LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET KEY FEATURES DESCRIPTION Two Independent Programmable Charge Currents 0.5% Float Voltage Tolerance Charging up to 1A. Charging from USB Port. USB Current Compliance Full Battery Indicator CC/CV w Thermal Feedback Battery Temperature Monitor Precision Charge Termination Power Good Indication The LX2206 enters a low quiescent current sleep mode when power is removed or when it is logically shutdown to minimize battery drain. There are several protection features which include: under voltage lock out, inrush current limiting, reverse current blocking on the IN pin, a thermal loop to reduce charge current to maintain a low die temperature, an unsafe battery temperature charge inhibitor, and conditioning mode is provided for deeply discharged batteries. WWW . Microsemi .C OM The LX2206 can be used with a wall adapter or USB power source to charge a single cell Lithium Ion or Lithium Polymer battery. There are two logic selectable and programmable charge current levels which can be set from anywhere between 50mA to 1A. The termination current is 1/10 the charge level set by the High Level Programming Current Pin. Power status indicators (STAT and DCOK) can be configured to show charge in progress, battery fully charged and external power on. The STAT pin is capable of sourcing or sinking 10mA. The DCOK output is an open drain output. APPLICATIONS MP3 Player PDA PMC Digital Camera Charge Cradle IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com PRODUCT HIGHLIGHT Status Charging STAT IN Adapter or USB CMP Shutdown SD High/Low Charge Current H/L Control Logic Full DCOK Power On LX2206 DCOK TMP HCP LCP BAT GND Current Programming Battery Battery Temperature Lockout Sensing LX2206 PACKAGE ORDER INFO TA (°C) LD Plastic MLPD 10-Pin RoHS Compliant / Pb-free -40 to 85 LX2206ILD Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX2206ILD-TR) Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET ABSOLUTE MAXIMUM RATINGS PACKAGE PIN OUT 10 BAT 9 TMP 8 HCP DCOK 4 7 LCP SD 5 6 H/L IN 1 CMP 2 STAT 3 Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of specified terminal. CONNECT BOTTOM PAD TO GND LD PACKAGE PINOUT (Top View) RoHS / Pb-free 100% matte Tin Pin Finish WWW . Microsemi .C OM Supply Input Voltage (IN, BAT) ...................................................................... -0.3V to 7V All other pins ............................................................................................-0.3V to VSUPPLY Battery Charging Current .............................................................................................1.1A Operating Temperature Range .........................................................................-40 to 150°C Maximum Operating Junction Temperature .............................................................. 150°C Storage Temperature Range.........................................................................-65°C to 150°C Lead Temperature (Soldering 10 seconds)................................................................. 300°C Package Peak Temp. for Solder Reflow (40 seconds maximum exposure) ... 260°C (+0 -5) THERMAL DATA 2206 xxxx MSC LD Plastic Micro Leadframe Package 10-Pin THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 33°C/W Junction Temperature Calculation: TJ = TA + (PD x θJA). The θJA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. Part Marking xxxx = Denotes date and lot code Identification ` FUNCTIONAL PIN DESCRIPTION Name Description BAT Battery – Connect to a single cell Lithium Ion Battery. CMP Compensation – Connect the series combination of a 1k resistor and a 0.47µF capacitor from CMP to IN. DCOK Power status logic pin and LED driver – This pin is an open drain output that can sink 20mA of current to drive an external LED. This pin is low impedance to GND when the Input voltage is high enough to charge the Battery. GND Ground – Connect to the system ground plane. Use sufficient via copper area to allow for thermal conduction from the IC to the GND plane. HCP High Current Programming (and Termination Current Programming) – Connect a resistor to ground to set the constant current high level. The termination current is set to 1/10 of the High Current Programming