LX2202 2A Li-Ion Linear Charger and Power Control ® TM P RODUCTION D ATA S HEET KEY FEATURES DESCRIPTION The LX2202 (compared to the LX2201) has improved charge and discharge mode detection circuitry. A UVLO feature prevents battery charging when VDD is less than 3.6V. The LX2202 uses three resistors to program the constant charge current level, for setting the termination charge current, and for varying the USB charge current limits. LX2202 support two types of Li-Ion battery chemistry; 4.1V and 4.2V through logical input (VM pin). The LX2202 provides a charging status indicator. The LX2202 features a pre-charge conditioning mode for batteries that have been deeply discharged and also has a top off charge mode for batteries that are left on the charger for extended periods. The LX2202 is available in a high power 4mm x 4mm, 20-pin MLP, surface mount package. Up to 2A Charge Current Internal Pass Element Can Function as a Reverse Direction Load Switch USB Compliant Charging States using optional USB input Isolated Battery Topology Low RdsON in Discharge Mode Full Capacity Charging True Charge Indicator Wall Supply Regulator Tolerance 5V + 10% Topping Charge with Voltage Monitoring Mode Improved charge/discharge mode detection circuitry Small, High Power 20-lead MLP package Selectable Li-Ion Battery for 4.1V or 4.2V Applications WWW . Microsemi .C OM The LX2202 Linear Battery Charger is a multi-state (2 stage) Li-Ion battery charger (Constant current / Constant voltage) that is designed to minimize battery charge time (even from current limited sources such as USB) and provide a simplified interface to control battery discharge. LX2202 features up to 2A charging current from an AC adapter and an isolated battery topology to minimize charge time from current limited sources such as USB. A thermal control loop maintains a safe operating temperature at all times. The LX2202 provides a seamless complete battery interface. When the input power source is removed, the LX2202 provides the discharge path for the battery with extremely low discharge impedance. This eliminates the need for external discharge switch and voltage supervisors. In USB mode, the LX2202 provides three levels of current limit: 100mA, 500mA, and off. APPLICATIONS Batteries up to 4AH Ratings (C/2) Cell Phones PDAs Charging Cradles Digital Cameras Low Cost Single Li-Ion Cell Chargers IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com Patent Pending PRODUCT HIGHLIGHT State Select Truth Table Power On/Off NU PSW VID1 VDD VID0 VM Main Internal Power Bus NU VDD LX2202 BAT VDD BAT 0 0 0 1 1 0 Charging – USB low level if using USB. 1 1 Charging – USB high level if using USB. 10µF CMP CCP CTP STAT CUS GND USB 0.1µF 10µF VID1 BAT VDD B220 Wall Adapter VID0 2.55k 105k 72.3k To VDD Charge Indicator 2.49k VDD > VBAT Switch open – charging disabled. Charging – USB high level if using USB. VBAT > VDD Switch open – discharge disabled. Switch open – discharge disabled. Battery Discharging. MOSFET fully enhanced with current flow VBAT to VDD. Battery Discharging. MOSFET fully enhanced with current flow VBAT to VDD. PACKAGE ORDER INFO LQ Plastic MLP 4x4mm 20-Pin RoHS Compliant / Pb-free -40 to 125 Copyright © 2004 Rev. 1.0a, 2006-02-09 Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX2202CLQ-TR) LX2202 TA(°C) LX2202CLQ Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 LX2202 2A Li-Ion Linear Charger and Power Control ® TM P RODUCTION D ATA S HEET VID0 VID1 PSW NU 20 19 18 17 16 VDD 1 15 NU VDD 2 14 BAT VDD 3 13 BAT VDD 4 12 BAT USB 5 11 CMP 8 9 10 STAT CCP 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. 7 CTP 6 CUS Pad Is GND WWW . Microsemi .C OM Supply Voltage (VUSB or VDD ) ..........................................................-0.3V to 7V Analog Input Signals (VIDx, VM, SNS) .............................................