ATA6870N Li-Ion, NiMH Battery Measuring, Charge Balancing and Power-supply Circuit DATASHEET Features ● 12-bit battery-cell voltage measurement ● Simultaneous battery cells measurement in parallel ● Cell temperature measurement ● Charge Balancing Capability ● Parallel balancing of cells possible ● Integrated power supply for MCU ● Undervoltage detection ● Less than 10µA standby current ● Low cell imbalance current (< 10µA) ● Hot plug-in capable ● Interrupt timer for cycling MCU wake-ups ● Cost-efficient solution due to cost-optimized 30V CMOS technology ● Reliable communication between stacked ICs due to level shifters with current sources and checksum monitoring of data ● Daisy-chainable ● Each IC monitors up to 6 battery cells ● 16 ICs (96 cells) per string ● No limit on number of strings ● Package QFN48 7mm 7mm Applications ● Battery measurement, supply and monitoring IC for Li-ion and NiMH battery systems in Electric (EV) and Hybrid Electrical (HEV) Vehicles ● Electrical and hybrid electrical vehicles ● Li-Ion batteries as 12V lead-acid battery replacement ● Ebike, scooters ● Uninterruptible power supply (UPS) ● Smart grid Benefits ● Cost reduction due to integrated measurement circuit and high voltage power-supply 9317D-AUTO-07/15 1. Description The Atmel® ATA6870N is a measurement and monitoring circuit designed for Li-ion and NiMH multicell battery stacks in hybrid electrical vehicles. The Atmel ATA6870N monitors the battery-cell voltage and the battery-cell temperature with a 12-bit ADC. The circuit also provides charge-balancing capability for each battery-cell. In addition, a linear regulator is integrated to supply a microcontroller or other external components. Reliable communication between stacked ICs is achieved by level-shifters with current sources. The Atmel ATA6870N can be connected to three, four, five or six battery-cells. Up to 16 circuits (96 cells) can be cascaded in one string. The number of strings is not limited. 2. Block Diagram Figure 2-1. Block Diagram To ATA6870 above VDDHV MBAT7 PD_N DISCH6 Digital Level Shifter Cell 6: Reference ADC Cell Balancing Standby Control PD_N_OUT VDDHVP 3.3V Voltage Regulator MBAT6 POW_ENA VDDHVM AVDD 3.3V Internal Voltage Regulator DISCH1 Logic Cell 1: Reference ADC Cell Balancing Digital Level Shifter MBAT2 BIASRES Internal Biasing MBAT1 NTC NTC Interchip and Microcontroller Communication Interface Test Cell Temperature Measuring TEMP1 Digital Level Shifter TEMPREF TEMP2 TEMPVSS GND AVSS DVSS SCANMODE PWTST DTST CS_FUSE DVDD VDDFUSE MISO_IN MOSI_OUT SCK_OUT CS_N_OUT CLK_OUT IRQ_IN CS_N SCK MOSI MISO IRQ CLK MCU MFIRST ATST To ATA6870 below 2 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Pin Configuration Table 3-1. MBAT6 DISCH6 MBAT7 VDDHV IRQ_IN CLK_OUT CS_N_OUT SCK_OUT MOSI_OUT MISO_IN PD_N VDDHVP Figure 3-1. Pinning QFN48, 7 mm 7 mm 48 47 46 45 44 43 42 41 40 39 38 37 DISCH5 1 36 VDDHVM MBAT5 2 35 PD_N_OUT DISCH4 3 34 POW_ENA MBAT4 4 33 PWTST DISCH3 5 32 BIASRES MBAT3 6 31 TEMPREF DISCH2 7 30 TEMP2 MBAT2 8 29 TEMP1 DISCH1 9 28 TEMPVSS MBAT1 10 27 AVSS IRQ 11 26 AVDD CLK 12 25 ATST 15 16 17 18 19 20 21 22 23 24 MISO MFIRST DTST SCANMODE CS_FUSE VDDFUSE DVSS DVDD GND 14 MOSI 13 SCK Atmel ATA6870N CS_N 3. Pin Description Pad Number Pad Name Exposed Pad Function Remark Heatslug 1 DISCH5 Output to drive external cell-balancing transistor 2 MBAT5 Battery cell sensing line 3 DISCH4 Output to drive external cell-balancing transistor 4 MBAT4 Battery cell sensing line 5 DISCH3 Output to drive external cell-balancing transistor 6 MBAT3 Battery cell sensing line 7 DISCH2 Output to drive external cell-balancing transistor 8 MBAT2 Battery cell sensing line 9 DISCH1 Output to drive external cell-balancing transistor 10 MBAT1 Battery cell sensing line 11 IRQ Interrupt output for MCU/ATA6870N below 12 CLK System clock 13 CS_N 14 SCK SPI clock input from MCU/ATA6870N below 15 MOSI Master Out Slave In input from MCU Chip select input from MCU/ATA6870N below SPI data input ATA6870N [DATASHEET] 9317D–AUTO–07/15 3 Table 3-1. Pin Description (Continued) Pad Number 4 Pad Name Function Remark Master In Slave Out output for MCU SPI data output 16 MISO 17 MFIRST 18 DTST Test-mode pin Connected to AVSS 19 SCANMODE Test-mode pin Connected to AVSS 20 CS_FUSE Test-mode pin Connected to AVSS 21 VDDFUSE Test-mode pin Connected to AVSS 22 DVSS Digital negative supply 23 DVDD Digital positive supply input (3.3V) Select Master/Slave 24 GND Ground 25 ATST Test-mode pin 26 AVDD 3.3V Regulator output 27 AVSS Analog negative supply 28 TEMPVSS 29 TEMP1 Temperature measuring input 1 30 TEMP2 Temperature measuring input 2 31 TEMPREF Reference voltage for temperature measuring 32 BIASRES Internal supply current adjustment 33 PWTST 34 POW_ENA Power regulator enable/disable 35 PD_N_OUT Power down output 36 VDDHVM Power regulator output to supply e.g. an external microcontroller 37 VDDHVP Power regulator supply voltage 38 PD_N 39 MISO_IN Master In Slave Out input from ATA6870N above 40 MOSI_OUT Master Out Slave In output for ATA6870N above 41 SCK_OUT SPI clock output for input of ATA6870N above 42 CS_N_OUT 43 CLK_OUT 44 IRQ_IN Interrupt input from ATA6870N above 45 VDDHV Supply voltage 46 MBAT7 Battery cell sensing line 47 DISCH6 Output to drive external cell-balancing transistor 48 MBAT6 Battery cell sensing line ATA6870N [DATASHEET] 9317D–AUTO–07/15 Connected to AVDD Keep pin open Ground for temperature measuring Test - mode pin Power down input Chip select output for input of ATA6870N above System clock output for input of ATA6870N above Keep pin open 4. ATA6870N System Overview The Atmel® ATA6870N can be stacked up to 16 times in one string. The communication with MCU is carried out on the lowest level through an SPI bus. The data on the SPI bus is transmitted to the 15 other Atmel ATA6870Ns using the communication interface implemented inside Atmel ATA6870N. Figure 4-1. Battery Management Architecture with One Battery String Atmel ATA6870N Atmel ATA6870N Atmel ATA6870N Atmel ATA6870N MCU ATA6870N [DATASHEET] 9317D–AUTO–07/15 5 Figure 4-2. Battery Management Architecture with Several Battery Strings Atmel ATA6870N Atmel ATA6870N MCU OPTO Atmel ATA6870N Atmel ATA6870N MCU 6 ATA6870N [DATASHEET] 9317D–AUTO–07/15 To Battery Master Controller 5. Absolute Maximum Ratings Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Unless otherwise specified all voltages to pin AVSS. Parameters Symbol Min. Ambient temperature TA Junction temperature TJ Storage temperature Battery cell voltage Pin Max. Unit –40 +85 °C –40 +125 °C TS –55 +150 °C VMBAT(i+1) VMBAT(i) –0.3 +5.5 V VVDDHV - VVMBAT7 –5.5 +0.3 V MBAT1 VMBAT1 –0.3 +0.3 V VDDHVP VVDDHVP –0.3 +33.6 V MBAT(i+1), MBAT(i) VVDDHV - VVMBAT7max VMBAT1 Supply voltage power regulator Operating supply voltage VDDHV VVDDHV –0.3 +30 V Supply voltage DVDD (regulator is off) DVDD VDVDD –0.3 +5.5 V Supply voltage AVDD (regulator is off) AVDD VAVDD –0.3 +5.5 V Test-input VDDFUSE VVDDFUSE –0.3 +5.5 V Reference voltage for temperature measuring (regulator is Off) TEMPREF VTEMPREF –0.3 VDD+0.3 V Supply voltage VDDHVM (regulator is Off) VDDHVM V VDDHVM –0.3 +5.5 V DVSS VAVSS - VGND –0.3 +0.3 V Digital ground Analog ground AVSS VAVSS - VGND –0.3 +0.3 V AVSS, DVSS VAVSS - VDVSS –0.3 +0.3 V TEMPVSS VTEMPVSS –0.3 +0.3 V CLK, CS_N, SCK, MOSI, DTST, ATST, SCANMODE, MFIRST, POW_ENA, CS_FUSE, PWTST VCLK, VCS_N, VSCK, VMOSI, VDTST, VATST, VSCANMODE, VMFIRST, VPOW_ENA, VCS_FUSE, VPWTST –0.3 VDD + 0.3 V IRQ, MISO VIRQ, VMISO –0.3 +5.5 V Input voltage for analog I/O pins TEMP1, TEMP2, BIASRES VTEMP1, VTEMP2, VBIASRES –0.3 VDD + 0.3 V Input voltage for digital high voltage input pins MISO_IN, IRQ_IN VMISO_IN, VIRQ_IN VDDHV – 0.3 VDDHV + 0.3 V Voltage at digital high voltage output pins MOSI_OUT, SCK_OUT, CS_N_OUT, CLK_OUT VMOSI_OUT, VSCK_OUT, VCS_N_OUT, VCLK_OUT VDDHV – 0.3 VDDHV + 0.3 V PD_N V PD_N VDDHV – 5.5 VDDHV + 0.3 V PD_N_OUT V PD_N_OUT –5.5 +0.3 V DISCH(i) VDISCH(i) VMBAT(i) – 0.3 VMBAT(i+1) + 0.3 V Digital/analog ground Ground voltage for temperature measuring Input voltage for logic I/O pins Input: PD_N Output: PD_N_OUT Voltage at cell balancing outputs ATA6870N [DATASHEET] 9317D–AUTO–07/15 7 5. Absolute Maximum Ratings (Continued) Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Unless otherwise specified all voltages to pin AVSS. Parameters Pin Symbol Min. ESD ±2 kV ESD 500 V ESD 750 V LATCH-UP ±100 mA HBM ESD ANSI/ESD-STM5.1 JESD22-A114 AEC-Q100 (002) CDM ESD STM 5.3.1 1, 12, 13, 24, 25, 36, 37, 48 Latch-up acc. to AECQ100-004, JESD78A 6. Max. Unit Thermal Resistance Parameters Symbol Value Unit Rthja 25 K/W Package. QFN48 77 Max. thermal resistance junction-ambient(1) Max. thermal resistance junction-case RthjC TBD Note: 1. Package mounted on 4 large PCB (per JESD51-7) under natural convention as defined in JESD51-2. 