status and Pack Configuration (0x2f); [0x2f] b7 0 b0 CVUV 0 No secondary protection limits exceeded 1 A secondary protection limit exceeded CVUV The CVUV bit indicates if any individual cell falls below the programmed low-voltage limit. The bit applies to lithium batteries only. The bit is not latched and merely reflects the present undervoltage status. OCE The OCE bit indicates that offset cancellation is enabled. The bq2060 sets this bit after VFC offset calibration is complete. 0 All series cells are above the low-voltage limit 0 Offset calibration is not enabled 1 A series cell is below the low voltage limit 1 Offset calibration is enabled VCELL4–VCELL1 (0x3c–0x3f); [0x3c–0x3f] EDV2 These functions return the calculated voltages in mV at the VCELL4 through VCELL1 inputs. The EDV2 bit indicates that Voltage() is less than the EDV2 threshold. 0 Voltage() > EDV2 threshold (discharging) EEPROM 1 Voltage() ≤ EDV2 threshold General EINT VDQ The bq2060 accesses the external EEPROM during a full reset and when storing historical data. During an EEPROM access, the VOUT pin becomes active and the bq2060 uses the ESCL and ESDA pins to communicate with the EEPROM. The EEPROM stores basic configuration information for use by the bq2060. The EEPROM must be programmed correctly for proper bq2060 operation. The VDQ bit indicates if the present discharge cycle is valid for an FCC update. Memory Map The EINT bit indicates that the VFC has detected a charge or discharge pulse. 0 No charge/discharge activity detected 1 Charge/discharge activity detected. 0 Discharge cycle is not valid 1 Discharge cycle is valid Table 10 shows the memory map for the EEPROM. It also contains example data for a 10 series NiMH and a 3s3p Li-Ion battery pack with a 0.05Ω sense resistor. COK The COK bit indicates the status of the CFC pin of the bq2060. 28 bq2060 Table 10. EEPROM Memory Map EEPROM Address 0x00 0x02 0x04 0x06 0x07 0x08 0x0a 0x0c 0x0e 0x10 0x12 0x14 0x16 0x18 0x1a 0x1c 0x1e 0x20 0x21 0x22 0x23 0x24 0x25 0x26 0x27 0x28 0x29 0x2a 0x2b 0x2c 0x2e 0x30 0x31 0x32 0x33 0x34 Name Check Byte 1 0x01 Remaining Time Alarm 0x03 0x05 Remaining Capacity Alarm EDV A0 Impedance Age Factor Reserved 0x09 Reserved Charging Voltage 0x0b 0x0d Reserved Cycle Count 0x0f 0x11 Reserved Design Voltage 0x13 Specification Information 0x15 Manufacture Date 0x17 Serial Number 0x19 Fast-Charging Current 0x1b Maintenance Charging 0x1d Current Pre-Charge Current 0x1f Manufacturer Name Length Character 1 Character 2 Character 3 Character 4 Character 5 Character 6 Character 7 Character 8 Character 9 Character 10 Light Discharge Current 0x2d Reserved Maximum Overcharge 0x2f Device Name Length Character 1 Character 2 Character 3 Character 4 Chemistry NiMH Example Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel 15487 10 minutes 350mAh Li-Ion, Nickel 0 Data MSB LSB 3c 7f 00 0a 01 5e Li-Ion Example 15487 10 minutes 400mAh Data MSB LSB 3c 7f 00 0a 01 90 - 00 0 - 00 0 0 Li-Ion, Nickel 18000mV 128 Li-Ion, Nickel 0 0 Li-Ion, Nickel 12000mV Li-Ion, Nickel v1.1/PEC Li-Ion, Nickel 2/25/99=9817 Li-Ion, Nickel 1 Li-Ion, Nickel 4000mA 00 46 00 00 00 2e 00 26 00 0f 00 00 50 80 00 00 e0 31 59 01 a0 0 0 12600mV 128 0 0 10800mV v1.1/PEC 2/25/99=9817 1 3000mA 00 31 00 00 00 2a 00 26 00 0b 00 00 38 80 00 00 30 31 59 01 b8 Li-Ion, Nickel 200mA 00 c8 0mA 00 00 Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel 800mA 9 B E N C H M A R Q 0 0 0 200mAh 7 B Q 2 0 03 00 ff - 20 09 42 45 4e 43 48 4d 41 52 51 00 00 00 38 07 42 51 32 30 100mA 9 B E N C H M A R Q 0 0 0 256mAh 7 B Q 2 0 00 00 ff - 64 09 42 45 4e 43 48 4d 41 52 51 00 00 00 00 07 42 51 32 30 (Continued on next page) Note: Reserved locations must be set as shown. Locations marked with an * are calibration values that can be adjusted for maximum accuracy. For these locations the table shows the appropriate default or initial setting. 29 bq2060 Table 10. EEPROM Memory Map (Continued) EEPROM Address 0x35 0x36 0x37 0x38 0x3a 0x3c 0x3e 0x3f 0x40 0x41 0x42 0x43 0x44 0x45 0x46 0x48 0x49 0x39 0x3b 0x3d 0x47 0x4a 0x4b 0x4c 0x4d 0x4e 0x4f 0x50 0x51 0x52 0x53 0x54 0x55 0x56 0x57 0x58 0x59 0x5a 0x5b Name Chemistry NiMH Example Character 5 Character 6 Character 7 Last Measured Discharge Pack Capacity Cycle Count Threshold Reserved Pack Configuration Device Chemistry Length Character 1 Character 2 Character 3 Character 4 MaxT DeltaT Overload Current Overvoltage Margin Overcurrent Margin Reserved Cell Under/Over Voltage Fast Charge Termination % Fully Charged Clear % Charge Efficiency Current Taper Threshold DeltaT Time Holdoff Time Current Taper Qual Voltage Manufacturers Data Length Control Mode Digital Filter Self-Discharge Rate Battery Low % Near Full Reserved Reserved Reserved Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Nickel Li-Ion Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion Nickel Nickel Li-Ion Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel - 6 0 A 4000mAh 4000mAh 500mAh 0 232 4 N I M H 50C, 3.0 6000mA 0 512mA 0 96% 90% 97% 180s 240s 7 4 50µV 1% 7% 200mAh 0 0 0 Data MSB LSB 36 30 41 0f a0 0f a0 fe 0c 00 e8 04 4e 49 4d 48 c7 17 70 00 20 00 a0 a6 el 07 04 07 04 2d cb 12 64 00 00 00 Li-Ion Example 6 0 A 4050mAh 4050mAh 3240mAh 0 246 4 L I O N 50C, 4.6 6000mA 800mV 512mA 118 100% 95% 100% 200mA 128mV 7 4 50µV 0.21% 7% 200mAh 0 0 0 Data MSB LSB 36 30 41 0f d2 0f d2 f3 58 00 f6 04 4c 49 4f 4e cf 17 70 32 20 76 9c a1 ff 12 40 07 04 2d 05 12 64 00 00 00 (Continued on next page) Note: Reserved locations must be set as shown. Locations marked with an * are calibration values that can be adjusted for maximum accuracy. For these locations the table shows the appropriate default or initial setting. 