Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET KEY FEATURES DESCRIPTION LX2201 support two types of Li-Ion battery chemistry; 4.1V and 4.2V through logical input (VM pin).. A high accuracy current sensing circuit allows batteries to be fully charged before terminating the charge cycle. The LX2201 design enhances system battery life by avoiding premature discharge of Li-Ion battery with a separate battery terminal voltage from system load when adaptor charging is used, i.e. trickle charge. The LX2201 provides a charging status indicator. The integrated PMOS pass element features low drop out voltage while providing an inherent load disconnect with virtually no drain on the battery when disabled or when the input power is removed. Additionally a battery load disconnect switch has been integrated which provides seamless power switching when transitioning between charge and discharge modes. The LX2201 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 LX2201 is available in a high power 4mm x 4mm, 20-pin MLP, surface mount package. 2A Charge Current USB Compliant Charging States Low RdsON in Discharge Mode Power Saving and Conditional Mode for Deep Discharge Selectable Li-Ion Battery for 4.1V or 4.2V Applications Internal Pass Element Can Function as a Reverse Direction Load Switch No Sense Resistor Required Full Capacity Charging True Charge Indicator Wall Supply Regulator Tolerance 5V + 10% Built In MOSFET Driver For Easy AC Adapter/USB Implementation Topping Charge with Voltage Monitoring Mode Inherent Load Disconnect Small, High Power 20-lead MLP package WWW . Microsemi .C OM The LX2201 Linear Battery Charger is a multi-state (2 stage) Li-Ion battery charger (Constant current / Constant voltage) that can supply up to 2A of charging current into a single cell Li-Ion battery. LX2201 is a cost effective, high performance USB battery charger. The LX2201 features a 2A high charge current, with automatic power savings using isolated battery topology, user programmability in USB charging, and an extended battery life with low RdsON in discharge. In USB mode, the LX2201 has advantages over competition chargers with the USB Limit Control circuit and low RdsON in discharge mode. The USB limit Control circuit allows simultaneous battery charging while the device is in operation. The VDD to supply load is independent of the VBAT charging logic. In discharge mode a low RdsON provides low loss and heavy transient. The LX2201 is a low cost, highly integrated battery charger solution. . It only requires three external resistors: one for setting the constant charge current level, one for setting the termination charge current, and one for setting VIN . It also has a built in thermostat that will throttle back the charge current to keep the die temperature from exceeding 150°C; this feature insures the LX2201 delivers the maximum charge rate for a given thermal environment. APPLICATIONS Batteries with 350mAH to 2AH Ratings 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 USB Lo / Hi NC PSW VID1 VID0 VM To System Regulator BAT VDD VID1 0 0 0 1 1 0 Charging – USB low level if using VIN. 1 1 Charging – USB high level if using VIN. BAT VDD LX2201 VDD AC/DC Adapter BAT BAT VIN CMP CCP CTP CUS GND STAT VDD USB POWER VDD > VBAT Switch open – charging disabled. Charging – USB high level if using VIN. 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. LX2201 VID0 PACKAGE ORDER INFO TA(°C) LQ Plastic MLP 4x4mm 20-Pin RoHS Complaint / Pb-free 0 to 70 Copyright © 2000 Rev. 1.3, 2006-02-09 Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX2201CLQ-TR) LX2201CLQ Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET VID0 VID1 PSW N.C. 20 19 18 17 16 VDD 1 15 BAT VDD 2 14 BAT VDD 3 13 BAT VDD 4 12 BAT VIN 5 11 CMP THERMAL DATA 8 9 10 CCP GND 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 STAT 6 CTP Pad Is GND WWW . Microsemi .C OM Supply Voltage (VIN)..........................................................................-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 Peak Package Solder Reflow Temp. (40 second max. exposure) ... 260°C (+0, -5) VIN Maximum DC Current..........................................................................500mA VIN Maximum Surge Current.............................................................................2A VM PACKAGE PIN OUT CUS ABSOLUTE MAXIMUM RATINGS LQ PACKAGE (Top View) N.C. – No Internal Connection LQ RoHS / Pb-free 100% Matte Tin Lead Finish 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 65000 determined by the following relationship: I = CMP Compensation Pin – Connect a 0.1uF 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 7500 current is determined by the following relationship: I = CUS Maximum VIN Current Programming Pin – A resistor (RUS) is connected between this pin and GND. The Hi Level charge 1211 current is determined by the following relationship: I = GND Common Ground BAT(MAX) RCP BAT(MIN) IN(HI)) NC PSW RTP RUS Not Connected. This pin is connected internally and should be left floating. 