7. K/W Circuit Description and Electrical Characteristics Unless otherwise specified all parameters in this section are valid for a supply voltage range of 6.9V < VDDHV < 30V and a battery cell voltage of VMBAT(i+1) – VMBAT(i) = 0V to 5V, –40°C < TA < 85°C. All values refer to pin AVSS, unless otherwise specified. 7.1 Operating Modes The Atmel® ATA6870N has two operation modes. 1. Power-down mode (PDmode) 2. 7.1.1 Normal mode (NORM mode) Power-down Mode In power-down mode all blocks of the IC are switched off. The circuit can be switched from Power-down to ON mode or back via the PD_N input. If the pin is connected to VDDHV via an external optocoupler, for example, the circuit is in ON mode. If several Atmel ATA6870N are stacked, the power-down signal must be only provided for the IC on the top level of the stack. The next lower IC receives this information from the PD_N_OUT output of its upper IC. The PD_N_OUT pin must be connected to either the PD_N pin of the next lower Atmel ATA6870N or to AVSS. 8 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Figure 7-1. Power-down VDDHV MBAT7 PD_N Digital Level Shifter Cell 6: Reference ADC Cell Balancing DISCH6 Standby Control PD_N_OUT VDDHVP 3.3V Voltage Regulator POW_ENA VDDHVM MBAT6 AVDD ATA6870 3.3V Internal Voltage Regulator Cell 1: Reference ADC Cell Balancing DISCH1 Internal Biasing MBAT1 NTC Interchip and Microcontroller Communication Interface Test Cell Temperature Measuring TEMP1 NTC Digital Level Shifter TEMPREF TEMP2 MISO_IN MOSI_OUT SCK_OUT CS_N_OUT CLK_OUT IRQ_IN CS_N SCK MOSI MISO IRQ CLK MFIRST ATST VDDFUSE DTST CS_FUSE PWTST SCANMODE DVSS AVSS TEMPVSS GND DVDD BIASRES Logic Digital Level Shifter MBAT2 VDDHV MBAT7 PD_N Digital Level Shifter Cell 6: Reference ADC Cell Balancing DISCH6 Standby Control PD_N_OUT VDDHVP 3.3V Voltage Regulator POW_ENA VDDHVM MBAT6 AVDD ATA6870 3.3V Internal Voltage Regulator Cell 1: Reference ADC Cell Balancing DISCH1 Logic Digital Level Shifter MBAT2 BIASRES Internal Biasing MBAT1 TEMPREF NTC MCU MFIRST VDDFUSE ATST DTST CS_FUSE PWTST SCANMODE DVSS AVSS TEMPVSS GND MISO_IN MOSI_OUT SCK_OUT CS_N_OUT CLK_OUT IRQ_IN CS_N SCK MOSI MISO IRQ CLK Test Cell Temperature Measuring TEMP1 NTC Interchip and Microcontroller Communication Interface Digital Level Shifter TEMP2 DVDD ATA6870N [DATASHEET] 9317D–AUTO–07/15 9 Table 7-1. Electrical Characteristics No. Parameters Test Conditions Pin Symbol 1.1 Maximum allowed input current in power-down mode (e.g., leakage current of an optocoupler) PD_N IPD_N 1.2 Input current in ON mode PD_N IPD_N 1.3 Maximum voltage (pin PD_N left open) Max. Unit Type* 50 µA A 5 mA A PD_N VVDDHV VPD_N 5 V A 1.4 Propagation delay time from power-down mode to NORM mode DVDD tVDDON 3 ms A 1.5 Propagation delay time from NORM mode to power-down mode DVDD tVDDOFF 10 ms A IPD_N = 0 to 50µA Min. Typ. 2.5 min slope 1 mA I PD_N = ------------msec *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter 7.1.2 Normal Operating Mode (NORM Mode) The Atmel® ATA6870N turns on when the PD_N signal is switched from low to high. The power supplies AVDD and DVDD as well as VDDHVM (if the input signal POW_ENA = high) are turned on. The configuration registers are set to their default values. In NORM mode the Atmel ATA6870N can acquire analog data (voltage or temperature channels) upon request from the host microcontroller. When the host microcontroller orders an acquisition through the SPI bus, the IC starts digitizing all voltage and one temperature channel in parallel. The on-chip digital signal processor filters, in real time, the channel samples. When conversion and filtering are done, the data-ready interrupt to the host processor indicates the data availability. The MCU can now read the ADC result registers. The MCU reads the Atmel ATA6870N’s status registers to check each IC and to acknowledge the interrupt. When Atmel ATA6870N is in NORM mode, the MCU can be active or in idle mode. In order to wake-up the MCU by an interrupt, the Low Frequency Timer (LFT) can be activated in Atmel ATA6870N. Interrupt is signaled with a high level on IRQ pin. The LFT is re-programmable on the fly and can be reset through SPI, but is not stoppable. Figure 7-2. Atmel ATA6870N in NORM Mode ASICs in NOMode Idle IRQ SPI MCU 10 ACQ Cmd Background Send SPI Background task Command task/Idle ATA6870N [DATASHEET] 9317D–AUTO–07/15 Acquisition Asserted Read status register Interrupt Handling Idle Read data burst mode Background task Processing Table 7-2. Electrical Characteristics No. Parameters Test Conditions Pin Symbol Min. 6.9 2.1 Supply voltage VDDHV VVDDHV 2.2 Current consumption IVDDHV (normal mode) VDDHV IVDDHV 2.3 Current consumption in power-down mode (PDmode) IVDDHV + IMBAT(i)max(1) VMBAT(i+1) – VMBAT(i) = 3.7V VDDHV 2.4 Imbalance from battery cell to battery cell in power-down mode (PDN Mode) VMBAT(i+1) – VMBAT(i) = 3.7V MBAT(i+1) Typ. IMBAT(i+1) Max. Unit Type* 30 V A 15 mA A 10 µA A 10 µA A *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Note: 7.2 1. Largest input current of the cell inputs MBAT(i) Interface to Battery Cells Each input line MBAT(i) and the supply lines VDDHV, AVSS can be protected by additional resistors and a filter capacitor as shown below. Figure 7-3. External Components between Atmel ATA6870N and the Battery Cells R_VDDHV R_IN VDDHV MBAT(i+1) Discharge Resistor Battery cell(i) Cell(i) DISCH(i) R_IN R_VSS Battery cell Board MBAT(i) AVSS ATA6870 MBAT(i) are high impedance input (~2M). Thus, external components can be added to protect ATA6870N chip against current spikes and overvoltage at battery cell level. ATA6870N [DATASHEET] 9317D–AUTO–07/15 11 Table 7-3. Electrical Characteristics No. Parameters 3.1 R_IN 3.2 R_VDDHV 3.3 R_VSS Test Conditions Pin Symbol Min. Typ. Max. Unit Type* MBAT(i) 1 k D VDDHV 50 D AVSS 50 D *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter 7.3 Reduced Number of Battery Cells Configuration It is possible for Atmel® ATA6870N to operate with a reduced number of cells: 3, 4, 5, and 6 cell operation are possible. In these cases, the cell-chip inputs corresponding to the missing cells should be connected to the upper cell potential of the module. VDDHV Figure 7-4. Connection with 4 Cells only MBAT7 PD_N PD_N_OUT DISCH6 VDDHVP POW_ENA MBAT6 VDDHVM DISCH5 AVDD DVDD MBAT5 BIASRES DISCH4 Atmel ATA6870N MBAT4 DISCH3 MISO_IN MOSI_OUT SCK_OUT MBAT3 CS_N_OUT CLK_OUT DISCH2 IRQ_IN MBAT2 CS_N DISCH1 SCK MFIRST VDDFUSE ATST DTST CS_FUSE SCANMODE PWTST MISO DVSS TEMPREF TEMP2 TEMP1 TEMPVSS AVSS MOSI GND MBAT1 IRQ CLK Battery cell 1 (MBAT1, MBAT2) and battery cell 6 (MBAT6, MBAT7) must always be used for the lowest/highest cell. 12 ATA6870N [DATASHEET] 9317D–AUTO–07/15 7.4 ATA6870N External MCU Supply The Atmel® ATA6870N provides a 3.3V power-supply for external components such as the microcontroller unit (MCU). The input pin for this supply is pin VDDHVP, and the output pin is VDDHVM. This regulator is able to supply the MCU directly from the topmost battery cell of a string. The power regulators of all stacked Atmel ATA6870N are therefore put in serial configuration to avoid imbalance.The regulator can be disabled with the digital input pin POW_ENA. Table 7-4. Truth Table Pin Symbol POW_ENA VPOW_ENA Value Function Low Voltage regulator disabled High Voltage regulator enabled Logic levels: Low = VDVSS, High = VDVDD ATA6870N [DATASHEET] 9317D–AUTO–07/15 13 Figure 7-5. MCU Supply with the Internal Power Supply VDDHV MBAT7 PD_N Digital Level Shifter Standby Control Cell 6: Reference ADC Cell Balancing DISCH6 PD_N_OUT VDDHVP 3.3V Voltage Regulator POW_ENA VDDHVM MBAT6 AVDD ATA6870 3.3V Internal Voltage Regulator Cell 1: Reference ADC Cell Balancing DISCH1 Logic Digital Level Shifter MBAT2 BIASRES Internal Biasing MBAT1 Cell Temperature Measuring TEMP1 Interchip and Microcontroller Communication Interface Test Digital Level Shifter TEMPREF TEMP2 MISO_IN MOSI_OUT SCK_OUT CS_N_OUT CLK_OUT IRQ_IN CS_N SCK MOSI MISO IRQ CLK MFIRST ATST VDDFUSE DTST CS_FUSE SCANMODE PWTST DVSS GND TEMPVSS AVSS DVDD + VDDHV MBAT7 PD_N Standby Control Digital