30 bq2060 Table 10. EEPROM Memory Map (Continued) EEPROM Address 0x5c 0x5e 0x60 0x61 0x62 0x5d 0x5f Description Chemistry NiMH Example Data MSB LSB 00 00 00 00 00 00 00 - Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion 0 0 0 0 0 - Nickel 0.25% - 20 - - - Li-Ion - - - 0 - 00 Nickel 96% - a0 - - - Li-Ion Nickel Li-Ion, Nickel Li-Ion, Nickel 1% 16 : 1 50 20 d4 0 16 : 1 4e 30 00 20 d4 20 d6 d6 d4 28 2d 11 00 ca 02 40 19 1e 7b 00 eb 14 00 a5 e6 fa 5a 0x66 0x68 0x67 0x69 Reserved VFC Offset* VFC Offset* Temperature Offset* ADC Offset* Cell 2 Calibration Factor* Efficiency Temperature Compensation Cell 3 Calibration Factor* Efficiency Drop Off Percentage Cell 4 Calibration Factor* Efficiency Reduction Rate ADC Voltage Gain* ADC Sense Resistor Gain* 0.05Ω 4e 30 0x6a 0x6c 0x6e 0x70 0x72 0x74 0x76 0x6b 0x6d 0x6f 0x71 0x73 0x75 0x77 VFC Sense Resistor Gain* VOC 25% VOC 50% VOC 75% EDVF/EDV0 EMF/ EDV1 EDV T0 Factor Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel 0.05Ω 11500mV 12500mV 13500mV 9500mV 10000mV 0 20 d3 cf cb 25 27 00 00 14 2c 44 1c 10 00 0x78 0x79 EDV C1/C0 Factor/EDV2 Li-Ion, Nickel 10500mV 29 04 0x7a 0x7c 0x7e 0x7b 0x7d 0x7f EDV R0 Factor EDV R1 Factor Check Byte 2 Li-Ion, Nickel Li-Ion, Nickel Li-Ion, Nickel 0 0 42330 00 a5 00 00 5a 0x63 0x64 0x65 Note: Li-Ion Example 0 0 0 0 0 0 0.05Ω 0.05Ω 10550mV 10750mV 11200mV 10265mV 11550 4475 C1 = 0 C0 = 235 5350 250 42330 Data MSB LSB 00 00 00 00 00 00 00 00 Reserved locations must be set as shown. Locations marked with an * are calibration values that can be adjusted for maximum accuracy. For these locations the table shows the appropriate default or initial setting. 31 bq2060 EEPROM Programming learning cycle. The bq2060 uses the Last Measured Discharge value to calculate FullChargeCapacity() in mAh or 10mWh mode. The following sections describes the function of each EEPROM location and how the data is to be stored. EDV Thresholds and Near Full Percentage Fundamental Parameters The bq2060 uses three pack voltage thresholds to provide voltage-based warnings of low battery capacity. The bq2060 uses the values stored in EEPROM for the EDV0, EDV1, and EDV2 values or calculates the three thresholds from a base value and the temperature, capacity, and rate adjustment factors stored in EEPROM. If EDV compensation is disabled then EDV0, EDV1, and EDV2 are stored directly in mV in EE 0x72–0x73, EE 0x74–0x75, and EE 0x78–0x79, respectively. Sense Resistor Value Two factors are used to scale the current related measurements. The 16-bit ADC Sense Resistor Gain value in EE 0x68–0x69 scales Current() to mA. Adjusting ADC Sense Resistor Gain from its nominal value provides a method to calibrate the current readings for system errors and the sense resistor value (RS) . The nominal value is set by 625 ADC Sense Resistor Gain= (Rs) For capacity correction at EDV2, Battery Low % EE 0 x 5 4 c a n b e s et a t a d es ir ed s t a t e- of - c h a r g e , STATEOFCHARGE%, in the range of 5 to 20%. Typical values for STATEOFCHARGE% are 7–12% representing 7 –12% capacity. (4) The 16-bit VFC Sense Resistor Gain in EE 0x6a–0x6b scales each VFC interrupt to mAh. VFC Sense Resistor Gain is based on the resistance of the series sense resistor. The following formula computes a nominal or starting value for VFC Sense Resistor Gain from the sense resistor value. VFC Sense Resistor Gain= 409.6 (Rs) Battery Low % = STATEOFCHARGE% ∗ 2.56 The bq2060 updates FCC if a qualified discharge occurs from a near-full threshold to EDV2. The desired near-full threshold window, NFW (mAh), is programmed in Near Full in EE 0x55. (5) Near Full = Sense resistor values are limited to the range of 0.00916 to 0.100Ω. (8) If EDV compensation is enabled, the bq2060 calculates battery voltage to determine EDV0, EDV1, and EDV2 thresholds as a function of battery capacity, temperature, and discharge load. The general equation for EDV0, EDV1, and EDV2 calculation is The digital filter threshold, VDF (µV), is set by the value stored in Digital Filter EE 0x52. 2250 VDF NFW 2 EDV Discharge Rate and Temperature Compensation Digital Filter Digital Filter = (7) (6) (9) Cell Characteristics EDV0,1,2 = EMF ∗ FBL - |ILOAD| ∗ R0 ∗ FTZ ∗ FCY where Battery Pack Capacity and Voltage n Pack capacity in mAh units is stored in Pack Capacity EE 0x3a–0x3b. In mAh mode, the bq2060 copies Pack Capacity to DesignCapacity(). In mWh mode, the bq2060 multiplies Pack Capacity by Design Voltage EE 0x12–0x13 to calculate DesignCapacity() scaled to 10mWh. Design Voltage is stored in mV. n EMF is a no-load battery voltage that is higher than the highest EDV threshold that is computed. EMF is programmed in mV in EMF/EDV1 EE 0x74–0x75. ILOAD is the current discharge load. FBL is the factor that adjusts the EDV voltage for battery capacity and temperature to match the no-load characteristics of the battery. The initial value for Last Measured Discharge in mAh is stored in EE 0x38–0x39. Last Measured Discharge is modified over the course of pack usage to reflect cell aging under the particular use conditions. The bq2060 updates Last Measured Discharge in mAh after a capacity FBL = f ( C0, C + C1, T ) where 32 (10) bq2060 n C (0%, 3%, or Battery Low % for EDV0, EDV1, and EDV2, respectively) and C0 are the capacity related EDV adjustment factors. C0 is programmed in the lower 11 bits of EDV C0 Factor/EDV2 EE 0x78–79. The Residual Capacity Factor is stored in the upper 5 bits of EE 0x78–0x79. FCY is the factor that adjusts for changing cell impedance as the battery pack is cycled. where FCY = f(A0, CycleCount()) n Residual Capacity Factor C1 =RESIDUAL% * 2.56 RESIDUAL % is the desired battery capacity remaining at EDV0 (RM = 0). n EMF = 11550 R0 ∗ FTZ represents the resistance of the battery as a function of temperature and capacity. n n C0 = 235 (11) C1 = 0 R0 = 5350 R1 = 250 T is the current temperature; C is the battery capacity relating to EDV0, EDV1, and EDV2; and C1 is the desired residual battery capacity remaining at EDV0 (RM = 0). A0 = 0 The graphs in Figures 7 and 8 show the calculated EDV0, EDV1, and EDV2 thresholds versus capacity using the typical compensation values for different temperatures and loads for a Li-Ion 3s3p 18650 pack. The compensation values vary widely for different cell types and manufacturers and must be matched exactly to the unique characteristics for optimal performance. R1 adjusts the variation of impedance with battery capacity. R1 is programmed in EDV R1 Rate Factor EE 0x7c–0x7d. T0 adjusts the variation of impedance with battery temperature. T0 is