Level. For a value of 19.6K, the High Current is 460mA and the Termination Current is 46mA. H/L High or Low load select logic input – A logic high selects the constant charge current level set by the HCP pin resistor and a logic low selects the constant charge current level set by the LCP pin resistor IN Input Power – Connect to a wall adapter or a USB power plug. Low Current Programming – Connect a resistor to ground to set the constant current low level. For a value of 110K, the Low Current is 92mA. SD Shutdown – A logic high places the LX2206 in sleep mode; can also be used for USB suspend. STAT Charging status logic pin and LED driver – This pin can source or sink 10mA of current to drive an external LED in either output state. This pin is low (current sinking mode) when the battery is in charging mode and becomes high (current sourcing mode) when the charge cycle is finished. It becomes a high impedance when the input power is removed. TMP Battery Temperature Monitor – This sense pin determines the battery temperature for charging out of temperature range lockout and is connected to a resistor network as defined in the Applications section. The TMP pin is grounded if this function is not used. Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 PACKAGE DATA LCP LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET -- ` Parameter Symbol INPUT CIRCUITRY Input Voltage Battery Voltage Under Voltage Charging Lockout UVLO Hysteresis VIN VBAT VINUVLO Input Supply Current ` ` IIN BATTERY CHARGER Constant Voltage Charging Constant Voltage Charging HCP Bias Voltage LCP Bias Voltage VCVL VCVL VHCP VLCP Battery Charge Current IBAT Conditioning Current Conditioning Current Cond. Current Threshold Charge Termination Current Charge Termination Current Charge Termination Current ICOND ICOND VCCT IBAT IBAT IBAT Top Off Threshold VTOT Battery Drain Current IBAT LOGIC STAT Logic High Output STAT Logic Low Output VDRV VDRV Input Logic : SD, H/L VLOG(IN) Input Current : SD, H/L ILOG(IN) VLOG(OUT) Output Logic : DCOK ` Test Conditions Min LX2206 Typ 4.35 Rising input VBAT = 3.2V 3.5 VBAT = 4.2V; battery charged SHDN = High IBAT < 100mA IBAT < 100mA @ 25C IBAT > 100mA 4.16 4.18 HCP = 12.1k 650 420 87 13 2.6 2.5 34 H/L = Low VBAT < VCCT; HCP = 19.6k VBAT < VCCT; HCP = 110k HCP = 19.6k HCP = 110k HCP = 210k 96 VBAT = 4.2V; battery charged VBAT > VIN SD = High (Shutdown Mode) VIN = 5.0V, IDRV = -10mA VIN = 5.0V, IDRV = 10mA Logic Hi, Logic Lo Logic Hi, VLOG = 2V Logic Lo, VLOG = 0V Logic Hi, ILOG = 10k pullup to 3.3V Logic Lo, ILOG = 20mA 4.2 3.8 300 1 35 Max 6 4.3 4 4.2 4.2 1.25 1.25 710 460 92 23 5.0 2.7 46 9 5 4.24 4.22 97 1 5 1 98 30 30 5 4.5 5 0.5 2 0 V V V mV mA µA 2 50 V V V V mA mA mA mA mA V mA mA mA 750 483 97 33 7.5 2.9 59 1.2 0 -2 3.1 Units 0.4 4 2 0.5 WWW . Microsemi .C OM ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating ambient temperature -40°C ≤ TA ≤ 85°C except where otherwise noted and the following test conditions:. IN = 5.0V; SD = Low; H/L = High; BAT = 3.6V; HCP =19.6k, LCP=110k; TMP = 0V. % VBAT VCVL µA µA µA V V V µA V BATTERY TEMPERATURE MONITOR VCOLD Hot Temp Fault Threshold VHOT TFB Disable Voltage VDIS Copyright © 2007 Rev. 1.3a, 2007-08-28 Rising Threshold Falling Threshold Falling Threshold Rising Threshold 75 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 0.75 x VIN 0.72 x VIN 0.28 x VIN 0.30 x VIN 100 150 V V V V mV ELECTRICALS Cold Temp Fault Threshold Page 3 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET SIMPLIFIED BLOCK DIAGRAM WWW . Microsemi .C OM + SD ENABLE DCOK UVLO STAT TMP CHARGE CONTROL BAT IN CHARGE TERMINATION CONTROL CONSTANT VOLTAGE CONTROL TEMPERATURE CONTROL CONDITIONING THRESHOLD H/L COND. CURRENT LCP HCP LOW CHARGING CURRENT BLOCK DIAGRAM HIGH CHARGING CURRENT GND Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 4 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET CONTROL LOGIC DIAGRAM WWW . Microsemi .C OM RETURN TO START IF VIN > VBAT, UVLO, SD, CHANGE STATE. START YES SD NO V IN > V BAT NO SLEEP YES YES UVLO NO VOLTAGE MONITORING M ODE (STATE). V BAT <97% NO YES V BAT >60% NO CONDITION CHARGE MODE CONSTANT VOLTAGE CHARGE MODE YES CONSTANT CURRENT CHARGE M ODE I M AX DETERM INED BY THE STATE OF H/L, R HC P , R