Level Shifter Cell 6: Reference ADC Cell Balancing DISCH6 PD_N_OUT VDDHVP 3.3V Voltage Regulator POW_ENA VDDHVM MBAT6 AVDD ATA6870 3.3V Internal Voltage Regulator Cell 1: Reference ADC Cell Balancing DISCH2 Logic Digital Level Shifter MBAT2 BIASRES TEMPREF Interchip and Microcontroller Communication Interface Digital Level Shifter Test Cell Temperature Measuring TEMP1 9317D–AUTO–07/15 MFIRST VDDFUSE ATST DTST CS_FUSE SCANMODE PWTST DVSS GND ATA6870N [DATASHEET] AVSS TEMPVSS 14 + Internal Biasing MBAT1 TEMP2 DVDD MISO_IN MOSI_OUT SCK_OUT CS_N_OUT CLK_OUT IRQ_IN CS_N SCK MOSI MISO IRQ CLK MCU Table 7-5. Electrical Characteristics No. Parameters 4.1 Test Conditions Pin Symbol Min. Supply voltage VDDHVP VVDDHVP 6.9 4.2 Output voltage VDDHVM VVDDHVM 3.1 4.3 DC output current VDDHVM 4.4 Peak output current(1) VDDHVM Typ. Max. Unit Type* 33.3 V A 3.5 V A IVDDHVM 20 mA A IVDDHVM 50 mA A 3.3 Capacitor load (2) VDDHVM 30 33 µF D 4.6 Capacitor load (2) VDDHVM 200 220 nF D 4.7 High level input voltage POW_ENA VPOW_ENA V A 4.8 Low level input voltage POW_ENA VPOW_ENA V A 4.9 Hysteresis POW_ENA VPOW_ENA 0.05 VDVDD V C 4.10 Input current POW_ENA IPOW_ENA –1 µA A 4.5 VPOW_ENA = 0V to VDVDD 0.7 VDVDD 0.3 VDVDD +1 *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Notes: 1. Maximum current the power regulator can provide, time limited by thermal consideration only 2. These capacitors are mandatory ATA6870N [DATASHEET] 9317D–AUTO–07/15 15 Figure 7-6. MCU Supply with an External Power Supply VDDHV MBAT7 PD_N Digital Level Shifter Standby Control Cell 6: Reference ADC Cell Balancing DISCH6 PD_N_OUT VDDHVP 3.3V Voltage Regulator POW_ENA VDDHVM MBAT6 AVDD ATA6870 3.3V Internal Voltage Regulator Cell 1: Reference ADC Cell Balancing DISCH2 Logic Digital Level Shifter MBAT2 BIASRES Internal Biasing MBAT1 Cell Temperature Measuring TEMP1 Interchip and Microcontroller Communication Interface Test Digital Level Shifter TEMPREF TEMP2 MISO_IN MOSI_OUT SCK_OUT CS_N_OUT CLK_OUT IRQ_IN CS_N SCK MOSI MISO IRQ CLK MFIRST ATST VDDFUSE DTST CS_FUSE PWTST SCANMODE DVSS AVSS TEMPVSS GND DVDD VDDHV MBAT7 PD_N Standby Control Digital Level Shifter Cell 6: Reference ADC Cell Balancing DISCH6 PD_N_OUT VDDHVP 3.3V Voltage Regulator MBAT6 VDDHVM AVDD ATA6870 3.3V Internal Voltage Regulator Cell 1: Reference ADC Cell Balancing DISCH2 Logic Digital Level Shifter MBAT2 BIASRES Cell Temperature Measuring TEMP1 Interchip and Microcontroller Communication Interface Test Digital Level Shifter TEMPREF TEMP2 9317D–AUTO–07/15 MFIRST VDDFUSE ATST DTST CS_FUSE PWTST SCANMODE DVSS AVSS GND TEMPVSS ATA6870N [DATASHEET] DVDD Internal Biasing MBAT1 16 POW_ENA MISO_IN MOSI_OUT SCK_OUT CS_N_OUT CLK_OUT IRQ_IN CS_N SCK MOSI MISO IRQ CLK MCU 7.5 Analog Blocks 7.5.1 Battery Voltage Measuring Figure 7-7. Block Diagram Battery Voltage Measurement External ATA6870N 1.666V Reference DVDD MBAT(i+1) Cell i MBAT(i) 12 bits incremental ADC High voltage level shifter (digital) DISCH(i) Bitstream CLK MUX Disch(i) DVSS The battery voltage measurement block contains ● a 2-input multiplexer ● ● ● a voltage reference, a 12-bit ADC the upper part of digital voltage level shifters 7.5.1.1 Input Multiplexer The multiplexer has 3 inputs. Each of the functions are described in the table below: Table 7-6. Inputs of the Multiplexer Input Function V(MBAT(i+1), MBAT(i)) Input voltage measurement V(MBAT(i), MBAT(i)) Offset error acquisition of ADC The multiplexer inputs are controlled by SPI. ATA6870N [DATASHEET] 9317D–AUTO–07/15 17 7.5.1.2 12 Bits Incremental ADC The purpose of this cell is to convert an analog input into a 12-bit digital word. Table 7-7. Electrical Characteristics No. Parameters 5.1 Accuracy of voltage channel(1) Test Conditions Pin Symbol Min. Typ. Max. Unit Type* Maximum input noise 0.5mVrms 2.2V < VMBAT(i+1) – VMBAT(i) < 4.5V MBAT(i+1), MBAT(i) –10 +10 mV A Maximum input noise 0.5mVrms 0V < VMBAT(i+1) – VMBAT(i) < 5V MBAT(i+1), MBAT(i) –20 +20 mV A Maximum input noise 0.5mVrms VMBAT(i+1) – VMBAT(i) = 3.7V TJ = –20°C to +65°C MBAT(i+1), MBAT(i) –7 +7 mV A Maximum input noise 0.5mVrms Aging(3) MBAT(i+1), MBAT(i) –11 +11 mV C Maximum input noise 0.5mVrms Aging(4) MBAT(i+1), MBAT(i) –17 +17 mV C 0 5 V A MBAT(i+1), MBAT(i) 5.2 Input voltage range VMBAT(i+1), VMBAT(i) 5.3 Input resolution (1 LSB) VLSB 1.5 mV D 5.4 Reference voltage VRef 1.667 V D 5.5 Offset voltage MBAT(i+1), MBAT(i) VMBAT(i+1), VMBAT(i) 410 LSB A 5.6 Gain voltage MBAT(i+1), MBAT(i) VMBAT(i+1), VMBAT(i) 655 LSB/V A 5.7 System clock CLK fCLK kHz D 5.8 SPI interface clock 5.9 Conversion rate(2) SCK tconv = (212 + 1) / fCLK 5.10 Input bandwidth MBAT(i+1), MBAT(i) 450 500 550 0.5 fCLK fSCK D tconv 8.194 ms D fBW 50 Hz D *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Notes: 18 1. The accuracy of the voltage channels is guaranteed with no external resistor in the MBAT(i), MBAT(i+1) lines. 2. Conversion rate without readout times of SPI 3. Aging temperature TJ = 125°C, drift measured at 25°C and 85°C 4. Aging temperature TJ = 125°C, drift measured at –40°C ATA6870N [DATASHEET] 9317D–AUTO–07/15 Converting ADC Results to Voltage The silicon is factory adjusted by measuring offset voltage (VOffset) with both ADC inputs connected to MBATi and calibration of the adc(MBATi+1) value to 3031 at MBATi+1 = 4.0V (see Figure 7-8). Figure 7-8. Characteristics of AD-converter ADC output 3686D = 0.9D x 212 3031 Slope = (3031 - 410D)/4V = 655DLSB/V 410D = 0.1 x 212 Input Voltage (MBATi+1, MBATi) 0 0 4 5 adc(VOffset): ADC result with both ADC inputs connected to MBATi (0V input voltage) adc(VMBATi+1-VMBATi): Uncorrected ADC result of the ADC input voltage Standard Procedure with Frequent Offset Adjustment To use the frequent offset adjustment of the ADC the following parameters need to be measured: adc(VOffset) ADC result with both ADC inputs connected to MBATi (0V input voltage) adc(VMBATi+1-VMBATi) Uncorrected ADC result of the ADC input voltage Calculation of the battery cell voltage: VIn = 4V (adc(VMBATi+1-VMBATi) – adc(VOffset)) / (3031 – adc(VOffset)) with VIn = V(MBATi+1)-V(MBATi) It’s not necessary to measure VOffset during every measuring cycle. Regular updates are sufficient. Standard Procedure without Offset Adjustment With increasing input voltages the failure caused by the ADC can be ignored. In this case the battery cell voltage can be calculated by the following equation: VIn = 4V (adc(VMBATi+1-VMBATi) – 0.1212) / (3031 – 0.1212) The following simplification can be done with less than 1mV rounding error: VIn = 1.52656 10-3 (adc(VMBATi+1-VMBATi) – 410) ATA6870N [DATASHEET] 9317D–AUTO–07/15 19 7.5.1.3 Acquisition Time and Clocking The acquisition time depends on the number of Atmel® ATA6870Ns to be addressed. Table 7-8. Electrical Characteristics Number of ATA6870N SCK Frequency (kHz) CLK Frequency (kHz) Conversion Time (ms) Total Acquisition Duration (ms)(1) 1 250 500 8.2 9.5 2 250 500 8.2 10.2 3 250 500 8.2 10.8 4 250 500 8.2 11.5 5 250 500 8.2 12.2 6 125 500 8.2 17.0 7 125 500 8.2 18.4 8 125 500 8.2 19.7 9 125 500 8.2 21.1 10 62.5 500 8.2 36.1 11 62.5 500 8.2 38.8 12 62.5 500 8.2 41.5 13 62.5 500 8.2 44.2 14 62.5 500 8.2 46.8 15 62.5 500 8.2 49.5 Note: 16 62.5 500 8.2 52.2 1. The total acquisition time takes the following into account: - ADC conversion - Reading of voltage values in burst mode for all ATA6870N devices, - Reading of temperature values for all ATA6870N devices (only one temperature input is read). SPI clock (pin SCK) must a maximum of half the frequency of the system clock CLK. 20 ATA6870N [DATASHEET] 9317D–AUTO–07/15 7.5.2 Battery Cell Discharge Each battery cell can be discharged with an external resistor and an NMOS transistor. Figure 7-9. External Circuit for Cell Balancing R_VDDHV VDDHV R_IN MBAT(i+1) Discharge Resistor Battery cell(i) Cell(i) DISCH(i) R_IN MBAT(i) R_VSS Battery cell AVSS Board ATA6870 The pin DISCH(i) (Discharge for battery cell i) is intended to switch on the external discharge resistor in parallel to the battery cell to bypass charge current for cell balancing reasons. The pin DISCH(i) is a digital output: No discharge: VDISCH(i) = VMBAT(i) Discharge: VDISCH(i) = VMBAT(i+1) Table 7-9. Electrical Characteristics No. Parameters Test Conditions 6.1 Operating voltage range Pin Symbol Min. MBAT(i) MBAT(i+1) – MBAT(i) 1.5 Typ. Max. Unit Type* 5 V A 6.2 High-level output voltage IDISCH(i) = –10µA, MBAT(i+1) – MBAT(i) = 1.5V to 5V DISCH(i) VDISCH(i) – VMBAT(i) VMBAT(i+1) – 50 mV V