programmed in EDV T0 Rate Factor EE 0x76–0x77. Overload Current Threshold The Overload Current threshold is a 16-bit value stored in EE 0x46-0x47 in mA units. Battery Low % =7%, Temperature = 35 C Battery Low %= 7%, Load = 500mA 11500 11500 11000 11000 EDV2 10500 EDV2 10500 EDV1 EDV1 Voltage (mV) n T0 = 4475 R0 is the first order rate dependency factor stored in EDV R0 Factor EE 0x7a–0x7b. Voltage (mV) n A0 is the EDV aging factor that is stored in EDV A0 Factor EE 0x06. It should be set to 0 for most applications. Typical values for the EDV compensation factors for a Li-Ion 3s3p 18650 pack are T is the current temperature in °K FTZ = f ( R1 , T0, T, C + C1) (12) 10000 9500 9000 8500 10000 9500 9000 45C/500mA 8500 20C/500mA 8000 8000 35C/500mA 35C/1A 35C/2A 7500 EDV0 7500 7000 10 9 8 7 6 5 4 3 2 1 0 10 % Capacity 9 8 7 6 5 4 3 2 1 0 % Capacity Figure 8. EDV Calculations vs. Capacity for Various Loads Figure 7. EDV Calculations vs. Capacity for Various Temperatures 33 bq2060 Midrange Capacity Corrections Efficiency Reduction Rate = Three voltage-based thresholds, VOC25 EE 0x6c–0x6d, VOC50 EE 0x6e–0x6f, and VOC75 EE 0x70–0x71, are u se d t o t es t t he ac c ur a c y o f t he R M b a s ed on open-circuit pack voltages. These thresholds are stored in the EEPROM in 2’s complement of voltage in mV. The values represent the open-circuit battery voltage at which the battery capacity should correspond to the associated state of charge for each threshold. Self-Discharge Rate The nominal self-discharge rate, %PERDAY (% per day), is programmed in an 8-bit value Self-Discharge Rate EE 0x53 by the following relation: ERR% 0.0125 where 0 ≤ ERR% ≤ 3.19 The Efficiency Drop Off Percentage is stored in 2’s complement of percent. The bq2060 also adjusts the efficiency factors for temperature. TEFF% defines the percent efficiency reduction per degree C over 25°C. TEFF% is encoded in Efficiency Temperature Compensation EE 0x63 according to the following equation (17) Efficiency Temperature Compensation = æ 52.73 ö ÷ Self - Discharge Rate = 256 -ç è %PERDAY ø (13) TEFF% *1.6 0.0125 where 0 ≤ TEFF% ≤1.99 Light Load Current The amount of light load current in mA, ILEAK, used for compensation is stored in Light Discharge Current in EE 0x2b as follows: Light Discharge Current = (16) ILEAK * 1024 45 The bq2060 applies all four charge-compensation factors when the CHEM bit in Pack Configuration is not set denoting a nickel pack. (18) (14) Effective Charge Efficiency Reduction (nickel only) = ERR%[RSOC() – EFF%] + TEFF%[T(°C) – 25] ILEAK is between 0.044 and 11.2mA. where Charge Efficiency The bq2060 uses four charge-efficiency factors to compensate for charge acceptance. These factors are coded in Charge Efficiency, Efficiency Reduction Rate, Efficiency Drop Off Percentage, and Efficiency Temperature Compensation. The bq2060 applies the efficiency factor, EFF%, when RelativeStateOfCharge() is less than the value coded in Efficiency Drop Off Percentage EE 0x64. When RelativeStateOfCharge() is greater than or equal to the value coded in Efficiency Drop Off Percentage, EFF% and ERR% determine the charge efficiency rate. ERR% defines the percent efficiency reduction per percentage point of RelativeStateOfCharge() over Efficiency Drop Off Percentage. EFF% is encoded in High Charge Efficiency EE 0x4d according to the following equation: Charge Efficiency = 10 ∗ (EFF% - 74.5) (15) RSOC() ≥ EFF% and T ≥ 25°C If CHEM is set denoting a Li-Ion pack, the bq2060 applies only the value coded in High Charge Efficiency and makes no other adjustments for charge acceptance. Charge Limits and Termination Techniques Charging Voltage The 16-bit value, Charging Voltage EE 0x0a-0x0b programs the ChargingVoltage() value broadcast to a Smart Charger. It is also sets the base value for determining overvoltage conditions during charging and voltage compliance during a constant-voltage charging methodology. It is stored in mV. Overvoltage where 74.5 ≤ EFF% ≤ 100 ERR% is encoded in Efficiency Reduction Rate EE 0x65 according to the following equation: The 8-bit value, Overvoltage Margin EE 0x48, sets the limit over ChargingVoltage() that is to be considered as an overvoltage charge-suspension condition. The voltage in mV above the ChargingVoltage(), VOVM, that should 34 bq2060 trigger a charge suspend is encoded in Overvoltage Margin as follows: Overvoltage Margin= VOVM 16 FULLY_CHARGED Bit Clear Threshold (19) The bq2060 clears the FULLY_CHARGED bit in BatteryStatus() when RelativeStateOfCharge() reaches the value, Fully Charged Clear % EE 0x4c. Fully Charged Clear % is an 8-bit value and is stored as a 2’s complement of percent. VOVM is between 0 and 4080mV. Charging Current Fast Charge Termination Percentage ChargingCurrent() values are either broadcast to a Level 2 Smart Battery Charger or read from the bq2060 by a Level 3 Smart Battery Charger. The bq2060 sets the value of ChargingCurrent(), depending on the charge requirements and charge conditions of the pack. The bq2060 sets RM to a percentage of FCC on charge termination if the CSYNC bit is set in the Pack Configuration register. The percentage of FCC is stored in Fast Charge Termination % in EE 0x4b. The value is stored in 2’s complement of percent. Wh e n fa s t c ha r g e i s a l l o w e d , the bq 2 0 6 0 s et s ChargingCurrent() to the rate programmed in Fast Charging Current EE 0x1a-0x1b. Cycle Count Threshold Cycle Count Threshold 0x3c–0x3d sets the number of mAh that must be removed from the battery to increment CycleCount(). Cycle Count Threshold is a 16-bit value stored in 2’s complement of charge in mAh. Wh e n fa s t c har g e te r m i nat e s , t he b q 2 0 6 0 s et s ChargingCurrent() to zero and then to the Maintenance Charging Current EE 0x1c-0x1d when the termination condition ceases. ∆T/Dt Rate Programming When Voltage() is less than EDV0, the bq2060 sets ChargingCurrent() to Pre-charge Current EE 0x1e-0x1f. Typically this rate is larger than the maintenance rate to charge a deeply depleted pack up to the point where it may be fast charged. The ∆T portion of the ∆T/∆t rate is programmed in DeltaT, the low