LX2205

LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET DESCRIPTION KEY FEATURES Single Cell Li-Ion Battery Charger Power Source Management Up to 1A Charging Current Integrated Power MOSFET USB Current Compliance 25µA Quiescent Current in Discharge Mode Taper Current Termination Protection features: USB Reverse Current Blocking Unsafe Battery Temp Lockout Internal IC Temperature Limiter USB Current Limiter The LX2205 is a complete single cell Lithium Ion or Lithium Polymer battery charger and power source manager. In addition to battery charging, power flow control is provided from up to three sources: a wall adapter, a standard USB power plug or the battery. The battery charge current and termination current are independently adjustable. The controller also includes status indicators which show when the controller is powered by an external adapter in addition to charge in progress, and charge completed. The USB input is current limited at two logically selectable levels (100mA and 500mA). When powered by a USB input, the battery is charged with the excess USB current that is not consumed by the system load. If the load exceeds the USB current limit, the battery will discharge to assist the USB power source to power the load. The controller can logically suspend the USB power to allow the system to operate from the battery without loading the USB. When a wall adapter is applied, it takes precedent over the USB power input and disables the USB input to prevent current flow from the adapter to the USB port. W WW . Microsemi . C OM o o o o APPLICATIONS IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com Patents Pending. Navigation Devices Portable USB Devices Multi-Media Player PDA Phones Digital Cameras PRODUCT HIGHLIGHT DC OK Wall Adapter USB Power Suspend High/Low Shutdown Adapter Present MDC USB SUSP UCL SHDN GND CCP CTP CMP SYS System Load LX2205 BAT CHG DONE CUS TFB Thermistor Charge/ Discharge Li-Ion LX2205 LX2205 PACKAGE ORDER INFO TA (°C) -40 to 85 LQ Plastic MLP 4 x 4mm 16 pin RoHS Compliant / Pb-free LX2205ILQ Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX2205ILQ-TR) Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET ABSOLUTE MAXIMUM RATINGS Supply Voltages (MDC, SYS, USB) ................................................................ -0.3V to 7V Battery Voltage (BAT) ..................................................................................... -0.3V to 6V All Other Pins .............................................................................................-0.3V to VSUPPLY USB Current .............................................................................................................600mA BAT Discharge Current ................................................................................................1.6A Operating Ambient Temperature Range (TA) ..............................................-45°C to 125°C Maximum Operating Junction Temperature (TJ) ....................................................... 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) Note: Exceeding these ratings could cause damage to the device. All voltages are with respect ground. Currents are positive into, negative out of specified terminal. to PACKAGE PIN OUT DC OK DONE CHG TFB W WW . Microsemi . C OM 16 15 14 13 12 11 10 9 8 C MP BAT SYS USB 1 2 3 4 5 Connect Bottom Pad to GND 6 7 CTP CCP GND CUS MDC SHDN LQ PACKAGE THERMAL DATA (Top View) RoHS / Pb-free 100% Matte Tin Pin Finish LQ Plastic 4 x 4mm 16-Pin 28°C/W* THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 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. See layout guidelines section for important details. FUNCTIONAL PIN DESCRIPTION Name BAT CCP Pin 2 11 14 1 12 9 13 15 10 Description Battery Connection - This pin is wired to the positive terminal of a single cell lithium ion/polymer battery. Charge Current Programming Pin - A resistor (RCCP) is connected between this pin and GND. The constant charging current is determined by the following relationship: RCCP = 50.648 x ICCL-1.0855 with RCCP in kΩ and ICCP in amps. Charge Indicator - This pin is a logic low level when the battery is being charged, provided VSYS is ≥ 4.4V. It is capable of driving the series combination of an LED and resistor that is powered from the SYS pin. Compensation – Connect a 0.1µF capacitor from CMP to SYS. Charge Termination Programming Pin – A resistor (RCTP) is connected between this pin and GND. The -1.0876 charge termination taper current is determined by the following