A 6.3 High-level output voltage IDISCH(i) = –1mA MBAT(i+1) – MBAT(i) = 3V to 5V DISCH(i) VDISCH(i) – VMBAT(i) VMBAT(i+1) – 0.6V V A k A 6.4 Pull-down resistor(1) DISCH(i)MBAT(i) 60 140 *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Note: 1. Integrated pull-down resistor between pins DISCH(i) and MBAT(i) ATA6870N [DATASHEET] 9317D–AUTO–07/15 21 7.5.3 Temperature Channel The temperature sensors are based on a resistor divider using a standard resistor and an NTC resistor. This resistor divider is connected to the reference of the ADC for temperature measuring. As the ADC is sharing same reference value, the output of temperature measurement with ADC is ratio metric. Figure 7-10. Battery Cell Temperature Measurement AVDD TEMPREF RES_REF2 1.2V Reference RES_REF1 TEMP1 TEMP2 RES_NTC2 12 bits Incremental ADC OUT RES_NTC1 Operation Register TEMPVSS During one measuring cycle only one temperature input can be measured by the ADC. The channel can be selected in the Operation Register (0x02) by the TempMode bit (bit 3). The ADC output is equal to: RES_NTC(1) 8 8 out = 2048 1 + --------------------------------------------------------------------------- ------ – ------ (RES_NTC(1) + RES_REF(1)) 15 10 Table 7-10. Electrical Characteristics No. Parameters Test Conditions Pin Symbol Min. Typ. Max. Unit Type* 1.1 1.2 1.3 V A 2 mA A VTEMPR V A V A µA A 7.1 Reference voltage TEMPREF VTEMPREF – VTEMPVSS 7.2 Reference voltage output current TEMPREF ITEMPREF 7.3 Input voltage range TEMP1 VTEMP1 0 VTEMP2 0 7.4 Input voltage range TEMP2 TEMPx EF VTEMPR EF 7.5 Input current VTEMPx = 1.2V ITEMPx 1 7.6 Code output for value(RES_NTCx) = value (RES_REFx) V(TEMPi, TEMPVSS) = 0.5 V(TEMPREF, TEMPVSS) 931D 956D 981D A 7.7 Code output for value(RES_NTC) = 0 V(TEMPi, TEMPVSS) = 0 385D 410D 435D A 7.8 Code output for value(RES_NTC) = infinite V(TEMPi, TEMPVSS) = V(TEMPREF) 1477D 1502D 1527D A *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter 22 ATA6870N [DATASHEET] 9317D–AUTO–07/15 7.5.4 Internal Voltage Regulator The regulator output is pin AVDD. The pins AVDD and DVDD have to be connected together. An external filtering capacitor (10nF recommended) is used to filter and stabilize the function. The regulator output can be used to supply outside functions at the price of power supply imbalance between battery cells. Table 7-11. Electrical Characteristics No. Parameters Pin Symbol Min. VDDHV VVDDHV 6.9 Regulated output voltage AVDD VAVDD 3.1 8.3 Output current AVDD IAVDD 0 8.4 Cload (load capacitor) 8.1 Supply voltage range 8.2 Test Conditions Cload 9 Typ. 3.3 Max. Unit Type* 30 V A 3.5 V A 5 mA A nF D 10 *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter 7.5.5 Central Biasing This block generates a precise bias current to supply internal blocks of the IC. Connection of any external loads to this pin is not allowed. Table 7-12. Electrical Characteristics No. Parameters 9.1 Biasing voltage 9.2 External resistor 9.3 Tolerance 9.4 Maximum external parasitic capacitor Test Conditions Pin Symbol BIASRES VBIASRES RRefbias RRefbias BIASRES Min. Typ. Max. Unit Type* 1.2 V A 121 k D +1 % D 50 pF D –1 CExternal *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Figure 7-11. Internal Bias Current Generation IBIAS Bandgap 1.2V BIASRES RREFBIAS 121kΩ ATA6870N [DATASHEET] 9317D–AUTO–07/15 23 7.5.6 RC Oscillator Table 7-13. Internal RC Oscillator Frequency No. Parameters Test Conditions Pin Symbol Min. Typ. Max. Unit Type* fOsc 45 50 55 kHz A 10.1 Oscillator frequency *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter 7.5.7 Power On Reset The power on reset is used to initialize the digital part at power-up. The power on reset circuit is functional when the voltage at pin DVDD is larger than VPOROP. There are two reset sources: System “hard reset” System hard reset occurs when the voltage at pin DVVD goes below the power on reset threshold. ATA6870N registers are set to their initial values. After t = tRESET, the MCU can access the Atmel® ATA6870N. Figure 7-12. Power On Reset VPOROFF VPORON VPOROP VDVDD VPOR Table 7-14. Electrical Characteristics No. Parameters Test Conditions Pin Symbol Min. 11.1 Power on reset functional DVDD VPOROP 11.2 Power on reset off DVDD VPOROFF 1.5 11.3 Power on reset hysteresis DVDD VPOROFF – VPORON 0.03 11.4 Power on reset time tRESET Typ. Max. Unit Type* 0.8 V A 2.5 V A V C µs A 800 *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter 24 ATA6870N [DATASHEET] 9317D–AUTO–07/15 7.6 Digital Part 7.6.1 General Features The digital parts of the ATA6870N includes the following blocks: ● 4-wire-SPI full duplex communication with external host MCU ● ● ● ● 7.6.2 SPI system protocol management (frames decoding) and configuration registers bank Interrupt to MCU management Operations decoding (voltage and/or temperature acquisition) and analog part control Low frequency timer (50kHz) for wake-up management Host Interface Figure 7-13. Host Interface VDDMicrocontroller Unit CS_N VDVDD SCK SPI Master SPI MOSI MFIRST MISO MCU IRQ SPI Slave ATA6870N (1) The communication between Atmel® ATA6870N (1) and its host MCU, as well as ATA6870N (n) and ATA6870N(n-1) is based on a 4 wire serial/parallel SPI interface (CS_N, SCK, MISO, MOSI) and an interrupt line (IRQ). The SPI interface allows register read and write operations. The interrupt line indicates events that require host intervention. Atmel ATA6870N(n)’s 4 wire-SPI bus inputs (CS_N, SCK, MOSI) are up-shifted through level shifters. They are internally connected to the outputs CS_N_OUT, SCK_OUT, MOSI_OUT and connected to ATA6870N(n+1) (CS_N, SCK, MOSI). Atmel ATA6870N(n)’s 4 wire-SPI bus output (MISO) and ATA6870N(n)’s interrupt (IRQ) are down-shifted through level shifters and connected to ATA6870N(n-1) (MOSI_IN, IRQ_IN) or host MCU (n = 1). ATA6870N [DATASHEET] 9317D–AUTO–07/15 25 7.6.3 Interrupt In NORM mode (normal mode), the reasons for an interrupt request are: ● The availability of measured data (data ready) When a voltage measurement is completed, the dataRdy flag is set in the status register. The ATA6870N cannot decode any new incoming operation until the dataRdy flag is released. ● The low frequency timer (LFT) elapses (wakeup) The wakeup flag is set in the status register when the LFT elapses. The LFT is controlled via the SPI interface. ● ● A transmission error is flagged during the last SPI transaction (the commError bit is set in the status register). If an undervoltage condition occurs. The undervoltage function is controllable via SPI interface. A mask bit in the irqMask register corresponds to each interrupt source. The MCU must read the ATA6870N status register before the interrupt is cleared. With each SPI access a 16-bit IRQ state is sent via MISO to the MCU with the interrupt state of all stacked ATA6870N (see Section 7.6.4.1 “SPI Transaction Fields” on page 26). In PDmode (power down), if the digital control part and MCU are not supplied, neither SPI command nor interrupt are transmitted over the interface. 7.6.4 SPI Interface The full duplex SPI interface block allows communication with the host MCU using four wires (MISO, MOSI, SCK and CS_N). SPI transactions are based on a byte-access MSB first protocol. 7.6.4.1 SPI Transaction Fields Most of the time, the SPI frame is defined by 4 distinct fields: IDENTIFICATION (2 bytes): 16-bit chip identification (MOSI), in parallel 16-bit IRQ state (MISO) CONTROL (1 byte): 7-bit register address + 1-bit read/write information (MOSI) DATA (k byte): k*8 bits data (MOSI or MISO depending on the access direction) CHKSUM (1 byte): 8 bits if the Chksum_ena bit is set in the Ctrl register (register 0x01, bit 4) Figure 7-14. SPI Transaction Fields Organization byte1 byte2 byte3 byte4 byte5 to n-1 MOSI ChipID1 ChipID0 CONTROL DATA .... MISO IRQID1 IRQID0 byte n CS_N CHKSUM (1) CHKSUM (1) SPI write access CS_N MOSI ChipID1 ChipID0 MISO IRQID1 IRQID0 CONTROL DATA SPI read access Note: 26 1. Only send if chksum_ena bit set to 1 in the Ctrl register ATA6870N [DATASHEET] 9317D–AUTO–07/15 .... 