nibble of MaxT DeltaT EE 0x45 (least significant nibble). The ∆t portion is programmed in DeltaT Time EE 0x4e. ∆T/∆t = Fast Charging Current, Maintenance Charging Current, and Pre-Charge Current are stored in mA. DeltaT 0 1 2 3 4 5 6 7 8 9 a b c d e f Charge Suspension During charge, the bq2060 compares the current to the ChargingCurrent() plus the value IOIM. If the pack is charged at a current above the ChargingCurrent() plus IOIM, the bq2060 sets ChargingCurrent() set to zero to stop charging. IOIM is programmed in the EEPROM value, Overcurrent Margin, encoded as Overcurrent Margin= IOIM 16 (20) Overcurrent Margin EE 0x49 may be used to program IOIM values of 0 to 4080mA in 16mA steps. The desired temperature threshold for charge suspension, MAXTEMP, may be programmed between 45°C and 69°C in 1.6°C steps. MaxT DeltaT EE 0x45 (most significant nibble) is stored in a 4-bit value as shown: é 69 - MAXTEMP ù MaxT =ê ú ë û 1.6 (21) [DeltaT * 2 + 16] / 10 é ° Cù ë sú û [320 - DeltaT Time* 20]ê D(°C) 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 DeltaT_Time 00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f (22) t (s) 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 DT/Dt Hold-off Timer Programming The bq2060 suspends fast charge when fast charge continues past full by the amount programmed in Maximum Overcharge EE 0x2e-0x2f. Maximum Overcharge is programmed in 2s complement form of charge in mAh. The hold-off timer is programmed in the lower nibble of Holdoff Time EE 0x4f. The hold-off time is 320s minus 20 times the Holdoff Time value. 35 bq2060 Hold-off Time 00 01 02 03 04 05 06 07 Hold-off Time (s) 320 300 280 260 240 220 200 180 Hold-off Time 08 09 0a 0b 0c 0d 0e 0f Hold-off Time (s) 160 140 120 100 80 60 40 20 1 CSYNC In usual operation of the bq2060, the CSYNC bit is set so that the coulomb counter is adjusted when a fast charge termination is detected. In some applications, especially those where an externally controlled charger is used, it may be desirable NOT to adjust the coulomb counter. In these cases the CSYNC bit should be cleared. Current Taper Termination Characteristics Two factors in the EEPROM set the current taper termination for Li-Ion battery packs. The two coded locations are Current Taper Qual Voltage EE 0x4f and Current Taper Threshold EE 0x4e. Current taper termination occurs during charging when the pack voltage is above the charging voltage minus CELLV (mV) and the charging current is below the threshold coded in Current Taper Threshold for at least 40s. Current Taper Qual Voltage = Current Taper Threshold = CELLV 2 (23) RS* i 0.5625 (24) SMBus read access is limited to commands (0x05–0x1c) and (0x20–0x23). SMBus read/write access is limited to commands (0x00–0x04), (0x2f), and (0x3c–0x3f). 0 The bq2060 does not alter RM at the time of a valid charge termination. 1 The bq2060 updates RM with a programmed percentage of FCC at a valid charge termination. CEDV The CEDV bit determines whether the bq2060 implements automatic EDV compensation to calculate the EDV0, EDV1 and EDV2 thresholds base on rate, temperature, and capacity. If reset, the bq2060 uses the fixed values programmed in EEPROM for EDV0, EDV1 and EDV2. If set the bq2060 calculates EDV0, EDV1 and EDV2. where i = the desired current termination threshold in mA, and RS = VFC sense resistor in ohms. 0 EDV compensation disabled 1 EDV compensation enabled Pack Options VCOR Pack Configuration The VCOR bit enables the midrange voltage correction algorithm. When set, the bq2060 compares the pack voltage to RM and may adjust RM according to the values programmed in VOC25, VOC50, and VOC75. Pack Configuration EE 0x3f contains bit-programmable features. b7 b6 DMODE SEAL b5 b4 b3 b2 b1 b0 CSYNC CEDV VCOR CHEM LCC1 LCC0 0 Midrange corrections disabled 1 Midrange corrections enabled CHEM DMODE The CHEM bit configures the bq2060 for nickel packs (NiCd or NiMH) or Li-Ion packs. When set the bq2060 employs the configuration parameters in EEPROM designated for Li-Ion. When not set, the bq2060 employs the configuration parameters designated for nickel. The DMODE bit determines whether the LED outputs will indicate AbsoluteStateOfCharge() or RelativeStateOfCharge() 0 LEDs reflect AbsoluteStateOfCharge() 1 LEDs reflect RelativeStateOfCharge() SEAL The bq2060 uses nickel configuration parameters. 1 The bq2060 uses Li-Ion configuration parameters. LCC0 and LCC1 The SEAL bit determines the SMBus access state of the bq2060 on reset 0 0 The LCC0 and LCC1 bits configure the cell voltage inputs (VCELL1–4). SMBus commands (0x00–0xff) are accessible for both read and write. 36 bq2060 No. of Series Cells NA 2 3 4 Cell Voltage LCC1 LCC0 Inputs 00 VCELL4 = Cell Stack VCELL1 = Cell 1 01 VCELL2 = Cell 2 VCELL1 = Cell 1 10 VCELL2 = Cell 2 VCELL3 = Cell 3 VCELL1 = Cell 1 VCELL2 = Cell 2 11 VCELL3 = Cell 3 VCELL4 = Cell 4 a b c d e f 2688 2752 2816 2880 2944 3008 a b c d e f 4416 4448 4480 4512 4544 4576 Cycle Count Initialization Cycle Count EE 0x0e–0x0f stores the initial value for the CycleCount() function. It should be programmed to 0x0000. For Li-Ion packs with individual measurements, LCC0 and LCC1 define the number of series elements and their voltage measurement inputs. In each case (2, 3, or 4), the bq2060 uses the highest numbered cell voltage input to measure the pack voltage measurement as returned with Voltage(). For nickel chemistries or Li-Ion without single-cell measurements, LCC0 and LCC1 must be set to 00. VCELL4 is the pack voltage input for this programming. Control Modes Control Mode EE0x51 contains additional bit programmable features. b7 NDF b6 - b5 HPE b4 CPE b3 LED b2 SC b1 - b0 SM Remaining Time and Capacity Alarms NDF Remaining Time Alarm in EE 0x02–0x03 and Remaining Capacity Alarm in 0x04–0x05set the alarm thresholds used in the SMBus command codes 0x01 and 0x02, respectively. Remaining Time Alarm is stored in minutes and Remaining Capacity Alarm in mAh. The NDF bit disables the digital filter during discharge if the SMBC and SMBD lines are high. Secondary Protection Limits for Li-Ion HPE The cell undervoltage (VUV) and overvoltage (VOV) limits are programmed in Cell Undervoltage/Over Voltage EE 0x4a according to the equations: The HPE bit enables/disables PEC transmissions to the Smart Battery host for master mode alarm messages. Cell Undervoltage/Overvoltage (lower) = VOV - 4096 32 (25) Cell Undervoltage/Overvoltage (upper) = VUV - 2048 64 (26) Cell Under/Over Voltage (upper nibble) 0 1 2 3 4 5 6 7 8 9 VUV (mV) 2048 2112 2176 2240 2304 2368 2432 2496 2560 2624 Cell Under/Over Voltage (lower nibble) 0 1 2 3 4 5 6 7 8 9 0 Digital filter enabled all the time 1 Digital filter disabled if SMBC and SMBD are high 0 No PEC byte on alarm warning to host 1 PEC byte on alarm warning to host CPE The CPE bit enables/disables PEC transmissions to the Smart Battery Charger for master mode alarm messages. VOV (mV) 4096 4128 4160 4192 4224 4256 4288 4320 4352 4384 0 No PEC byte on broadcasts to charger 1 PEC byte on broadcasts to charger LED The LED bit configures the bq2060 for 4 or 5 LED indication 37 0 Selects the 5 LED indication mode 1 Selects the 4 LED indication mode bq2060 SC (27) The SC bit enables learning cycle optimization for a Smart Charger or independent charge 0 Learning cycle optimized for independent charger 1 Learning cycle optimized for Smart Charger é VCELL1*32768 ù é ADC Voltage Gain ù Vn1=ê + ADC Offsetú*ê ú û ë ûë 65536 1250 (28) é VCELL2*32768 ù Vn2=ê + ADC Offsetú* ë û 1250 SM é ADC Voltage Gain + 8* (Cell 2 CalibrationFactor) ù ê ú ë û 65536 The SM bit enables/disables master mode broadcasts by the bq2060 0 Broadcasts to host and charger enabled 1 Broadcasts to host and charger disabled (29) é VCELL3*32768 ù Vn3=ê + ADC Offsetú * ë û 1250 I f t h e S M bi t i s s e t , m o d i f i c a ti o ns t o b it s in BatteryMode() will not re-enable broadcasts. [ ADC Voltage Gain + 8* (Cell 3 CalibrationFactor) ]* é 2 ù ê ë 65536ú û Measurement Calibration (30) ADC é VCELL4*32768 ù Vn4=ê + ADC Offsetú* ë û 1250 To describe how the bq2060 calculates reported battery and individual cell voltages, the following abbreviations and designations are used: [ ADC Voltage Gain + 8* (Cell 4 CalibrationFactor)]* VCELL 1–4 = voltages at the input pins of the bq2060 é 2 ù ê ë 65536ú û VCELL1–4 = reported cell voltages Note: With LCC1-LCC0 = 00, Cell 4 Calibration Factor = 0. Vnl–4 = voltages at the different series nodes in the battery ADC Offset adjusts the ADC reading for voltage and current measurements. ADC Offset is a signed 8-bit value that cancels offset present in the circuit with no potential or current flow. ADC Offset is typically set between -20 and 20. Voltage() = reported battery voltage Vsr = voltage across the sense resistor The reported voltages measurements, Voltage() and VCELL1–4, may be calibrated by adjusting five 8- or 16-bit registers in EEPROM: ADC Offset in EE0x62, ADC Voltage Gain in EE 0x66–0x67, Cell 2 Calibration Factor in EE 0x63, Cell 3 Calibration Factor in EE 0x64, and Cell 4 Calibration Factor in EE 0x65. The bq2060 uses the computed node voltages to calculate the reported voltages. It does not compute reported cell voltages greater than the selected number of nodes. If no individual cell voltages are to be measured, LCC1–LCC0 should be set to 00 and the top of the battery stack should be connected to a voltage divider to the VCELL4 input. The bq2060 first computes the node voltages Vnl, Vn2, Vn3, and Vn4. The node voltages are inputs to the voltage dividers to the VCELL1 through VCELL4 input pins of the bq2060. The bq2060 computes node voltages to calculate the five reported voltages by the bq2060: Voltage(), VCELL1, VCELL2, VCELL3, and VCELL4. The bq2060 computes the reported voltages as follows: Voltage() = Vn4 (LCC1–LCC0 = 11 or 00) - Vsr Voltage() = Vn3 (LCC1–LCC0 = 10) - Vsr An ADC Voltage Gain factor of 20,000 is the nominal value when using the recommended cell-voltage division ratios of 16:1 on the VCELL4 and VCELL3 inputs and 8:1 on the VCELL2 and VCELL1 inputs. The bq2060 subtracts the voltage across the sense resistor from the measurements so that the reported voltages reflect the cell-stack voltages only. Voltage() = Vn2 (LCC1–LCC0 = 01) - Vsr VCELL4 = Vn4 - Vn3 VCELL3 = Vn3 - Vn2 VCELL2 = Vn2 - Vn1 The bq2060 compute the node voltages as 38 bq2060 VCELL1 = Vn1 - Vsr Constants and String Data Current EEPROM Constants The bq2060 scales Current() to mA units by the 16-bit value ADC Sense Resistor Gain in EE 0x68–0x69. Adjusting ADC Sense Resistor Gain from its nominal value provides a method to calibrate the current readings for variances in the ADC gain, internal voltage reference, and sense resistor value. The bq2060 calculates Current() by Check/Byte 1 EE 0x00–0x01 and Check Byte 2 EE 0x7e–0x7f must be programmed to 0x3c7f and 0xa55a, respectively. Specification Information Specification Information EE 0x14–0x15 stores the default value for the SpecificationInfo() function. It is stored in EEPROM in the same format as the data returned by the SepcificationInfo(). (31) Current() = [(ADC Reading + ADC Offset)* ADC Sense Resistor Gain] Manufacture Date 16,384 Manufacture Date EE 0x16–0x17 stores the default value for the ManufactureDate() function. It is stored in EEPROM in the same format as the data returned by the ManufactureDate(). The nominal value for ADC Sense Resistor Gain is given by equation (6). Serial Number Serial Number EE 0x18–0x19 stores the default value for the SerialNumber() function. It is stored in EEPROM in the same format as the data returned by the SerialNumber(). VFC To calibrate the coulomb counting measurement for VFC gain errors and sense resistor tolerance, the value of VFC Sense Resistor Gain EE 0x6a-0x6b may be adjusted from its nominal value. Manufacturer Name Data The nominal value of VFC Sense Resistor Gain is given by equation (5). Manufacturer Name Length EE 0x20 stores the length of t h e d es ir ed s t r in g t h a t is r et u r n ed b y t h e ManufacturerName() function. Locations EE 0x21–0x2a store the characters for ManufacturerName() in ASCII code. The bq2060 VFC circuit can introduce a signal opposite in sign from that of the inherent device and circuit offset to cancel this