-0.3V to 7V Battery Charging Current (IBAT).........................................................................2A Discharge Current (IVDD)....................................................................................3A Operating Junction Temperature.................................................................. 150°C Storage Temperature Range...........................................................-65°C to 150°C USB Maximum DC Current .......................................................................500mA USB Maximum Surge Current...........................................................................2A RoHS / Pb-free Peak Package Solder Reflow Temperature (40 second maximum exposure) ...................................................... 260°C(+0, -5) VM PACKAGE PIN OUT GND ABSOLUTE MAXIMUM RATINGS LQ PACKAGE (Top View) THERMAL DATA RoHS / Pb-free 100% Matte Tin Lead Finish LQ Plastic Micro Lead Frame Quad Package 20-Pin THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 40°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. FUNCTIONAL PIN DESCRIPTION Name Description BAT Charging Output - This pin is wired to the positive terminal of the battery. (The negative battery terminal is wired to GND.) CCP Charge Current Programming Pin - A resistor (RCP) is connected between this pin and GND. The constant current is determined by the following relationship: 73200 CMP Compensation Pin – Connect a 0.1µF compensation capacitor from this pin to VDD. CTP Charge Termination Programming Pin – A resistor (RTP) is connected between this pin and GND. The termination charge current is determined by the following relationship: 5250 CUS GND PSW R CCP I BAT( MIN) = R CTP Maximum USB Current Programming Pin – A resistor (RUS) is connected between this pin and GND. The Hi Level charge current is determined by the following relationship: 1211 I USB( HIGH) = R USB Common Ground This pin is floating and will not affect performance. PMOS Switch driver – This output is designed to drive the gate of an external PMOS power switch. The driver is pulled low (PMOS on state) when VDD > VBAT. VDD Common Power Node – Connects to system power bus. VIDx State Select Input – Applying a two bit TTL compatible signal sets the desired state of the charger corresponding to the Truth Table. USB Voltage Input – Current limited USB input. Apply a USB compliant power input. VM STAT Voltage Mode Select - Selects the constant voltage charge level. Wired to USB for 4.1V and GND for 4.2V. Status - This pin is a logic high level when the battery is being charged. A low signal indicates either under voltage lockout, charge completed, or VBAT > VDD, or VID0 = VID1 = 0. Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 PACKAGE DATA NU I BAT( MAX) = LX2202 ® TM 2A Li-Ion Linear Charger and Power Control P RODUCTION D ATA S HEET ELECTRICAL CHARACTERISTICS ` ` ` Parameter Symbol MAIN CIRCUITRY Input Voltage USB Input voltage Under Voltage Charging Lockout VDD VUSB VDDUVLO Quiescent Current IGND CTP Bias Voltage CCP Bias Voltage CUS Bias Voltage CONSTANT VOLTAGE MODE VCTP VCCP VCUS Constant Voltage Charge Voltage VCVL Top Off Charge Droop Threshold CONSTANT CURRENT MODE BAT Constant Current Accuracy Conditioning Current ` ` ` ` ` ICCL 0.85 1 1.15 VVID VM = Lo; -40C to 125C VM = Hi; -40 to 125C 3.60 2.1 20 9 1.26 1.26 2.6 VDRP State Select Threshold VBAT < VCTV ; @25°C 3.0 4.6 6.0 2.8 VCTV V V V mA µA µA V V V V % VBAT VCVL A % IBAT ICCL V IBAT @25°C 35 50 65 mA IIN IIN VUSB = 5V, VDD < VUSB, VID1 = Lo VUSB = 5V, VDD < VUSB, VID1 = Hi 85 425 93 463 100 500 mA mA 4.5 5 0.4 V V VVM THERMAL SHUTDOWN Maximum Junction Temperature TJ BI-DIRECTIONAL PASS ELEMENT CONTROL Discharge Switch On Resistance RDS(ON) Charging Threshold VCHG Discharging Threshold VDCH Pass Element Switch Mode Delay tsw PSW FET DRIVER High Output Voltage VPSW Low Output Voltage VPSW ORing Resistance RPSW Switch Delay (after tsw) tPSW HEAD ROOM Copyright © 2004 Rev. 1.0a, 2006-02-09 VBAT = 0; Rising VDD VDD > VBAT VDD < VBAT VDD < VBAT, VID0 = VID1 = 0V IBAT > 100mA Units 6 6 3.85 4 40 15 4.24 4.14 98 VSTAT VSTAT Discharging headroom 4.5 4.35 Max 