7.6.4.2 Identification Field Atmel ATA6870N Chip Identification The two chip identification bytes are sent over MOSI to the Atmel® ATA6870N(n) in the chain. The ATA6870N(n) checks the LSB. When LSB=1, the information is for this device. The SPI address will be decoded and the information processed. Independent from this the identification bytes are shifted by one bit to the right and transferred to the next ATA6870N(n) in the chain. The 2 identification bytes allows the identification of up to 16 ATA6870Ns. Figure 7-15. Identification Field: Chip-ID Reception IDENTIFICATION FIELD CS_N ATA6870N (1) MOSI_IN 0x00 0x08 CONTROL DATA ATA6870N (2) MOSI_IN 0x00 0x04 CONTROL DATA ATA6870N (3) MOSI_IN 0x00 0x02 CONTROL DATA ATA6870N (4) MOSI_IN 0x00 0x01 CONTROL DATA ATA6870N (n>4) MOSI_IN 0x00 0x00 CONTROL DATA ATA6870N (1->3) identification field has lsb = 0 => device is not affected. ATA6870N (4) identification Shift it ”on the fly” once field has lsb = 1 => decode to the right SPI access. Shift it ”on the fly” once to the right ATA6870N (>4) identification field has lsb = 0 => device is not affected. Shift it ”on the fly” once to the right ATA6870N [DATASHEET] 9317D–AUTO–07/15 27 7.6.4.3 ATA6870N IRQ Identification Figure 7-16. IRQ Propagation Scheme IRQ_IN IRQ ≥1 irq_int ATA6870N (n) IRQ_IN IRQ ≥1 irq_int ATA6870N (n-1) IRQ_IN MCU IRQ ≥1 irq_int ATA6870N (1) ATA6870N(n) IRQ output is connected to ATA6870N(n-1) IRQ_IN input. ATA6870N(n-1) IRQ output is a logic OR between IRQ_IN and its internal irq_int signal. ATA6870N(1) IRQ output is connected to MCU. Figure 7-17. Identification Field: Interrupt State Emission CS_N ATA6870N (1) MISO 0x20 0x00 ATA6870N (2) MISO 0x40 0x00 ATA6870N (3) MISO 0x80 0x00 ATA6870N (16) MISO 0x00 0x00 ATA6870N (3) IRQ is set. => ATA6870N (3) sets the MSB of the first byte to be shifted out. Others bits are those coming from upper ATA6870, shifted once to the right. 28 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Master SPI receives identification word = 0x2000 = 213 = 2m. This means ATA6870N number (16-m = 16-13) = 3 has IRQ pending. Others ATA6870Ns assert the MSB of the first byte to 0. Others bits are those coming from upper ATA6870N, shifted once to the right. Note: n = IC number m = bit number m = n -1 1 < = n < = 16 0 < = m < = 15 With each SPI access, a 16- bit IRQ state is send via MISO synchronous to the identification field to the MCU with the interrupt state of all stacked Atmel ATA6870N. The MCU, interrupted by an ATA6870N, has to send the identification field to check the IRQ levels (in that case the checksum is not considered). It is also possible to continue the transaction with CONTROL and DATA field. The MCU decodes the identification field shifted in MISO input. When bit m is set, ATA6870N(16-m) is requesting interrupt. Figure 7-18. Identification Field CS_N SCK MOSI M(16) M(15) M(14) M(13) M(12) M(11) M(10) M(9) MISO I(1) I(2) I(3) I(4) I(5) I(6) I(7) M(8) M(7) M(6) M(5) M(4) M(3) M(2) M(1) I(8) I(9) I(10) I(11) I(12) I(13) I(14) I(15) I(16) 7.6.4.4 CONTROL Field The CONTROL field defines the register to access and the direction (read/write). The size of the data (8, 16, or 112 bits) is defined by the address value in the CONTROL field. Table 7-15. Control Field CONTROL Field Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 A6 A5 A4 A3 A2 A1 A0 W/Rd 7.6.4.5 DATA Field The DATA field can be composed of 1, 2, or 14 bytes depending on the accessed register. Irrespective of the data direction, a byte is always transmitted with MSB first; a multi-byte word is transmitted with MSByte first. Figure 7-19. CONTROL and DATA Fields - 8-bits Register Write CS_N SCK MOSI A(6) A(5) A(4) MISO A(3) A(2) A(1) A(0) 1 D(7) D(6) Data not relevant D(5) D(4) D(3) D(2) D(1) D(0) D(1) D(0) Data not relevant Figure 7-20. CONTROL and DATA Fields - 8-bits Register Read CS_N SCK MOSI MISO A(6) A(5) A(4) A(3) A(2) A(1) Data not relevant A(0) 0 Data not relevant D(7) D(6) D(5) D(4) D(3) D(2) ATA6870N [DATASHEET] 9317D–AUTO–07/15 29 Figure 7-21. CONTROL and DATA Fields - 16-bits Register Write CS_N SCK MOSI A(6) A(5) A(4) A(3) A(2) A(1) A(0) MISO 1 Data not relevant D(15) D(14) D(13) D(12) D(11) D(10) D(9) D(8) Data not relevant D(7) D(6) D(5) D(4) D(3) D(2) D(1) D(0) Data not relevant Figure 7-22. CONTROL and DATA Fields - 16-bits Register Read CS_N SCK MOSI A(6) A(5) A(4) A(3) A(2) A(1) A(0) MISO Data not relevant 0 D(15) D(14) D(13) D(12) D(11) D(10) D(9) D(8) D(7) D(6) D(5) D(4) D(3) D(2) D(1) D(0) In order to retrieve results from all channels in one Atmel® ATA6870N without having to request for each channel, an SPI 112-bit read-only "burst access" (dataRd16Burst register; address = 0x7F) is implemented. When requested, the ATA6870N outputs its 6 voltage channels V6 to V1 and one of the two temperature channels T2 and T1 in sequence on the SPI bus. The diagrams below show the CONTROL and DATA fields of such an access. 30 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Figure 7-23. CONTROL and DATA Fields - 112-bits Register Read CS_N SCK MOSI 1 1 1 MISO 1 1 1 1 0 0 Data not relevant 0 0 0 D(11) D(10) D(9) D(8) D(7) D(6) D(5) D(4) D(3) D(2) D(1) D(0) Channel V6 CS_N SCK MOSI MISO 0 0 0 0 D(11) D(10) D(9) D(8) D(7) D(6) D(5) D(4) D(3) D(2) D(1) D(0) Channel V1 CS_N SCK MOSI MISO 0 0 0 0 D(11) D(10) D(9) D(8) D(7) D(6) D(5) D(4) D(3) D(2) D(1) D(0) Channel temperature T1 or T2 One Atmel® ATA6870N frame corresponds to the set of results obtained in one Atmel ATA6870N. An Atmel ATA6870N frame is formatted as follows: Figure 7-24. SPI Access to dataRd16burst Register 0x7F Voltage channels Temp channel 16 bit 16 bit 16 bit 16 bit 16 bit 16 bit 16 bit ADC6 ADC5 ADC4 ADC3 ADC2 ADC1 ADCT Padding: 0x00 msb 12-bit ADC data lsb When reading data of chained ATA6870N, data is transferred as follow: ATA6870N [DATASHEET] 9317D–AUTO–07/15 31 Figure 7-25. Example with two Atmel ATA6870N in a Chain CS_N SCK MOSI SPI Clock SPI Clock Rd Reg command chip1 Rd Reg command chip2 MISO ATA6870 #1 Frame ATA6870 #2 Frame 7.6.4.6 Communication Error Correct communication can be verified using various functions of the Atmel ATA6870N. For internal synchronization, it is mandatory to keep CLK running during any SPI access; CLK must be set on 4 clock cycles (at least) before SPI access starts, and must be kept on 4 clock cycles (at least) after SPI access ends up. Keeping at least 4 CLK clock cycles between two consecutive SPI accesses is mandatory. If this is not the case, the Atmel ATA6870Ns will detect an error in communication. The CommError bit will be set in the status register 0x06). Figure 7-26. SPI Access and CLK Activity CLK OFF CLK ON 4 clk_ticks CLK_OFF 4 clk_ticks 4 clk ticks SPI ACCESS SPI ACCESS The Atmel ATA6870N verifies that complete bytes (8bits long) are always transmitted. A transition starts when CS_N goes to low and it ends when CS_N goes to high. The number of clock cycles (signal SCK) is monitored during the transition. This number of clock cycles has to be modulo 8. If the CS_N length is not modulo 8 clock cycles, the bit CommError is set in the status register. This will cause an interrupt to the MCU if the CommError is not masked by the commErrorMsk bit in the IrqMask register. 7.6.4.7 CHKSUM Field The Atmel® ATA6870N provides the possibility of verifying the transmitted data using a checksum. Setting chksum_ena bit to 1 in the Ctrl register (default = 0) activates the checksum feature. The chksum field is an 8-bit checksum computed from the proceeding data (control and data fields, byte 3 to byte n-1). It is based on the polynomial x8+x2+x1+1. The way it is computed is depicted below: Figure 7-27. LFSR-based Checksum Computation F0i serial bitstream MSB first F1i z-1 F2i z-1 F3i z-1 F4i z-1 F5i z-1 F6i z-1 F6o z-1 The checksum is calculated from the CONTROL field and DATA field by a polynomial division. The DATA field can consist of 1 byte up to 14 bytes (112-bit read-only “burst access”). The IDENTIFICATION field (2 bytes) is not used to generate the checksum. The checksum is always sent by the microcontroller, independent of read write mode. The checksum is in the LFSR (linear feedback shift register) when the complete bitstream (the whole fields of the transaction) followed by 0x00 have been shifted in the LFSR. The checksum verification on the complete data transmission was OK when the complete bitstream followed by the checksum have been shifted in the LFSR, and the content of the LFSR is 0x00. If this is not the case, the receiving ATA6870N will set the chkError bit in the status register. This will cause an interrupt to the MCU if the chkError is not masked by the chkErrorMsk bit in the IrqMask register. See the example below. The checksum is serially computed from the 8-bit value 0x57. So the bitstream 0x5700 is shifted in the LFSR. The resulting checksum is [f6o, f6i, f5i … f0i] at the last shift in cycle: 32 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Table 7-16. checksum = [f6o, f6i, ... f0i] = 0xA2 5D 7D 0D Input f01 f1i f2i f3i f4i f5i f6i f6o X 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0 1 0 1 0 0 0 0 1 1 0 1 0 1 0 0 0 1 1 1 0 1 0 1 0 0 1 1 1 1 0 1 0 1 0 0 0 1 1 1 0 1 0 1 0 1 1 0 1 1 0 1 0 0 0 1 1 0 1 1 0 1 0 1 1 0 1 0 1 1 0 0 0 1 1 0 1 0 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 0 1 0 1 0 0 0 1 0 0 0 1 0 1 0x2 0xA During an SPI write access, the checksum is computed by the MCU and sent MSB first in the CHKSUM field. For an SPI read access, the checksum is computed by the Atmel® ATA6870N and is checked by the MCU. During CHKSUM, MCU has to send 0x00 on MOSI, and must check that its own LFSR equals 0x00 at the end of CHKSUM field. 