error. The offset calibration routine is initiated with commands to ManufacturerAccess(). Device Name Data The bq2060 calculates the offset with the calibration routine and stores the calibration value using the least 21 bits of VFC Offset in EE 0x5e–0x60. Device Name Length EE 0x30 stores the length of the desired string that is returned by the DeviceName() function. Locations EE 0x31–0x37 store the characters for DeviceName() in ASCII code. The least 20 bits store the offset calibration value (OCV). The sign of the offset calibration value is positive if the 21st bit is 0. OCV = 0.6V VFCuOffset19 – 0 Device Chemistry Data (32) Device Chemistry Length EE 0x40 stores the length of t h e d es ir ed s t r in g t h a t is r et u r n ed b y t h e DeviceChemistry() function. Locations EE 0x41–0x44 store the characters for DeviceChemistry() in ASCII code. Temperature The bq2060 uses Temperature Offset in EE 0x61 to calibrate the Temperature() function for offset. The required offset adjustment, TOFF (C), sets Temperature Offset according to the equation Temperature Offset = TOFF * 10 Manufacturers Data Length Manufacturers Data Length EE 0x50 stores the length of the desired number of bytes that is returned by the ManufacturersData() function. It should be set to 7. (33) where -12.8 ≤ TOFF ≤12.7 39 bq2060 Absolute Maximum Ratings Symbol Parameter Minimum Maximum Unit VCC—Supply voltage Relative to VSS -0.3 +6.0 V VIN–All other pins Relative to VSS -0.3 +6.0 V TOPR Operating temperature -20 +70 °C Notes Commercial Note: Permanent device damage may occur if Absolute Maximum Ratings are exceeded. Functional operation should be limited to the Recommended DC Operating Conditions detailed in this data sheet. Exposure to DC Electrical Characteristics (VCC = 2.7–3.7V, TOPR = -20–70°C, Unless Otherwise Noted) Symbol Parameter Conditions Minimum Typical VCC Supply voltage ICC Operating current VOUT inactive ISLP Low-power storage mode current 1.5V < VCC < 3.7V ILVOUT VOUT leakage current VOUT inactive -0.2 IVOUT VOUT source current VOUT active, VOUT = VCC - 0.6V -5.0 VOLS Output voltage low: LED1–LED5, CFC, DFC IOLS = 5mA Output voltage low: THON, CVON IOLS = 5mA 2.7 Maximum Unit 3.3 3.7 V 180 235 µA 10 µA 0.2 µA 5 mA 0.4 V 0.36 V Input voltage low DISP -0.3 0.8 V VIH Input voltage high DISP 2.0 VCC + 0.3 V VOL Output voltage low SMBC, SMBD, HDQ16, ESCL, ESDA 0.4 V VILS Input voltage low SMBC, SMBD, HDQ16, ESCL, ESDA -0.3 0.8 V VIHS Input voltage high SMBC, SMBD, HDQ16, ESCL, ESDA 1.7 6.0 V VAI Input voltage range VCELL1–4, TS, SRC VSS - 0.3 1.25 V IRB RBI data-retention input current 50 nA VRBI RBI data-retention voltage VIL IOL = 1.0mA VRBI > 3.0V, VCC < 2.0V 10 1.3 V ZAI1 Input impedance: SR1, SR2 0–1.25V 10 MΩ ZAI2 Input impedance: VCELL1–4, TS, SRC 0–1.25V 5 MΩ 40 bq2060 VFC Characteristics (VCC = 3.1–3.6V, TOPR = 0–70°C Unless Otherwise Noted)) Symbol Parameter Conditions VSR Input voltage range, VSR2 and VSR1 Minimum Typical Maximum VSR = VSR2 – VSR1 –0.25 VSROS VSR input offset VSR2 = VSR1, autocorrection disabled –250 VSRCOS Calibrated offset RMVCO Supply voltage gain coefficient (see Note) RMTCO Temperature gain coefficient (see note) –50 –16 VCC = 3.3V 0.8 Unit +0.25 V 250 µV +16 µV 1.2 %/V %/°C Slope for TOPR = –20 to 70°C –0.09 +0.09 Total Deviation TOPR = –20 to 70°C –1.6 0.1 % Slope for TOPR = –0 to 50°C –0.05 +0.05 %/°C Total Deviation TOPR = –0 to 50°C –0.6 0.1 % 0.21 % Maximum Unit 3.6 V Integral nonlinearity TOPR = 0–50C INL error Note: RMTCO total deviation is from the nominal gain at 25°C. REG Characteristics (TOPR = -20–70°C) Symbol Parameter VRO REG controlled output voltage IREG REG output current Conditions JFET: Rds(on) < 150Ω Vgs (off) < –3.0V @ 10µA Minimum Typical 3.1 1.0 41 3.3 µA SMBus AC Specifications (VCC = 2.7–3.7V, TOPR = -20–70°C, Unless Otherwise Noted) Symbol Parameter Conditions Min. FSMB SMBus operating frequency Slave mode, SMBC 50% duty cycle 10 SMBus master clock frequency Master mode, no clock low slave extend FMAS THD:STA TSU:STA TSU:STO Bus free time between start and stop Hold time after (repeated) start Repeated start setup time Stop setup time THD:DAT Data hold time TSU:DAT TTIMEOUT TLOW THIGH Data setup time Error signal/detect Clock low period Clock high period Cumulative clock low slave extend time Cumulative clock low master extend time TBUF TLOW:SEXT TLOW:MEXT Notes: 1. Typ. Max. Unit 100 kHz 51.2 kHz 4.7 µs 4.0 4.7 4.0 0 300 250 25 4.7 4.0 50 µs µs µs ns ns ns ms µs µs See Note 3 25 ms See Note 4 10 ms Receive mode Transmit mode See Note 1 See Note 2 35 The bq2060 will time out when any clock low exceeds TTIMEOUT. 2. THIGH Max. is minimum bus idle time. SMBC = SMBD = 1 for t > 50µs will cause reset of any transaction involving bq2060 that is in progress. 3. TLOW:SEXT is the cumulative time a slave device is allowed to extend the clock cycles in one message from initial start to the stop. The bq2060 typically extends the clock only 20µs as a slave in the read byte or write byte protocol. 4. TLOW:MEXT is the cumulative time a master device is allowed to extend the clock cycles in one message from initial start to the stop. The bq2060 typically extends the clock only 20µs as a master in the read byte or write byte protocol. HDQ16 AC Specifications (VCC = 2.7–3.7V, TOPR = -20–70 C, Unless Otherwise Noted) Symbol Parameter Min. Typ. Max. Unit tCYCH Cycle time, host to bq2060 (write) Conditions 190 - - µs tCYCB Cycle time, bq2060 to host (read) 190 205 250 µs tSTRH Start hold time, host to bq2060 (write) 5 - - ns tSTRB Start hold time, host to bq2060 (read) 32 - - µs tDSU Data setup time - - 50 µs tDSUB Data setup time - - 50 µs tDH Data hold time 100 - - µs tDV Data valid time 80 - - µs tSSU Stop setup time - - 145 µs tSSUB Stop setup time - - 145 µs tRSPS Response time, bq2060 to host 190 - 320 µs tB Break time 190 - - µs tBR Break recovery time 40 - - µs 42 bq2060 SMBus Timing Data HDQ16 Break Timing tBR tB TD201803.eps HDQ16 Host to bq2060 Write "1" Write "0" tSTRH tDSU tDH tSSU tCYCH HDQ16 bq2060 to Host Read "1" Read "0" tSTRB tDSUB tDV tSSUB tCYCB TD201805.eps 43 Ordering Information