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. 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. VIN Voltage Input – Current limited USB input. Apply a USB compliant power input. VM Voltage Mode Select - Selects the constant voltage. VM = Low to select 4.2V charge level. VM = High to select 4.1V charge level. STAT Copyright © 2000 Rev. 1.3, 2006-02-09 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. Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 PACKAGE DATA VDD Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET ELECTRICAL CHARACTERISTICS Parameter ` ` MAIN CIRCUITRY Input Voltage Quiescent Current IGND CTP Bias Voltage CCP Bias Voltage CUS Bias Voltage CONSTANT VOLTAGE MODE VCTP VCCP VCUS Constant Voltage Charge Level VCVL ` ` ` VDRP CONSTANT CURRENT MODE BAT Constant Current Accuracy BAT Constant Current Level ICCL IBAT ICOND 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 VSTAT VSTAT State Select Threshold VVID VM Select Threshold VVM LX2201 Typ 4.5 VDD > VBAT VDD < VBAT RCTP = 150K, IBAT > 100mA VM = Low VM = High IBAT = 1A 4 3 1.25 1.25 2.6 Max Units 6 8 5 4.16 4.06 4.2 4.1 4.24 4.14 350 96 97 98 RCCP = 64.9K VBAT < (VCVL – 100mV) 0.85 0.35 1 1.15 2 VBAT < VCTV ; @25°C 3.0 4.75 6.0 VCTV 60 64 68 V mA µA V V V V mV % VBAT VCVL A A % % IBAT ICCL VBAT VCVL IBAT RCTP = 150K ; @25°C 35 50 65 mA IIN IIN VIN = 5V, VDD < VIN, VID1 = Lo, RUSB = 2.55K VIN = 5V, VDD < VIN, VID1 = Hi, RUSB = 2.55K 85 425 93 463 100 500 mA mA 4.5 5 0.4 V V 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 OR-ing Resistance RPSW Switch Delay tPSW (VDD > VBAT to VDD < VBAT) Copyright © 2000 Rev. 1.3, 2006-02-09 Min 70°C except where VIN = 5.0V, ISTAT = -5mA VIN = 5.0V, ISTAT = 25µA Logic High Logic Low Logic High Logic Low VIN = 5.0V, IOUT = 1A, Temperature Rising IBAT = -1A VIN > VBAT + VCHG VIN > VBAT + VDCH Charge–to–discharge or Discharge–to–charge VIN < VBAT, IPSW = 0, VBAT = 4.2V VIN > VBAT, IPSW = 0 CPSW = 1000pF, to VPSW = (VBAT – 1V) 2.0 0.8 2.0 0.8 V V 130 140 150 °C 0 0 130 5 5 5 150 10 10 mΩ mV mV µs 4.1 5 4.2 0 10 0.2 15 V V KΩ 0 500 1000 Ns Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 ELECTRICALS ` VIN – VBAT Top Off Charge Droop Threshold Conditioning Current ` Test Conditions VDD Maximum Dropout Voltage ` Symbol ≤ WWW . Microsemi .C OM Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C ≤ TA otherwise noted and the following test conditions: VDD = 5.0V. Page 3 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET SIMPLIFIED BLOCK DIAGRAM WWW . Microsemi .C OM PSW VID0 CHARGE/ DISCHARGE CONTROL VDD STAT 0.1 VIN BAT CHARGE TERMINATION CONTROL CUS CTP USB LIMIT CONTROL VID1 VM CONSTANT VOLTAGE CONTROL CMP TEMPERATURE CONTROL CCP CONSTANT CURRENT CONTROL GND BLOCK DIAGRAM Figure 1 – Simplified Block Diagram Copyright © 2000 Rev. 1.3, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 4 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION CIRCUITS WWW . Microsemi .C OM LX2201 C O N TR O L FLO W D IAG R AM R ETUR N TO STAR T IF VIN > VB AT O R VIDX C H AN G E STATE. START V DD > V B AT NO YES VID 0 = 1 NO YE S NO VID0 = 1 YES NO V B AT >60% CO N DITIO N CHARG E M O DE YES DISCHARG E M O DE YE S CO NSTANT C URRENT CH AR G E M O D E I U SB D ETER M IN ED BY TH E S TATE O F VID 1. TEM P < TEM P < 140 NO SW ITCH O FF NO VID 0 = 1 REDUCE CHARG E CU RRENT 140 I IN < I US B NO REDUCE CH AR G E C URRENT YE S NO REDUCE CHARG E C URRENT YE S YE S I IN NO < I US B NO REDUCE CH AR G E C URRENT YE S NO I BAT <I M IN V B AT > V C V YE S VO LTAG E M O NITO RIN G M O DE (STATE). YE S CO NSTANT VO LTAG E CH AR G E M O D E APPLICATIONS V B AT <97% NO Y ES RETU RN TO THE TO P O F THE CH AR T. Figure 2 – Control Flow Diagram Copyright © 2000 Rev. 1.3, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 5 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION SCHEMATICS WWW . Microsemi .C OM USB Lo / Hi NC PSW VID1 VID0 VM To System Power Bus VDD BAT VDD BAT LX2201 VDD AC/DC Adapter 10uF BAT VDD BAT VIN CMP 0.1uF CCP STAT CTP CUS GND USB POWER 2.5k 150k 75k 10uF Figure 3 – AC Adapter and USB Supply (Charge and Discharge Modes) APPLICATION SCHEMATICS (CONTINUED) Off / On NC PSW VID1 VID0 VM To System Power Bus VDD BAT VDD BAT LX2201 VDD AC/DC Adapter 10uF BAT BAT VIN CMP APPLICATIONS VDD 0.1uF 10uF CCP STAT CTP CUS TO BAT GND 100K TO VDD 499k 576k DMMT3906W 499k 499k 2.5k 150k 75k Figure 4 – AC Adapter with charging voltage headroom regulation (for use with a current limited power supply) Copyright © 2000 Rev. 1.3, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 6 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET Termination Current (mA) 100.5 100 99.5 99 98.5 98 -55 -35 -15 5 25 45 65 52 50 48 46 44 42 40 -55 85 -35 Am bient Tem perature (°C) Chart 1 – Charging Current Accuracy over Temperature 25 45 65 85 USB Low Current (mA) 92.9 463 462.8 462.6 462.4 462.2 462 92.8 92.7 