LC P . TEM P < 130 REDUCE CHARGE CURRENT NO YES TEM P < 130 NO YES < I M AX I CC< I M AX REDUCE CHARGE CURRENT NO YES REDUCE CHARGE CURRENT NO I BAT <ITAPER YES APPLICATIONS I CC NO REDUCE CHARGE CURRENT ITAPER DETERM INED BY R H CP . YES NO V BAT > V CV RETURN TO THE TOP OF THE CHART. YES Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 5 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION CIRCUITS WWW . Microsemi .C OM Figure 1 – Typical Application – 1A or 500mA maximum charge currents with three indicators and battery temperature lockout. A grounded spare pin in the USB power cable can be used to sense when the 500mA USB current power source is being used. 15k USB 1k 0.47uF IN STAT Charging 2.5k CMP Suspend SD USB High/Low H/L 10k LX2206 DCOK LCP 19.6k Current Programming DCOK TMP HCP Control Logic VCC BAT GND 110k Battery Figure 2– Typical USB Application – 500mA or 100mA maximum charge currents with charge indicator. 15k Adapter 1k 0.47uF IN STAT CMP SD H/L 10k LX2206 DCOK 17.8k DCOK TMP HCP LCP VCC APPLICATIONS Shutdown Charging 2.5k BAT GND 63.4k Battery Figure 3 – Typical Low current application – 150mA charge current and 50mA termination current. Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 6 LX2206 TM ® Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET THEORY OF OPERATION CONDITIONING CURRENT CHARGE MODE A conditioning current is applied to batteries that are deeply discharged and have a terminal voltage less than 60% of the constant voltage level. The conditioning current is 5% of the HCP programmable constant current level. Once the battery terminal voltage exceeds the conditioning current threshold, the full constant current level is applied (unless charging current is limited by one of the other charger control loops). CHARGE TERMINATION MODE To increase system battery life and avoid float charging, the LX2206 turns off the pass element once the battery has been fully charged. The charge termination state occurs at the end of constant voltage mode. The termination current is set by the value of the resistor connected to the HCP programming pin. The STAT pin changes state when charging is completed. TOP OFF CHARGE MODE Once the charger has completed a charge cycle, if power remains applied, the LX2206 enters a Voltage Monitoring mode. In this mode the LX2206 monitors the battery terminal voltage and applies a top off charge if the battery voltage drops below the top of threshold. The LX2206 supports battery charging from a system that provides adapter power or USB power using the same external connector. Figure 1 shows one example of a system using a special USB adapter cable to determine whether the power source is USB or Wall Adapter. Similarly, if the system processor senses the absence of USB data, it can logically set the H/L logic level high to allow a higher charge current to be used. USB CHARGE MODE AND CURRENT LIMIT The LX2206 is fully compliant with, and supports, the USB specifications – the Low Power Peripheral (100mA) and High Power Peripherals (500mA). USB current levels can be set using the appropriate values for the HCP and LCP programming resistors. H/L logic input selects USB high/low charge currents. When the SD pin is pulled high, the USB input enters Suspend mode and will not present a load to the IN pin. DCOK The IN input is monitored and DCOK is set to a logic low to report the presence of the power source with sufficient voltage to charge the battery. The DCOK threshold is the larger of the UVLO threshold or the battery voltage. PROTECTION FEATURES Conditioning Current Mode – If the battery terminal voltage is less than 2.7V, the battery charger will reduce the charge current to 5%. This also protects the appliance from overheating by trying to drive the full charging current into a short circuited battery. Under Voltage Lockout – The charge cycle will not start until the IN voltage rises above 3.8V. Hysteresis helps alleviate chattering on and off. Thermal Control loop – If the power dissipation of the charger becomes excessive, the charge current will be reduced to prevent the die temperature from getting above 140°C. This does not cause the charge cycle to stop. Reverse current blocking – If IN input is grounded, current will not flow from the BAT pin through the charger. No external blocking diode is required on the input. Sleep Mode – If the SD pin is a logic high, the charger enters a sleep mode where a very low quiescent current prevents drain from the battery. Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 7 APPLICATIONS Copyright © 2007 Rev. 1.3a, 2007-08-28 ADAPTER OR USB SELECTION WWW . Microsemi .C OM GENERAL DESCRIPTION The LX2206 is designed to charge a single cell Lithium Ion battery using two steps: a constant current mode followed by a constant voltage mode. The maximum charging current during the Constant Current Mode of the charging profile can be logically set (using H/L) to two preprogrammed levels set by resistors connected to HCP and LCP (High and Low current). The charger will terminate constant voltage charging once the current drops below the taper current setting which is 10% of the high charge current setting (determined by HCP resistor value). LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION NOTE IHCP The termination current determines the point at which the charge cycle is terminated and the battery is determined to be fully charged. The termination current is determined by the value of the HCP programming current as determined by the HCP programming resistor. For a value of IHCP = 11.4µA (as was used in the previous example), the termination current from the chart below can be seen to be 9mA. Term ination Current vs IHCP 120 Termination Current (in mA) CURRENT PROGRAMMING RESISTORS The LX2206 has two programming resistors to control the battery charging current during the constant current charging mode of the battery charging cycle. When the H/L pin is high (selecting the High Current charging mode), the charge current is determined by the value of the HCP programming resistor. The maximum charge current is determined by the programming current at either the HCP or LCP programming pins (depending on the state of H/L); the range of each of these channels is identical. The programming current is the HCP or LCP pin voltage (typically 1.25V) divided by the value of the programming resistor. For example, the HCP current with a 110K resistor to GND is: Using the table below it can be seen that for a programming current value of 11.4µA, the corresponding maximum charge current is 92mA. WWW . Microsemi .C OM LAYOUT In the layout of the Printed Circuit Board (PCB) it is important to provide a solid path from the IC power and ground pins to the power and ground planes of the PCB to provide a good conduction path for heat. This insures the LX2206 stays cool and can provide the maximum charge current to minimize the time required to charge the battery. For stability purposes and to reduce voltage switching transients it is important to place capacitors close to the IN and BAT pins. A 10µF capacitor (X5R or X7R dielectric) is recommended. 1.25 1.25 = = = 11.4µA RHCP 110k 100 80 60 40 20 0 0.00 50.00 100.00 150.00 IHCP (in uA) Charge Current vs IHCP (or ILCP) The termination current is always roughly 10% of the maximum charge current set by the HCP resistor. 1000 800 600 APPLICATIONS Charge Current (in mA) 1200 400 200 0 0.00 50.00 100.00 150.00 IHCP (in uA) Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 8 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION NOTE WWW . Microsemi .C OM BATTERY TEMPERATURE MONITOR The LX2206 has an input to monitor the battery temperature during battery charging; this method assumes the battery pack contains a thermistor expressly for this purpose. A typical Lithium ion battery should only be charged from a range of 0°C to 60°C. For this calculation, a Vishay NTHS0402N01N1003J Thermistor was used. This thermistor is 327KΩ at 0°C, 100KΩ at 25°C and 24.9KΩ at 60°C. The thermistor must be biased with a Thevenin voltage source and series resistance to achieve the proper thresholds. A fixed value resistor is added in series with the thermistor to prevent it from becoming too low an impedance at high temperatures and causing the TMP input to default to off. To finish the design it is necessary to create the Thevenin Voltage and resistance using a voltage divider from the input pin (IN). VIN R1 TMP RMIN R2 RNTC VTH RTH The values of R1 and