bq2060 -E411 Tape and Reel blank = tubes TR = tape and reel Package Option: SS = 28-pin SSOP (DBQ) Device: bq2060 SBS v1.1-Compliant Gas Gauge IC 44 Data Sheet Revision History Change No. Page No. Description Nature of Change 1 1 V-to-F Converter offset Was: 20µV Is: 16µV 2 1 Calibration of true battery capacity Was: from a programmable level of full to empty Is: from programmable near full to near empty levels 3 3 Digital filter operation Was: does not integrate charge or discharge counts Is: does not measure charge or discharge counts Was: flowing through the sense resistor because of offset. Is: flowing through the sense resistor 4 5 Figure 2. Bq2060 Operational Overview Add Light Discharge Compensation input. Delete Suspend Compensation box. Was: Is: FCC ( new) = DCR + (FCC * BatteryLow%) 5 6 Equation for value of FCC FCC(new) = DCR(final) = DCR(initial) + measured discharge to EDV2 +(FCC´ BatteryLow%) Battery Low% = (value stored in EE 0x54) ¸ 2.56 6 6 Battery voltage threshold for qualified discharge Was: voltage was greater than the EDV2 threshold Is: voltage was less than the EDV2 threshold 7 6 End-of-discharge thresholds Was: three compensated low-voltage thresholds Is: three low-voltage thresholds 8 7 Table 3 header Was: Access Is: SMBus Access Was: The bq2060 resumes EDV threshold detection after Current() drops below the overload current threshold. 9 8 EDV threshold reset 10 8 Self-discharge estimation rate Is: The bq2060 resumes EDV threshold detection after Current() drops below the overload current threshold. Any EDV threshold detected will be reset after 10mAh of charge are applied. Was: estimation for 25°C Is: estimation rate for 25°C Was: Self - Discharge Update Time = 640·13500 256· n´ (Y % per day) Is: Self - Discharge Update Time = 11 8 Replace times sign with mathematical bullet 640·13500 256· n · (Y % per day) Was: 640·13500 256· n´ (Y % per day) Is: 640·13500 256· n· (Y % per day) 45 = 6750 seconds = 6750 seconds seconds seconds Was: On detecting an overcurrent condition, the bq2060 sets the ChargingCurrent() to zero and sets the TERMINATE_CHARGE_ALARM bit in Battery Status(). The overcurrent condition and TERMINATE_ CHARGE_ALARM are cleared when the measured current drops below the ChargingCurrent plus the Overcurrent Margin. 12 10 Typos in overcurrent condition Is: On detecting an overcurrent condition, the bq2060 sets the ChargingCurrent() to zero and sets the TERMINATE_CHARGE_ALARM bit in Battery Status(). The overcurrent condition and TERMINATE_ CHARGE_ALARM are cleared when the measured current drops below the ChargingCurrent plus the Overcurrent Margin. 13 10 Typo in Overvoltage Was: BatteryStat-us() Is: BatteryStatus() 14 10 Overtemperature criterion Was: An over-temperature condition exists when Temperature() exceeds the Max T value programmed in EE 0x45 (most significant nibble). Is: An over-temperature condition exists when Temperature() is greater than or equal to the Max T value programmed in EE 0x45 (most significant nibble). 15 10 Overtemperature cleared Was: drops 5 degrees C below the Max T value or 43°C. Is: is equal to or below (Max T – 5°C) or 43°C. 16 11 Extensive changes in Table 6: Alarm and Status Bit Summary Was: See Table 6 in SLUS035C. Is: See Table 6 in SLUS035D. Fifth LED function Was: A 5th LED can be used with the 4 LED display option to show when the battery capacity is equal to 100%. Is: A 5th LED can be used with the 4 LED display option to show when the battery capacity is ≥ to 100%. Was: Detection of the transition activates the display and starts a display timer that advances for four seconds. Is: Detection of the transition activates the display and starts a four-second display timer. 17 12 18 12 Display activation 19 12 Display disabling Was: Unless noted, EDV0 = 0. Is: The display is disabled if EDV0 = 1. 20 15 SMBus On and Off State Was: OH State detection Is: Off State detection 21 15 Removal of tRR from Figure 6 Was: See Fig. 6 in SLUS035C. Is: See Fig. 6 in SLUS035D. 22 23 16 19 ManufacturerAccess description Time between settings of ALARM_MODE bit Was: This function provides writable command codes to control the bq2060 during normal operation and pack manufacture. Is: These commands can be ignored if sent within one second after a device reset. Was: An SMBus host that does not want the bq2060 to be a master on the SMBus must therefore continually set this bit at least once per 45s . . . . Is: To prevent the bq2060 from becoming a master on the SMBus, an SMBus host must therefore continually set this bit at least once per 50s . . . . 46 bq2060 Was: When cleared, the bq2060 transmits the ChargingCurrent() and ChargingVoltage() values to the Smart Battery Charger when charging is desired. Is: When cleared, the bq2060 transmits the ChargingCurrent() and ChargingVoltage() values to the Smart Battery Charger. 24 19 Enabling transmission of ChargingCurrent() and ChargingVoltage() 25 24 ChargingCurrent() Was: Range: 0 to 61,456mA Is: Range: 0 to 65,535mA 26 24 ChargingVoltage() Was: Range: 0 to 61,456mV Is: Range: 0 to 65,535mV Was: temperature is greater than allowed by the MaxT limit Setting OVER_TEMP_ALARM bit Is: temperature is greater than or equal to the MaxT limit 27 25 28 27 Setting ManufacturerName() Was: sets ManufacturerName() to the value programmed in Manufacturer Name EE 0x20–0x26 Is: sets ManufacturerName() to the value programmed in Manufacturer Name EE 0x20–0x2a 29 27 ManufacturerData() description Was: critical EEPROM programming parameters Is: critical operating parameters 30 27 ManufacturerData() purpose Was: calculated EDV threshold Is: pending EDV threshold voltage 31 28 Move paragraph from CVUV to Pack Status and Pack Configuration Was: Is: The Pack Configuration register reflects how the bq2060 is configured as defined by the value programmed in Pack Configuration in EE 0x3f. 32 28 Introduce Pack Status Register table Was: Is: The Pack Status Register consists of the following bits: 33 28 Pack Status EDV2 bit = 0 Was: Voltage() > EDV2 threshold Is: Voltage() > EDV2 threshold (discharging) 34 28 EINT bit function Was: The EDV2 bits indicate Is: The EDV2 bit indicates Setting the digital filter threshold, VDF (µV) Was: The desired digital filter threshold, VDF (µV), is set by calculating the value stored in Digital Filter EE 0x52. Is: The digital filter threshold, VDF (µV), is set by the value stored in Digital Filter EE 0x52. 