7.6.4.8 Device Position For the Atmel ATA6870N (1), this is the device on the lowest level, the SPI has to work as a standard logic CMOS interface to the MCU. The SPI’s between stacked ATA6870N have to work as level-shifters based on current sources. These different physical interfaces can be selected by the Pin MFIRST. Table 7-17. Device Position MFIRST Configuration 0 ATA6870N (2) to ATA6870N (n) 1 ATA6870N (1) Table 7-18. Electrical Characteristics No. Parameters Pin Symbol Min. 12.1 High level input voltage MFIRST MFIRST 0.7 DVDD 12.2 Low level input voltage MFIRST MFIRST 12.3 Hysteresis MFIRST MFIRST 0.05 DVDD MFIRST MFIRST –1 12.4 Input current Test Conditions VMFIRST = 0V to VDVDD Typ. Max. Unit Type* V A V A V C µA A 0.3 DVDD +1 *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter ATA6870N [DATASHEET] 9317D–AUTO–07/15 33 7.6.5 Digital Inputs and Outputs 7.6.5.1 Digital Output Characteristics Digital Output Characteristics (MISO, IRQ) If the Atmel® ATA6870N is configured as first IC (master) in a string (MFIRST = 1), these pins are configured as an open drain output. If the ATA6870N is configured to be a stacked IC (MFIRST = 0), the output signals MISO and IRQ coming from the upper IC need to be transferred to the MISO and IRQ outputs of the master in the string via the MISO_IN and IRQ_IN inputs. In this case the MISO and IRQ outputs act as level shifters based on current sources. Table 7-19. Electrical Characteristics No. Parameters Test Conditions Pin Symbol 13.1 Low level output voltage IOUT = +5mA MFIRST = 1 MISO, IRQ VMISO, VIRQ 13.2 Low level output current ±0.3V, MFIRST = 0 MISO, IRQ IMISO, IIRQ 13.3 High level output current ±0.3V, MFIRST = 0 MISO, IRQ IMISO, IIRQ Min. Typ. Max. Unit Type* 0.2 VDD V A –13 –8 µA A –65 –40 µA A *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Digital Output Characteristics (MOSI_OUT, SCK_OUT, CS_N_OUT, CLK_OUT) These outputs act as level shifters based on current sources. They transfer the input signals MOSI_OUT, SCK_OUT, CS_N_OUT, CLK_OUT to the next IC above. If the ATA6870N is the IC on the top level of a string, these outputs must be connected to VDDHV. Table 7-20. Electrical Characteristics No. Parameters Test Conditions Pin Symbol Min. 14.1 Low level output current VDDHV + 1V to VDDHV + 2V (1) V(1) 14.2 High level output current VDDHV + 1V to VDDHV + 2V (1) V(1) Typ. Max. Unit Type* 25 55 µA A –1 +1 µA A *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Note: 1. MOSI_OUT, SCK_OUT, CS_N_OUT, CLK_OUT 7.6.5.2 Digital Input Characteristics Digital Input Characteristics (MISO_IN, IRQ_IN) Table 7-21. Electrical Characteristics No. Parameters Test Conditions Pin Symbol Min. 15.1 Low level input current (VDDHV + 1.4V) ±0.3V MISO_IN, IRQ_IN IMISO_IN IIRQ_IN 13 15.2 High level input current (VDDHV + 1.4V) ±0.3V MISO_IN, IRQ_IN IMISO_IN IIRQ_IN Typ. Max. 40 Unit Type* µA A µA A *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter 34 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Digital Input Characteristics (CS_N, SCK, MOSI, CLK) Table 7-22. Electrical Characteristics No. Parameters Test Conditions Pin Symbol Min. 16.1 High level input voltage MFIRST = 1 (1) V(1) 0.7 DVDD 16.2 Low level input voltage MFIRST = 1 (1) V(1) 16.3 High level input current MFIRST = 1 I(1) 16.4 Low level input current MFIRST = 1 (1) Max. Unit Type* DVDD V A 0.3 DVDD V A 50 100 µA A –130 –70 µA A 16.5 Low level input current MFIRST = 0, V(1) = 1V to 2V (1) I(1) –55 –35 µA A 16.6 High level input current MFIRST = 0 V(1) = 1V to 2V (1) I(1) –1 +1 µA A I Typ. *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter Note: 1. CS_N, SCK, MOSI, CLK 7.6.5.3 Test-mode Pins The test-mode pins ATST and PWTST have to be kept open. The test-mode pins SCANMODE, CS_FUSE, DTST and VDDFUSE have to be connected to AVSS. Table 7-23. Input Characteristics Pins SCANMODE, CS_FUSE, VDDFUSE No. Parameters 18.1 Pull-down resistor Test Conditions Pin Symbol SCANMODE, RSCANMODE, CS_FUSE RCS_FUSE Min. 50 Typ. Max. Unit Type* 200 k A *) Type means: A = 100% tested, B = 100% correlation tested, C = Characterized on samples, D = Design parameter ATA6870N [DATASHEET] 9317D–AUTO–07/15 35 7.7 Operations 7.7.1 Voltage and Temperature Measurement At startup, the Atmel® ATA6870N is supplied and is waiting for any operation request. The available operations are: ● 6 channels voltage acquisition with a temperature acquisition ● with voltage = V(MBATi+1, MBATi) (standard operation) and with voltage = V(TEMP1 or TEMP2, TEMPVSS) (standard operation) ● with voltage = V(MBATi, MBATi) (offset calibration: CalOffset operation) and with voltage = V(TEMPVSS, TEMPVSS) (offset calibration: CalOffset operation) Operation completion is flagged to the host MCU via the IRQ output in conjunction with dataRdy bit set in the status register. In order to retrieve the full results in a single access, the user has to access the dataRd16burst register (112bits). Getting the results of a single channel (voltage or temperature) is also possible. For this, first select the channel to read through the ChannelReadSel register, then retrieve the channel value through the DataRd16 register. It is not possible to order a new operation until the previous operation has been acknowledged. The host MCU acknowledges the interrupt by reading the status register. This resets the dataRdy bit as well as the IRQ output, and enables the ATA6870N to start the next operation. Writing NoOp in the Operation register during an operation running aborts the current operation. In this case, the dataRdy bit is not set and interrupt is not requested to the host MCU. The Opstatus register flags whether operation is running, aborted, ended, or no operation is running. 7.7.2 Discharge Function Each channel is independently dischargeable. Discharge is activated or deactivated by the register ChannelDischSel. 7.7.3 Low Frequency Timer Function A low frequency timer (LFT), synchronous to internal 50 kHz oscillator provides the host MCU with a low power timer, which useful to either synchronize operations in the host MCU or monitor the Atmel ATA6870N’s activity. The LFT elapsing asserts an interrupt to the host MCU if the corresponding mask bit in the IrqMask register is not set. Default is LFT not enabled. To enable the LFT, set the LFTimer_ena bit to 1 in the Ctrl register. LFT counting time is fully programmable in the register LFTimer. Changing the LFTimer register restarts the LFT if the new counting time is smaller than the current value of the LFT. Otherwise, LFT runs until it reaches the new end value. Asserting LFTRst bit in the Rstr register resets and restarts the LFT if the LFT is enabled. Otherwise, LFT is reset but not started. Each ATA6870N will assert its own interrupt when the timer elapses. Depending on how the timer is used, the host MCU may mask LFTdone interrupts in the whole ATA6870Ns chain, except the first one. As internal RC oscillators are not synchronized, this prevents the MCU from being interrupted each time one of the LFT elapses. 7.7.4 Undervoltage Detection A programmable undervoltage detection function is embedded in the ATA6870N. After being digitalized, each of the 6 voltages is compared to a programmable threshold defined in the UdvThresh register. If one of the six channels is out of the range defined by the threshold, an interrupt is requested to the host MCU if the corresponding udv mask bit is not set in the IrqMask register. The default threshold is 1.5V. As soon as MCU has acknowledged, undervoltage information is no more available to MCU, because status register is cleared when MCU reads it out. As a consequence, the next undervoltage interrupt cannot occur until the Atmel ATA6870N leaves its current undervoltage state. 