R2 can be calculated as: RMIN R R1 = TH = 122K K TMP RNTC R2 = Using a value of RMIN that is equal to the thermistor temperature at 60°C works well; therefore, for this example, set the value of RMIN to 24.9K. This has the effect of adding 24.9K to the thermistor resistance values so it becomes 352KΩ at 0°C, 125KΩ at 25°C and 49.8KΩ at 60°C. R1 × RTH = 14,800K R1 − RTH In this case, it is not necessary to use R2, because the value is so large it is insignificant. In this case, R1 = RTH. The equations for RTH and VTH are: VTH 0.29 × 0.74 × (R T=0C − R T =60C ) = = K = 0.99 VIN (0.29 × R T =0C ) − (0.74 × R T =60C ) APPLICATIONS ⎛ K ⎞ R TH = ⎜ − 1⎟ × R T = 0C = 121K ⎝ 0.74 ⎠ Where R at temperature is the sum of the thermistor plus RMIN. Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 9 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION NOTE INPUT POWER SOURCE DETECTION In order to detect when the input power source has been removed, the LX2206 requires that a small current (up to 200uA) momentarily flow out of the IN pin (in the reverse direction). Once detected, the reverse IN current is shut off (the IN pin becomes a very high impedance until an input power source is later reapplied). In most applications, there is sufficient loading on the IN pin from external circuitry to accomplish this, which includes the “Full” and/or “Power On” LED loads and the TFB resistor string. If there is no external load on the IN pin, then it is recommended to provide a 15k resistor from IN to GND as shown below. VIN 121k TMP 24.9k RNTC The TMP voltages with this circuit are: TEMP (°C) -20 0 25 60 80 RNTC 971k 327k 100k 24.9k 12.6k Adapter or USB VTMP (% VIN) 89% 74% 51% 29% 24% WWW . Microsemi .C OM The final circuit for this example is: IN CMP 15k 1k 0.47uF LX2206 POWER STATUS INDICATORS The STAT pin is designed to source or sink current. LEDs can be configured to indicate charging or battery full. The battery full indicator can be connected to DCOK rather than GND to insure it is off when the input power is removed and the STAT pin and DCOK pin go to a high impedance state. Conditions Charge in process STAT Low Charge completed High Input power removed Hi Z APPLICATIONS Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 10 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET CONDITIONING CURRENT Battery Charging USB High Level Conditioning Current vs IHCP 0.50 4.25 60 0.40 4.15 0.30 Ibat 4.10 0.25 4.05 0.20 0.15 4.00 0.10 3.95 B attery C u u ren t 0.35 Vbat Conditioning Current (in mA) 0.45 4.20 B attery V o ltag e WWW . Microsemi .C OM CHARGING PROFILE 50 40 30 20 10 0.05 3.90 0.00 0.0 60.0 120.0 0 0.00 50.00 100.00 150.00 IHCP (in uA) Time in minutes FLOAT VOLTAGE TERMINATION CURRENT CHARTS Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 11 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET CONSTANT CURRENT CONDITIONING CURRENT WWW . Microsemi .C OM CHARTS Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 12 LX2206 ® TM Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET PACKAGE DIMENSIONS WWW . Microsemi .C OM LD 10-Pin Plastic MLP Dual Exposed Pad D e L E E2 Top View Bottom View b D2 A A3 A1 MILLIMETERS MIN MAX 0.80 1.00 0 0.05 0.20 REF 0.18 0.30 3.00 BSC 2.23 2.48 0.50 BSC 3.00 BSC 1.49 1.74 0.30 0.50 INCHES MIN MAX 0.0315 0.0394 0 0.0019 0.0079 REF 0.0071 0.0118 0.1181 BSC 0.0878 0.0976 0.0197 BSC 0.1181 BSC 0.0587 0.0685 0.0071 0.0197 Note: 1. Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006”) on any side. Lead dimension shall not include solder coverage. Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 13 MECHANICALS Dim A A1 A3 b D D2 e E E2 L LX2206 TM ® Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET NOTES WWW . Microsemi .C OM NOTES PRODUCTION DATA – Information contained in this document is proprietary to Microsemi and is current as of publication date. This document may not be modified in any way without the express written consent of Microsemi. Product processing does not necessarily include testing of all parameters. Microsemi reserves the right to change the configuration and performance of the product and to discontinue product at any time. Copyright © 2007 Rev. 1.3a, 2007-08-28 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 14