35 32 36 32 Pack capacity storage Was: Pack capacity is programmed in mAh units to Pack Capacity in EE 0x3a–0x3b and Last Measured Discharge in EE 0x38–0x39. Is: Pack capacity in mAh units is stored in Pack Capacity EE 0x3a–0x3b. 37 32 Last Measured Discharge initial value storage Was: Is: The initial value for Last Measured Discharge in mAh is stored in EE 0x38–0x39. 47 bq2060 38 32 EDV compensation 39 33 FBL equation term definition 40 34 Self-discharge rate 41 35 Was: If EDV compensation is enabled, the bq2060 calculates battery voltage to determine EDV0, EDV1, EDV2 as a function of EDV, battery capacity, temperature, and discharge load Is: If EDV compensation is enabled, the bq2060 calculates battery voltage to determine EDV0, EDV1, and EDV2 thresholds as a function of battery capacity, temperature, and discharge load. Was: C is 0%, 3%, or Battery Low % for EDV0, EDV1, and EDV2, respectively and C0 is the capacity related EDV adjustment factors. Is: C (0%, 3%, or Battery Low % for EDV0, EDV1, and EDV2, respectively) and C0 are the capacity related EDV adjustment factors. æ 52.73 ö ÷ Was: Self - Discharge Rate = 2s ç è %PERDAY ø æ 52.73 ö ÷ Is: Self - Discharge Rate = 256 -ç è %PERDAY ø é 69 - MAXTEMP ù Was: MaxT = Intê + 0.5ú ë û 1.6 é 69 - MAXTEMP ù Is: MaxT =ê ú ë û 1.6 Temperature threshold equation Was: The bq2060 sets update RM with a programmed percentage of FCC. Is: The bq2060 updates RM with a programmed percentage of FCC at a valid charge termination. 42 36 CSYNC bit = 1 43 36 CEDV Was: If reset, the bq2060 uses the values . . . Is: If reset, the bq2060 uses the fixed values . . . 44 38 CPE bit = 0 Was: No PEC byte on alarm warning to charger Is: No PEC byte on broadcasts to charger 45 38 CPE bit = 1 Was: PEC byte on alarm warning to charger Is: PEC byte on broadcasts to charger 46 38 ADC Offset Was: adjusts the ADC offset Is: adjusts the ADC reading 47 38 ADC Offset Was: ADC Offset is typically set between -10 and 10. Is: ADC Offset is typically set between -20 and 20. 48 39 VFC Was: to calibrate the coulomb counting measurement for system errors and sense resistor error Is: to calibrate the coulomb counting measurement for VFC gain errors and sense resistor tolerance 49 39 VFC Was: opposite in sign as Is: opposite in sign to 50 40 Extensive changes in DC Electrical Characteristics table Was: SLUS035C version Is: SLUS035D version 51 40 VFC Characteristics table VSROS minimum/typical/maximum Was: -300/-50/250 Is: -250/-50/250 52 41 VFC Characteristics Was: VCC = 3.1–3.5V Is: VCC = 3.1–3.6V 48 53 41 REG Characteristics Was: VCC = 3.5V (max) Is: VCC = 3.6V (max) 54 41 VFC Characteristics table RMVCO conditions Was: VCC = 3.5V Is: VCC = 3.3V 55 41 VFC Characteristics table Note Was: Note: RMTCO total deviation is from the gain at 25°C. Is: Note: RMTCO total deviation is from the nominal gain at 25°C. 56 41 REG Characteristics table title Was: REG Characteristics Is: REG Characteristics (TOPR = -20–70°C) 57 42 SMBus AC Specifications table title Was: SMBus AC Specifications (TA = TOPR, 2.9V < VCC < 3.7V unless otherwise noted) Is: SMBus AC Specifications (VCC = 2.7–3.7V, TOPR = -20–70°C, Unless Otherwise Noted) 58 42 59 42 HDQ16 AC Specifications table tDH minimum Was: 90µs Is: 100µs 60 42 HDQ16 AC Specifications table tRSPS minimum Was: 320µs Is: 190µs 61 42 HDQ16 AC Specifications table tRSPS maximum Was: Is: 320ms 62 45 HDQ16 AC Specifications table title Was: HDQ16 AC Specifications (TA = TOPR, 2.9V < VCC < 3.7V unless otherwise noted) Is: HDQ16 AC Specifications (VCC = 2.7–3.7V, TOPR = -20–70°C, Unless Otherwise Noted) Replace package diagram and Ordering Information Package Option with SS = 28-pin SSOP (DBQ) Was: SLUS035C version Is: SLUS035D version 49 PACKAGE OPTION ADDENDUM www.ti.com 4-Mar-2005 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Eco Plan (2) Qty BQ2060SS-E207-EP ACTIVE SSOP/ QSOP DBQ 28 40 None CU NIPDAU Level-1-220C-UNLIM BQ2060SS-E207TR-EP ACTIVE SSOP/ QSOP DBQ 28 2500 None CU NIPDAU Level-1-220C-UNLIM BQ2060SS-E411 ACTIVE SSOP/ QSOP DBQ 28 40 None CU NIPDAU Level-1-220C-UNLIM BQ2060SS-E411TR ACTIVE SSOP/ QSOP DBQ 28 2500 None CU NIPDAU Level-1-220C-UNLIM Lead/Ball Finish MSL Peak Temp (3) (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - May not be currently available - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. None: Not yet available Lead (Pb-Free). Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Green (RoHS & no Sb/Br): TI defines "Green" to mean "Pb-Free" and in addition, uses package materials that do not contain halogens, including bromine (Br) or antimony (Sb) above 0.1% of total product weight. (3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDECindustry standard classifications, and peak solder temperature. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis. Addendum-Page 1 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and applications using TI components. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for such altered documentation. Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Following are URLs where you can obtain information on other Texas Instruments products and application solutions: Products Applications Amplifiers amplifier.ti.com Audio www.ti.com/audio Data Converters dataconverter.ti.com Automotive www.ti.com/automotive DSP dsp.ti.com Broadband www.ti.com/broadband Interface interface.ti.com Digital Control www.ti.com/digitalcontrol Logic logic.ti.com Military www.ti.com/military Power Mgmt power.ti.com Optical Networking www.ti.com/opticalnetwork Microcontrollers microcontroller.ti.com Security www.ti.com/security Telephony www.ti.com/telephony Video & Imaging www.ti.com/video Wireless www.ti.com/wireless Mailing Address: Texas Instruments Post Office Box 655303 Dallas, Texas 75265 Copyright 2005, Texas Instruments Incorporated