36 ATA6870N [DATASHEET] 9317D–AUTO–07/15 7.8 Registers Registers are read and written through the SPI interface. Table 7-24. Register Mapping Register Address Control Field Control Field Read Mode Write Mode Register Name Access Type Function 0x00 0x00 - RevID R 8 bits Revision ID/value Mfirst, pow_on 0x01 0x02 0x03 Ctrl RW 8 bits Control register 0x02 0x04 0x05 Operation RW 8 bits Operation request 0x03 0x06 - OpStatus R 8 bits Operation status 0x04 - 0x09 Rstr W 8 bits Software reset 0x05 0x0A 0x0B IrqMask RW 8 bits Mask interrupt sources 0x06 0x0C - Status R 8 bits Status interrupt sources 0x08 0x10 - ChannelUdvStatus R 8 bits Channels undervoltage status 0x09 0x12 0x13 ChannelDischSel RW 8 bits Select channel to discharge 0x0A 0x14 0x15 ChannelReadSel RW 8 bits Select channel to read 0x0B 0x16 0x17 LFTimer RW 8 bits Low frequency timer control 0x0C 0x18 - CalibStatus R 8 bits Reserved 0x0D 0x1A 0x1B FuseCtrl RW 8 bits Reserved 0x10 0x20 0x21 UdvThresh RW 16 bits Undervoltage detection threshold 0x11 0x22 - DataRd16 R 16 bits Single access to selected channel value 0x12 0x24 0x25 ATA6870NTest RW 16 bits Reserved 0x7F 0xFE - DataRd16Burst R 112 bits Burst Access to the whole channels (6 voltage and 1 temperature) 7.8.1 Registers Content 7.8.1.1 RevID Register Table 7-25. RevId Register Overview Register RevID Address 0x00 Reset Value 7 (msb) 6 5 4 3 x x x pow_en Mfirst 2 0x02 1 0 (lsb) RevID Table 7-26. RevId Register Content Bit Field Description RevID ATA6870N revision number, revision B: 0x02 Mfirst Status input pin MFIRST pow_en Status input pin POW_EN ATA6870N [DATASHEET] 9317D–AUTO–07/15 37 7.8.1.2 Ctrl Register Table 7-27. Ctrl Register Overview Register Ctrl Address 0x01 Reset Value 0x00 7 (msb) 6 5 4 3 2 1 0 (lsb) x x x Chksum_ena LFTimer_ena TFMODE_ena x x Table 7-28. Ctrl Register Content Bit Field Description TFMode_ena 0: Prevent ATA6870N to switch to test mode 1: Not allowed for customer use LFTimer_ena 0: Disable internal low frequency timer 1: Enable internal low frequency timer Chksum_ena 0: Disable SPI transaction checksum computation/check 1: Enable SPI transaction checksum computation/check 7.8.1.3 Operation Register Table 7-29. Operation Register Overview Register Operation Address 0x02 7 (msb) 6 x x 5 4 OpMode Reset Value 3 TempMode 2 0x02 1 VoltMode 0 (lsb) OpRqst Table 7-30. Operation Register Content Bit Field Description OpRqst 0: NoOp: No Operation, or abort current operation 1: AcqRqst: Start the analog to digital conversion An interrupt is generated when data is available in DataRd16/DataRd16Burst. 00: Caloffset: select V(MBAT(i), MBAT(i)) as input of voltage channels. (offset calibration) VoltMode TempMode OpMode 01: AcqV: select V(MBAT(i+1), MBAT(i)) as input of voltage channels (default) 10: Not allowed 0: Select TEMP1 input pin as input of temperature channel 1: Select TEMP2 input pin as input of temperature channel 00: 6 voltage channels and temperature acquisition 01: 6 voltage channels acquisition only 1X: Temperature acquisition only When a conversion operation is finished and the interrupt has been acknowledged by the MCU the operation register is automatically reset to “NoOp”. Writing “NoOp” in the register when conversion operation is running, aborts the current operation. Other changes are not accepted during any operation. 38 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Figure 7-28. Typical Data Acquisition Flow ASIC3 (MFIRST = 0) ASIC2 (MFIRST = 0) ASIC1 (MFIRST = 1) Init State Opstatus = NoOP Status Cleared Init State Opstatus = NoOP Status Cleared Init State Opstatus = NoOP Status Cleared Runs Conversion Opstatus = Running Runs Conversion Opstatus = Running Runs Conversion Opstatus = Running Conversion Finished Opstatus = Result Available Status = Data Ready IRQ DATA RDY Conversion Finished Opstatus = Result Available Status = Data Ready IRQ DATA RDY Conversion Finished Opstatus = Result Available Status = Data Ready IRQ DATA RDY MCU ... Set Operation = ACQ*/CAL* Background Tasks/Idle ASIC3 Read/Check Opstatus Read/Check Status Opstatus = NoOP Status Cleared ASIC2 Read/Check Opstatus Read/Check Status Opstatus = NoOP Status Cleared Opstatus = NoOP IRQ Acknowledged Status Cleared ASIC1 Read/Check Opstatus Read/Check Status ASIC3 Burst Read Data ASIC2 Burst Read Data ASIC1 Burst Read Data ... 7.8.1.4 OpStatus Register Table 7-31. OpStatus Register Overview Register OpStatus Address 0x03 Reset Value 7 (msb) 6 5 4 3 2 x x x x x x 0x00 1 0 (lsb) OpStatus Table 7-32. OpStatus Register Content Bit Field Description OpStatus 00: No Operation 01: Operation is ongoing 10: Operation is finished, result is available 11: Operation is cancelled, result is not available ATA6870N [DATASHEET] 9317D–AUTO–07/15 39 Figure 7-29. Operation Status Register Management User reads Operation Status Register, Reset NO OP Users programs conversions operation Operation Running Users programs NoOp End of conversion Operation Aborted, Result not Available Operation Finished, Result Available User programs conversion operation or reads operation status register Status reg has been read and: User programs conversion operation or reads operation status register The OPStatus register is reset when read after a completed or aborted operation. Reading the register before starting an operation is not mandatory. Reading data conversion results or reading the OpStatus register during an operation does not affect the OpStatus register. 7.8.1.5 Rstr Register Table 7-33. Rstr Register Overview Register Rstr Address 0x04 Reset Value 0x00 7 (msb) 6 5 4 3 2 1 0 (lsb) x x x x x x LFTRst 0 Table 7-34. Rstr Register Content Bit Field Description 0: No reset 1: Low Frequency Timer software reset LFTRst LFTRst resets and restarts the low frequency timer if not disabled (LFTimer_ena = 0). 7.8.1.6 IrqMask Register Table 7-35. IrqMask Register Overview Register IrqMask Address 40 0x05 Reset Value 0x00 7 (msb) 6 5 4 3 2 1 0 (lsb) x x x chkErrorMask udvmask commErrorMask LFTdoneMask dataDryMask ATA6870N [DATASHEET] 9317D–AUTO–07/15 Table 7-36. IrqMask Register Content Bit Field Description dataRdyMask Mask data ready interrupt when set to 1 WakeupMask Mask LFTdone interrupt when set to 1 commErrorMask udvMask Mask commError interrupt when set to 1 Mask undervoltage detection interrupt when set to 1 chkErrorMask Mask checksum error interrupt when set to 1 7.8.1.7 Status Register Table 7-37. Status Register Overview Register Status Address 0x06 Reset Value 0x20 7 (msb) 6 5 4 3 2 1 0 (lsb) x TFMdeOn por chkError udv commError LFTdone dataRdy Table 7-38. Status Register Content Bit Field Description dataRdy Conversion finished LFTdone Low frequency timer elapsed commError udv Bad SPI command detected (wrong length) Undervoltage detected chkError Error on checksum check Por Power on reset detected TFMdeOn Test mode on Any bit among {dataRdy, LFTdone, commError, udv, chkError} set in the status register requests an interrupt to the external MCU if the corresponding mask bit in the IrqMask register is 0. Reading the status register acknowledges the interrupt and resets its content. Por and TFMdeOn cause no interrupt. 7.8.1.8 ChannelUdvStatus Register Table 7-39. ChannelUdvStatus Register Overview Register ChannelUdvStatus Address 0x08 Reset Value 0x00 7 (msb) 6 5 4 3 2 1 0 (lsb) x x chUdv6_stat chUdv5_stat chUdv4_stat chUdv3_stat chUdv2_stat chUdv1_stat ATA6870N [DATASHEET] 9317D–AUTO–07/15 41 Table 7-40. ChannelUdvStatus Register Content Bit Field Description chUdv1_stat 1: Undervoltage detected on channel 1 0: No undervoltage detected on channel 1 chUdv2_stat 1: Undervoltage detected on channel 2 0: No undervoltage detected on channel 2 chUdv3_stat 1: Undervoltage detected on channel 3 0: No undervoltage detected on channel 3 chUdv4_stat 1: Undervoltage detected on channel 4 0: No undervoltage detected on channel 4 chUdv5_stat 1: Undervoltage detected on channel 5 0: No undervoltage detected on channel 5 chUdv6_stat 1: Undervoltage detected on channel 6 0: No undervoltage detected on channel 6 Undervoltage is detected when voltage decreases under the threshold value defined in udvThresh register. When undervoltage is detected on a channel, the Atmel® ATA6870N requests an interrupt if the UDVmask bit in the IRQMask register is 0. 