relationship: RCTP =0.7354 x ITERM with RCTP in kΩ and ITERM in amps. USB Current Limit Programming Pin – A resistor (RCUS) is connected between this pin and GND. The high level USB charge current is determined by the following relationship: IUSB = 1050 / RCUS. Main DC Present – A low level on this logic output indicates that the Main DC power source (typically the wall adapter) is applied. Done Indicator - This pin is a logic low level when the battery charge cycle is complete. It is capable of driving the series combination of an LED and resistor that is powered from the SYS pin. Common Ground – Used as chip ground and as a reference for the battery return. CHG CMP CTP CUS DC OK SUSP UCL LX2205 LX2205 DONE GND Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET FUNCTIONAL PIN DESCRIPTION (CONTINUED) W WW . Microsemi . C OM Name MDC SHDN SUSP SYS TFB USB UCL Pin 5 6 7 3 16 4 8 Description Main DC Input – This input is a voltage monitoring input (and not a high current input). Its purpose is to determine the presence of the main DC input to provide lockout for the USB power input. Shutdown – Pulling this pin high will disable the entire device including the battery discharge path and place the device in a low power sleep mode. This pin has an internal pull-down. Suspend (USB) – Pulling this pin high will prevent current from being drawn from the USB input pin. The rest of the chip functions are unaffected. This pin has an internal pull-down. System Power Node – This pin provides power to user system. SYS voltage provided will range from the battery voltage to the wall adapter and/or USB voltage. Temperature Feedback – Charging is suspended when the TFB pin falls below 29% (typ) of VSYS or rises above 74% (typ) of VSYS. CHG and DONE pins remain in their prior state during a TFB event. Connecting the TFB pin to GND disables the TFB function. USB Power Input – USB compliant input. USB Current Limit – A high logic level will select the high USB current level determined by the programming of the CUS pin. A low logic level will select a level that is 20% of the high USB current level. This pin has an internal pull-down. LX2205 LX2205 Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 3 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating temperature -40ºC ≤ TA ≤ 85 ºC and the following test conditions: VMDC = VUSB = 5V, VSYS =Open, VSUSP = VSHDN = Low, VUCL = High, VBAT = 3.9V, RCCP = 49.9k, RCUS = 2.26k, RCTP = 20k Parameter MAIN CIRCUITRY Input Voltage Under Voltage Charging Lockout SYS UVLO Hysteresis USB UVLO SYS Input Supply Current VUSB(UVLO) ISYS VSUPPLY VSYS(UVLO) USB or SYS Rising input; VBAT = 3.2V Guaranteed by design Rising input; VBAT = 3.2V VBAT = VCVL; (battery charged), VSYS = 5.0V SHDN = High (Shutdown Mode), VSYS = 5.0V VBAT = VCVL; (battery charged), , VMDC = 0V USB Input Supply Current IUSB SUSP = High (Suspend Mode), , VMDC = 0V SHDN = High (Shutdown Mode), , VMDC = 0V VMDC = 0V, VUSB = 0V VBAT = VCVL; (battery charged) Battery Drain Current IBAT VMDC=0V; SUSP = High (Suspend Mode) SHDN = High (Shutdown Mode) VUSB = 0V; VMDC = 0V; Discharge with no load BATTERY CHARGER Constant Voltage Charge Voltage CTP Bias Voltage CCP Bias Voltage VCVL VCTP VCCP ICCL Max Battery Charge Current VSYS = 5.0V VMDC=0V IBAT VMDC=0V; ISYS = 200mA (out of pin) VMDC=0V; UCL = Low Conditioning Current Conditioning Current Threshold Voltage Charge Termination Current Top Off Charge Droop Threshold ICOND VCCT IBAT VDRP Expressed as a % of VCVL VBAT =2.5V, as a % of ICCL 2.5 2.55 40 96 0.85 IBAT > 100mA 4.16 4.2 1.30 1.25 0.98 465 261 92 5 2.7 50 97 7.5 2.9 60 98 1.10 4.24 V V V A mA mA mA % V mA % -1.5 0.5 25 0.5 25 4.25 4.35 3.55 3.7 140 4.30 1.5 25 2 25 25 -6 10 50 10 50 4.34 2.5 6 3.95 V V mV V mA µA mA µA µA µA µA µA µA µA Symbol Test Conditions Min LX2205 Typ Max W WW . Microsemi . C OM Units LX2205 LX2205 Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 4 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET ELECTRICAL CHARACTERISTICS (CONTINUED) Unless otherwise specified, the following specifications apply over the operating temperature -40ºC ≤ TA ≤ 85 ºC and the following test conditions: VMDC = VUSB = 5V, VSYS =Open, VSUSP = VSHDN = Low, VUCL = High, VBAT = 3.9V, RCCP = 49.9k, RCUS = 2.26k, RCTP = 20k W WW . Microsemi . C OM Parameter USB CURRENT LIMIT USB Low Current Limit USB High Current Limit Reverse Leakage Current CUS Bias Voltage LOGIC CHG , DONE Logic High Output CHG , DONE Logic Low Output Symbol Test Conditions Min 85 425 