92.6 92.5 92.4 92.3 92.2 92.1 92 4 4 .5 5 5 .5 6 6 .5 4 4 .5 VIN Voltage (V) 5 5 .5 6 6 .5 VIN Voltage (V) Chart 3 – USB High Current over VIN Voltage Chart 4 – USB Low Current over VIN Voltage 103 102.5 Stat Voltage Battery Voltage 102 101.5 101 100.5 100 5 1000 4 800 3 600 2 400 1 200 CHARTS Charging Current Accuracy (%) 5 Chart 2 – Termination Current over Temperature 463.2 USB High Current (mA) -15 Am bient Tem perature (°C) Battery Current (mA) Charging Current Accuracy (%) 101 WWW . Microsemi .C OM 54 101.5 99.5 99 4 4 .5 5 5 .5 6 6 .5 0 50 100 150 200 250 Time (minutes) VDD Voltage (V) Chart 6 – Battery Current & Voltage vs. Time Chart 5 – Charging Current over VDD Voltage Copyright © 2000 Rev. 1.3, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 7 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET THEORY OF OPERATION TOP OFF CHARGE MODE The LX2201 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 LX2201 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 LX2201 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 LX2201 enters a Voltage Monitoring mode. In this mode the LX2201 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). USB CHARGE MODE The LX2201 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 LX2201 senses the current flowing from the VIN terminal to the VDD terminal; then it limits the VIN current by reducing the current flowing from VDD to VBAT. Note: the USB Charge Limit circuit does not limit the input current and only scales the charging current. WWW . Microsemi .C OM GENERAL DESCRIPTION DISCHARGE MODE In discharge mode, VID0 is, indicate discharge mode enable. The system load is connected to VDD. The input power is connected to VDD through an internal diode. When the input power is removed, the battery current flows from VBAT to VDD. The circuit of Figure 3 shows the LX2201 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 LX2201 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 CHARGE TERMINATION MODE Copyright © 2000 Rev. 1.3, 2006-02-09 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 LX2201 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. Page 8 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION NOTE USB COMPLIANCE When using input power supplies that are current limited or have high source impedance, the battery charging current and/or load current can pull the VDD pin down very close to the battery terminal voltage. This may cause the LX2201 to enter an indeterminate state where it switches between charge and discharge modes. To prevent this, the PNP differential amplifier circuit of figure 4 can be added; this circuit adds an additional control loop that regulates the charger headroom to 300mV by scaling back the battery charging current. The internal power switch within the LX2201 requires the power supply have a minimal level of strength to switch from discharge mode to charge mode. If the power source is severely current limited, the LX2201 may not open the discharge switch. In this case, a small amount of current will be allowed to flow into the battery unregulated. If left in this state indefinitely, the current will eventually raise the battery terminal voltage to the point where the batteries internal protection circuitry will open the circuit. Typically, the LX2201 requires a minimum of 80mA in USB mode and 200mA using the VDD input to force the switchover to charge mode. Alternatively, if weak power sources are used, the switchover from discharge to charge mode can be forced by momentarily setting VID0 and VID1 to a low state, which will open the discharge switch allowing the VDD voltage to rise so the LX2201 can enter charge mode. 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 LX2201 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 to the battery and the LX2201 will prevent the load + battery from drawing more power than is allowed for USB compliance. A better approach that provides battery isolation may be used; in this approach, the op amp circuit provides a current limiter that prevents the system from exceeding the USB power limits. The battery is only discharged if the AC adapter or USB inputs are removed or current limited. WWW . Microsemi .C OM CURRENT LIMITED POWER SUPPLIES LAYOUT GUIDELINES • It is important when laying out the LX2201 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 LX2201 package to the ground plane of the circuit board to maximize the heat dissipation. APPLICATIONS Copyright © 2000 Rev. 1.3, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 9 Not Recommended for New Design: See the LX2202 LX2201 ® TM USB Li-Ion Battery Charger 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 © 2000 Rev. 1.3, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 10 Not Recommended for New Design: See the LX2202 LX2201 TM ® USB Li-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 © 2000 Rev. 1.3, 2006-02-09 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 11