7.8.1.9 ChannelDischSel Register Table 7-41. ChannelDischSel Register Overview Register ChannelDischSel Address 0x09 Reset Value 7 (msb) 6 5 4 3 2 1 0 (lsb) x x chV6_disch chV5_disch chV4_disch chV3_disch chV2_disch chV1_disch Table 7-42. ChannelDischSel Register Content Bit Field Description chV1_disch 1: Enable voltage channel 1 discharge 0: Disable voltage channel 1 discharge chV2_disch 1: Enable voltage channel 2 discharge 0: Disable voltage channel 2 discharge chV3_disch 1: Enable voltage channel 3 discharge 0: Disable voltage channel 3 discharge chV4_disch 1: Enable voltage channel 4 discharge 0: Disable voltage channel 4 discharge chV5_disch 1: Enable voltage channel 5 discharge 0: Disable voltage channel 5 discharge chV6_disch 1: Enable voltage channel 6 discharge 0: Disable voltage channel 6 discharge The channels are dischargeable simultaneously. 42 0x00 ATA6870N [DATASHEET] 9317D–AUTO–07/15 7.8.1.10 ChannelReadSel Register Table 7-43. ChannelReadSel Register Overview Register ChannelReadSel Address 7 (msb) 0x0A 6 5 4 Reset Value 3 2 0x00 1 0 (lsb) ChannelReadSel Table 7-44. ChannelReadSel Register Content Bit Field Description 111: Value of the LFT is returned in DataRd16 register 110: Temperature channel available in DataRd16 register 101: Voltage channel6, value available in DataRd16 register 100: Voltage channel5, value available in DataRd16 register 011: Voltage channel4, value available in DataRd16 register 010: Voltage channel3, value available in DataRd16 register 001: Voltage channel2, value available in DataRd16 register 000: Voltage channel1, value available in DataRd16 register ChannelReadSel This register can be used to quickly read a single channel without using a full burst access. The value of the selected channel will be available in the DataRd16 register. The value will always be updated by writing a channel address to the ChannelReadSel register. Data in this register is not valid during ongoing data conversion. 7.8.1.11 LFTimer Register Table 7-45. LFTimer Register Overview Register LFTimer Address 7 (msb) 0x0B 6 5 4 LFTPrescaler Reset Value 3 2 0xF9 1 0 (lsb) LFTDelay Table 7-46. LFTimer Register Content Bit Field Description LFTDelay Contains the present low frequency timer delay value LFTPrescaler 0: PrescalerValue = 1 1: PrescalerValue = 6 The default timer value is 59.965s (0xF9) for fOSC = 50kHz. ATA6870N [DATASHEET] 9317D–AUTO–07/15 43 Figure 7-30. Block Diagram LFTimer LFTprescaler 50kHz /4096 LFTdelay Comp 7-bit counter /6 Delay Time elapsed clear Formula for Delay Time calculation: LFTprescaler D 1 Delay Time = ------------------------ 4096 6 LFTdelay D + 1 T OSC [Hz] The LFT can be programmed to the following values (fOSC = 50kHz): LFTprescaler = 0: LFTprescaler = 1: 0.082s <= duration <= 10.486s, Increment = 82ms 492 ms <= duration <= 62.915s, Increment = 492ms When LFT elapsed, an interrupt is requested unless LFTdoneMask bit is set in the IRQMask register. For details on the tolerances for the oscillator, see Section 7.5.6 “RC Oscillator” on page 24. Keeping at list 100 µs between two successive LFTimer register write accesses prevents internal metastability issues, which might result in bad LFTdelay decoding. 7.8.1.12 Test-Mode Register Table 7-47. Test-Mode Register 1 Overview Register TESTmode1 Address 0x0C Reset Value 0x03 7 (msb) 6 5 4 3 2 1 0 (lsb) 0 0 0 0 0 0 1 1 Table 7-48. Test-Mode Register 2 Overview Register TESTmode2 Address 0x0D Reset Value 0x07 7 (msb) 6 5 4 3 2 1 0 (lsb) 0 0 0 0 0 1 1 1 Table 7-49. Test-Mode Register 3 Overview Register UdvThresh Address 0x12 Reset value 0x0E00 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 Test-mode registers 1, 2, and 3 are reserved for the factory calibration process. They are not allowed for customer use. 44 ATA6870N [DATASHEET] 9317D–AUTO–07/15 7.8.1.13 UdvThresh Register Table 7-50. UdvThresh Register Overview Register UdvThresh Address 0x10 15 14 13 12 x x x x 11 10 9 Reset value 8 7 6 5 4 0x0570 3 2 1 0 udvThresh Table 7-51. UdvThresh Register Content Bit Field Format Description udvThresh 12 bits Threshold for undervoltage detection Default value is 1.5V (0x0570, 1392D) 1.5V = VREF (1392 – 410) / (1502 – 410) See also Section 7.5.1.2 “12 Bits Incremental ADC” on page 18. 7.8.1.14 DataRd16 Register Table 7-52. DataRd16 Register Overview Register DataRd16 Address 0x11 15 14 13 12 x x x x 11 10 9 Reset value 8 7 6 5 4 0x0000 3 2 1 0 DataRd16 Table 7-53. DataRd16 Register Content Bit Field Format Description DataRd16 12 bits Return selected channel value (see Section 7.8.1.10 “ChannelReadSel Register” on page 43) ATA6870N [DATASHEET] 9317D–AUTO–07/15 45 7.8.1.15 DataRd16burst Register Table 7-54. DataRd16burst Register Overview Register DataRd16Burst Address 0x7F 111 110 109 108 X X X x 95 94 93 92 x x x x 79 78 77 76 x x x x 63 62 61 60 x x x x 47 46 45 44 x x x x 31 30 29 28 x x x x 15 14 13 12 x x x x 107 106 105 Reset value 104 103 102 101 0x0000 100 99 98 97 96 84 83 82 81 80 68 67 66 65 64 52 51 50 49 48 36 35 34 33 32 20 19 18 17 16 4 3 2 1 0 Channel6 data 91 90 89 88 87 86 85 Channel5 data 75 74 73 72 71 70 69 Channel4 data 59 58 57 56 55 54 53 Channel3 data 43 42 41 40 39 38 37 Channel2 data 27 26 25 24 23 22 21 Channel1 data 11 10 9 8 7 6 5 Temperature data Table 7-55. DataRd16burst Register Content 46 Bit Field Format Description DataRd16burst 112bits Returns the values of all channels from one ATA6870N, including temperature measurement ATA6870N [DATASHEET] 9317D–AUTO–07/15 Figure 7-31. Application 10Ω 1kΩ 1.5kΩ VDDHVP PD_N MISO_IN MOSI_OUT SCK_OUT CLK_OUT 100nF CS_N_OUT IRQ_IN MBAT7 VDDHV MBAT6 1kΩ DISCH6 100nF VDDHVM + 33μF DISCH5 PD_N_OUT MBAT5 POW_ENA 220nF 1kΩ 100nF PWTST DISCH4 ATST MBAT4 BIASRES 1kΩ 121kΩ 100nF ATA6870N DISCH3 TEMPVREF MBAT3 TEMP2 1kΩ 100nF DISCH2 + TEMP1 MBAT2 TEMPVSS NTC 1kΩ 10μF NTC 100nF DVDD GND DVSS VDDFUSE AVSS CS_FUSE DTST MISO MOSI SCK CLK IRQ CS_N MBAT1 MFIRST DISCH1 1kΩ SCANMODE 100nF AVDD 10nF 10Ω 10Ω 1kΩ VDDHVP PD_N MISO_IN MOSI_OUT SCK_OUT CS_N_OUT 100nF CLK_OUT IRQ_IN VDDHV MBAT7 MBAT6 1kΩ DISCH6 100nF VDDHVM + 33μF DISCH5 PD_N_OUT MBAT5 POW_ENA 220nF + 1kΩ 10μF 100nF 100nF PWTST DISCH4 ATST MBAT4 BIASRES 1kΩ 121kΩ 100nF ATA6870N DISCH3 TEMPVREF MBAT3 TEMP2 1kΩ 100nF DISCH2 TEMP1 MBAT2 TEMPVSS NTC 1kΩ NTC DVDD GND DVSS VDDFUSE AVSS CS_FUSE DTST MISO MOSI SCK CLK IRQ CS_N MBAT1 MFIRST DISCH1 1kΩ SCANMODE 100nF AVDD 10nF 10Ω MISO MOSI SCK CSN CLK IRQ VDD OUT Microcontroller GND Figure 7-31 shows an application with 2 stacked Atmel® ATA6870Ns. ATA6870N [DATASHEET] 9317D–AUTO–07/15 47 8. Ordering Information Extended Type Number ATA6870N-PLQW-1 9. Package MOQ QFN48, 7 7 4,000 pieces Package Information Top View D 48 1 technical drawings according to DIN specifications E PIN 1 ID Dimensions in mm A Side View A3 A1 12 Bottom View D2 13 24 25 12 E2 COMMON DIMENSIONS 1 A 36 48 37 e L A (10:1) (Unit of Measure = mm) Symbol MIN NOM MAX A 0.8 0.85 0.9 A1 A3 0 0.16 0.035 0.21 0.05 0.26 D 6.9 7 7.1 D2 5.5 5.6 5.7 E 6.9 7 7.1 E2 5.5 5.6 5.7 L 0.35 0.4 0.45 b e 0.2 0.25 0.5 0.3 NOTE b 05/20/14 TITLE Package Drawing Contact: [email protected] 48 ATA6870N [DATASHEET] 9317D–AUTO–07/15 Package: QFN_7x7_48L Exposed pad 5.6x5.6 GPC DRAWING NO. REV. 6.543-5188.03-4 1 9.1 Markings As a minimum, the devices will be marked with the following: ● Date code (year and week number) ● 10. Atmel® part number (ATA6870N) Revision History Please note that the following page numbers referred to in this section refer to the specific revision mentioned, not to this document. Revision No. History Table 3-1 “Pin Description” on page 4 updated Figure 7-1 “Power-down” on page 9 updated Figure 7-4 “Connection with 4 Cells only” on page 12 updated 9317D-AUTO-07/15 Figure 7-5 “MCU Supply with the Internal Power Supply” on page 14 updated Figure 7-6 “MCU Supply with an External Power Supply” on page 16 updated Section 7.6.5.3 “Test-mode Pins” on page 35 u Figure 7-31 “Application” on page 47 updated 9317C-AUTO-01/15 9317B-AUTO-06/14 Section 8 “Ordering Information” on page 48 updated Section 9 “Package Information” on page 48 updated Put datasheet in the latest template ATA6870N [DATASHEET] 9317D–AUTO–07/15 49 XXXXXX Atmel Corporation 1600 Technology Drive, San Jose, CA 95110 USA T: (+1)(408) 441.0311 F: (+1)(408) 436.4200 | www.atmel.com © 2015 Atmel Corporation. / Rev.: 9317D–AUTO–07/15 Atmel®, Atmel logo and combinations thereof, Enabling Unlimited Possibilities®, and others are registered trademarks or trademarks of Atmel Corporation in U.S. and other countries. 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