4.2 4.1 97 Conditioning Current Mode Threshold Voltage Charge Termination Current Accuracy USB CURRENT LIMIT USB Low Current Limit USB High Current Limit LOGIC STAT Logic High Output STAT Logic Low Output Charging headroom LX2202 Typ VUSB = 5.0V, ISTAT = -5mA VUSB = 5.0V, ISTAT = 25µA Logic Hi Logic Lo Logic Hi Logic Lo VUSB = 5.0V, IOUT = 1A, Temperature Rising 2.0 0.8 2.0 0.8 130 IBAT = -1A (Not Tested) VUSB > VBAT + VCHG VUSB < VBAT + VDCH Charge–to–discharge or Discharge–to–charge VUSB < VBAT, IPSW = 0, VBAT = 4.2V VUSB > VBAT, IPSW = 0 CPSW = 1000pF, to VPSW = (VBAT – 1V) 4.1 5 0 VDD – VBAT, IBATT = 5mA; not tested in production VBAT – VDD, IBATT = -20mA; not tested in production Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 V V 140 150 °C 130 40 60 5 150 10 mΩ mV mV µs 0.2 15 1000 V V KΩ Ns 4.2 0 10 500 65 mV 65 mV ELECTRICALS ` Min 4.16 4.06 96 ICOND VM Select Threshold Test Conditions WWW . Microsemi .C OM Unless otherwise specified, the following specifications apply over the ambient temperature 0°C ≤ TA ≤ 70°C except where otherwise noted and the following test conditions: VDD = 5.0V, VM = GND, VID0 = VID1 = VBAT, RCCP = 72.3k, RCTP = 105k, RUSB = 2.55k. Page 3 LX2202 ® TM 2A Li-Ion Linear Charger and Power Control P RODUCTION D ATA S HEET SIMPLIFIED BLOCK DIAGRAM WWW . Microsemi .C OM UVLO VID0 PSW VDD USB STAT CHARGE/ DISCHARGE CONTROL 0.1 BAT CHARGE TERMINATION CONTROL CUS VID1 VM CTP USB LIMIT CONTROL CONSTANT VOLTAGE CONTROL CMP TEMPERATURE CONTROL CCP CONSTANT CURRENT CONTROL GND Figure 1 – Simplified Block Diagram BLOCK DIAGRAM Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 4 LX2202 ® TM 2A Li-Ion Linear Charger and Power Control P RODUCTION D ATA S HEET APPLICATION CIRCUITS WWW . Microsemi .C OM LX 2202 C O N T R O L F LO W D IA G R A M R E T U R N T O S T A R T IF V S Y S > V B A T, U V LO O R E N C H A N G E STATE. START YES U V LO NO VSYS VBAT > NO YES V ID 0 = 1 NO YES NO V ID 1= 1 YES NO EN = HI NO V B A T > 60% C O N D IT IO N CHARGE MODE YES D IS C H A R G E MODE YES CONSTANT CURRENT CHARGE MODE U S B P R O G D E TE R M IN E D B Y T H E S T A T E O F V ID 1. TEM P < TEM P < 140 NO REDUCE CHARGE CURRENT IU S B < PROG NO REDUCE CHARGE CURRENT YES NO 140 NO REDUCE CHARGE CURRENT YES YES IU S B < PROG S W ITC H O F F NO REDUCE CHARGE CURRENT YES NO I B A T < I M IN VBAT> V CV YES V O LT A G E M O N IT O R IN G M O D E (S T A T E ). YES V B A T <97% APPLICATIONS C O N S T A N T V O LT A G E CHARGE MODE NO YES RETURN TO THE TOP OF THE CHART. Figure 2 – Control Flow Diagram Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 5 LX2202 ® TM 2A Li-Ion Linear Charger and Power Control P RODUCTION D ATA S HEET APPLICATION SCHEMATICS WWW . Microsemi .C OM USB Lo / Hi NU PSW VDD VID1 VID0 VM To System Power Bus NU B220 LX2202 VDD AC/DC Adapter USB CMP CCP CTP STAT BAT CUS 1N5817 BAT VDD GND 1N4148 10µF BAT VDD 0.1µF 2.55k USB POWER 105k 72.3k IRLMS6802 Charge Indicator 10µF 2.49k State Select Truth Table VID1 0 0 VDD > VBAT Switch open – charging disabled. Charging – USB high level if using USB. 0 1 1 0 Charging – USB low level if using USB. 1 1 Charging – USB high level if using USB. VBAT > VDD Switch open – discharge disabled. Switch open – discharge disabled. Battery Discharging. MOSFET fully enhanced with current flow VBAT to VDD. Battery Discharging. MOSFET fully enhanced with current flow VBAT to VDD. APPLICATIONS VID0 Figure 3 – AC Adapter and USB Supply (Charge and Discharge Modes) (1N4148 and IRLMS6802 are optional to lower USB voltage drop.) Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 6 LX2202 2A Li-Ion Linear Charger and Power Control ® TM P RODUCTION D ATA S HEET TERMINATION CURRENT OVER TEMP 54 Termination Current (mA) 101.5 101 100.5 100 99.5 99 98.5 98 -55 -35 -15 5 25 45 65 WWW . Microsemi .C OM Normalized Current Accuracy (%) CHARGING CURRENT ACCURACY OVER T E M P 52 50 48 46 44 42 40 -55 85 -35 -15 5 25 45 65 85 Am bient Tem perature (°C) Ambient Temperature (°C) CONSTANT CURRENT PROGRAMMING TERMINATION CURRENT VS CTP CONDUCTANCE 2500 Termination Current (in mA) Constant Charge Current (mA) 600 2000 1500 1000 500 0 0.00 500 400 300 200 100 0 5.00 10.00 15.00 20.00 25.00 30.00 35.00 0.0 20.0 40.0 60.0 80.0 100.0 120.0 CCP Current (uA) CTP Conductance (in micromhos) CHARGING CURRENT OVER VDD VOLTAGE DISCHARGE MODE DYNAMIC RESPONSE 1000 800 600 CHARTS Charge Current (in mA) 1200 VDD = 4.3V VDD = 4.5V 400 VDD = 5.0V VDD = 5.5V 200 0 3 3.5 4 4.5 Battery Voltage Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 7 LX2202 2A Li-Ion Linear Charger and Power Control ® TM P RODUCTION D ATA S HEET CHARGING PROFILE DISCHARGE VOLTAGE DROP 5 1000 WWW . Microsemi .C OM 800 3 600 2 400 1 200 Voltage Drop (in mV) 4 Battery Current (mA) Stat Voltage Battery Voltage 250 200 150 100 50 0 0 0 50 100 150 200 500 250 1000 1500 2000 Discharge Current T im e (in m in u te s ) HEADROOM CONTROL Headroom vs Battery Current Vdd - Vbat (in mV) 80 60 40 20 0 -20 -40 -60 -80 -100 -50 0 50 100 Current Flow Into Battery (mA) CHARTS Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 8 LX2202 ® TM 2A Li-Ion Linear Charger and Power Control P RODUCTION D ATA S HEET THEORY OF OPERATION TOP OFF CHARGE MODE The LX2202 is designed to charge a single cell Lithium Ion battery using two steps: a constant current step followed by a constant voltage step. The basic charger function uses the VDD pins as an input and BAT pins as the output. The LX2202 charger has a programmable maximum current (programmable by the resistor value between pin CCP to GND) which is the maximum charging current during the Constant Current Mode of the charging profile. The low dropout of the pass element allows the battery to be charged from a loosely regulated power supply. In the Constant Voltage Mode, the battery terminal voltage can be regulated to 4.1V or 4.2V by strapping the VM pin to VDD or GND, respectively. The charger will terminate constant voltage charging once the current drops below the minimum current setting (programmable by the resistor value between pin CTP to GND). The LX2202 has an integrated thermostat with a linear thermal regulation loop that will throttle back the charging current to prevent the internal die temperature from exceeding 150ºC. This feature prevents damage to the system board when the IC exceeds its thermal temperature. Once the charger has completed a charge cycle, if power remains applied, the LX2202 enters a Voltage Monitoring mode. In this mode the LX2202 monitors the battery terminal voltage and applies a top off charge if the battery voltage drops by more than 3% of full scale. This feature is especially important for charging systems in equipment where usage is infrequent. 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 CCP programmable constant current level (except where it might be limited in the USB states). Once the battery terminal voltage exceeds the 60% level, the full constant current level is applied (unless charging current is limited by one of the other charger control loops). The LX2202 is fully compliant with, and supports, the USB specifications – the Low Power Peripheral (100mA) and High Power Peripherals (500mA). VID1 logic input selects USB charge currents. The LX2202 senses the current flowing from the USB terminal to the VDD terminal; then it limits the USB current by reducing the current flowing from VDD to VBAT. DISCHARGE MODE VID0 is used to enable discharge mode enable. The system load is connected to VDD. The input power is connected to VDD through an external diode. When the input power is removed, the battery current flows from VBAT to VDD. The circuit of Figure 3 shows the LX2202 in a discharge mode configuration with both AC adapter and USB inputs. The USB input is diode ORed to the VDD pin and uses a MOSFET to reduce the diode drop across the ORing diode. The LX2202 provides a signal “PSW” to control the MOSFET for charge and discharge modes. When both AC and USB power are applied the PSW signal is overridden by the AC adapter diode and the MOSFET is turned off UNDER VOLTAGE LOCK OUT CHARGE TERMINATION MODE The LX2202 has an under voltage lock-out feature that monitors the VDD terminal and prevents the battery charger from entering charge mode if the VDD terminal is less than 3.6V (nominal). Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 APPLICATIONS To increase system battery life and avoid float charging, the LX2202 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 charge status changes state when charging is completed. Copyright © 2004 Rev. 1.0a, 2006-02-09 USB CHARGE MODE WWW . Microsemi .C OM GENERAL DESCRIPTION Page 9 LX2202 ® TM 2A Li-Ion Linear Charger and Power Control P RODUCTION D ATA S HEET APPLICATION NOTE USB COMPLIANCE The LX2202 has an isolated battery topology which reduces charge time from USB when the appliance is turned on while also charging. Because the system power rail can be a higher voltage than the battery voltage, the system will require less power from the USB source which leaves more power available to charge the battery which charges the battery faster. For example, if the system draws 1W, and the USB input is 5V, the system draws 1W/5V = 200mA from the USB source; this leaves 300mA to charge the battery. In a topology where the load connects directly to the battery (as is done with conventional linear chargers), if the average battery voltage is 3.7V, the system will draw 1W/3.7V = 270mA from the USB source, this leaves only 230mA to charge the battery. In this case the LX2202 will charge the battery 30% faster. To be compliant with the USB specification, the +5V current must be less than 100mA in the low power mode and less than 500mA in the high power mode. If the LX2202 is configured as shown in Figure 3, it is possible for the system to consume more than the maximum allowed USB current (in which case the battery charging current will have been fully scaled back). If it is not possible to regulate the load current when charging from a USB power source and strict adherence to the USB power budget is required, in this case the system load can be applied directly across the battery and the LX2202 will prevent the combination of the load plus battery from drawing more power than is allowed for USB compliance. CURRENT LIMITED POWER SUPPLIES The LX2202 has special headroom voltage regulation circuitry that allows charging from current limited power sources. The LX2202 increases the impedance of the pass element under small charge or discharge currents so that mode change situations can be more readily detected by the internal circuits. This improved mode discrimination allows the battery to aid the current limited input power supply when the system load demands it and to switch back to charge mode when the system power demand is reduced. WWW . Microsemi .C OM REDUCED USB CHARGE TIME LAYOUT GUIDELINES • It is important when laying out the LX2202 to place 10µF ceramic capacitors close to the VDD and VBAT IC terminals to filter switching transients. • It is important to provide a low thermal impedance path from the thermal pad on the bottom of the LX2202 package to the ground plane of the circuit board to maximize the heat dissipation. APPLICATIONS Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 10 LX2202 2A Li-Ion Linear Charger and Power Control ® TM P RODUCTION D ATA S HEET PACKAGE DIMENSIONS 20-Pin MLPQ Plastic 4x4mm (114x114DAP) D b L D2 E E2 e A1 Dim A A1 A3 b D D2 E E2 e L MILLIMETERS MIN MAX 0.80 1.00 0.00 0.05 0.20 REF 0.18 0.30 4.00 BSC 2.59 2.79 4.00 BSC 2.59 2.79 0.50 BSC 0.30 0.50 INCHES MIN MAX 0.031 0.039 0.000 0.002 0.008 REF 0.007 0.088 0.157 BSC 0.102 0.110 0.157 BSC 0.102 0.110 0.019 BSC 0.011 0.019 WWW . Microsemi .C OM LQ A A3 MECHANICALS Copyright © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 11 LX2202 TM ® 2A Li-Ion Linear Charger and Power Control 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 © 2004 Rev. 1.0a, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 12