LX2205 Typ Max 93 463 2 2.5 100 500 10 Units IUSB IUSB ILEAK VCUS VOH VOL VLOG(IN) VMDC = 0V, UCL = Low VMDC = 0V VUSB = 0V mA mA µA V V VSYS = 5.0V, IOH = -25uA VSYS = 5.0V, IOL = 5mA Logic Hi, Logic Lo Logic Hi, VLOG = 2V Logic Lo, VLOG = 0V Logic Hi, 10K to 3.3V Logic Lo, ILOG = 100µA 4.0 4.5 0.4 V V Input Logic : UCL, SUSP, SHDN Input Logic Current : UCL, SUSP, SHDN Output Logic : DC OK THERMAL DIE PROTECTION Battery Charger Thermal Limiter 1.2 0.4 0 -2 3.2 0.4 2 0 4 2 ILOG(IN) µA VLOG(OUT) V TCTL 140 °C BI-DIRECTIONAL PASS ELEMENT CONTROL Discharge Switch On Resistance Charging Threshold Discharging Threshold Pass Element Switch Mode Delay Charging headroom Discharging headroom MDC INPUT DC OK Voltage Threshold RDS(ON) VCHG VDCH tsw IBAT = -1A VSYS – VBAT VBAT – VSYS Charge–To–Discharge or Discharge–To–Charge VSYS – VBAT, IBAT = 5mA VBAT – VSYS, IBAT = -20mA 275 40 40 2.5 80 80 mΩ mV mV µs mV mV VMDC VMDC(HYS) IMDC Rising 4.0 4.15 35 15 4.3 V mV Hysteresis MDC Input current 35 µA BATTERY TEMPERATURE MONITOR Cold Temp Fault Threshold VTFB(COLD) Rising Threshold ; as % of VSYS Falling Threshold; as % of VSYS Falling Threshold; as % of VSYS Rising Threshold; as % of VSYS 73 71 27 28 70 75 73 28.5 29.5 100 77 75 30 31 150 % % % % mV LX2205 LX2205 Hot Temp Fault Threshold TFB Disable Voltage Threshold VTFB(HOT) VTFB(DIS) Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 5 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET CHARGER CONTROL FLOW DIAGRAM START RETURN TO START IF VSYS > VBAT, UVLO, SUSP, OR SHDN CHANGE STATE. A TMP FAULT CAUSES THE CHARGER TO SUSPEND CHARGING. ONCE THE FAULT CLEARS, CHARGING RESUMES AT THE SAME POINT. W WW . Microsemi . C OM SHDN NO YES SWITCH OFF VOLTAGE MONITORING MODE (STATE). VSYS > VBAT YES NO DISCHARGE MODE VBAT60% YES NO CONDITION CHARGE MODE CONSTANT CURRENT CHARGE MODE IUCL DETERMINED BY THE STATE OF UCL. CONSTANT VOLTAGE CHARGE MODE TEMP < 140 YES NO TEMP < 140 YES NO ISYS< IMAX YES YES DC OK NO NO ISYS< IMAX REDUCE CHARGE CURRENT YES YES NO REDUCE CHARGE CURRENT DC OK NO LX2205 LX2205 IUSB< IUCL YES NO IUSB< IUCL YES NO NO NO VBAT> VCV YES IBAT VUSB VMDC > V DC OK _THRESHOLD LAYOUT GUIDELINES It is important when laying out the LX2205 to place 10µF ceramic capacitors as close to the SYS, USB and VBAT IC terminals as possible to filter switching transients. It is important to provide a low thermal impedance path from the thermal pad on the bottom of the LX2205 package to the ground plane of the circuit board to maximize heat dissipation. Generally this is accomplished by the use of multiple thermal vias. The compensation capacitor should be placed close to the CMP pin and connected with a short trace. CHARGE CURRENT PROGRAMMING The CCP, CTP, and CUS programming pins are used to program the constant charge current, termination current, and USB current, respectively. These pins utilize regulated output voltages that produce a program current across an external resistor to GND. The following tables are guidelines for selecting the proper resistor values: Constant Charge Current (in mA) RCCP 50 1270k 100 604k 200 294k 300 187k 400 137k 500 107k 600 88.7k 700 75.0k 800 63.4k 900 56.2k 1000 49.9k* * RCCP minimum value Termination Current (in mA) RCTP 5 237k 10 105k 20 51.1k 40 24.9k 60 15.8k 80 11.8k 100 9.09k 120 7.50k 140 6.34k 160 5.49k 180 4.75k 200 4.22k W WW . Microsemi . C OM The MDC input is a monitoring input only, it is not a high current input. When the voltage at SYS exceeds the UVLO level, (typically 3.7V), the charger portion of the circuit is activated. The DC OK output is pulled low when both of the following conditions are true: 1. 2. VMDC > V DC OK _THRESHOLD VSYS > VBAT Therefore when using a current limited wall adapter it is possible to charge the battery and not assert the DC OK output. 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% of full scale. This also protects the appliance from overheating by trying to drive the full charging current into a short circuited battery. Under Voltage Lockout – The charger remains inactive until the under voltage lockout threshold is exceeded at the SYS pin. Thermal Control Loop – The power dissipation of the charger is limited by reducing the charge current with a control loop to prevent the die temperature from exceeded approximately 140°C. Reverse Current Blocking – Current will not flow out of the USB pin. Shutdown Mode – If the SHDN pin is logic high, the charger enters a shutdown mode to prevent draining the battery. Battery Temperature Lockout – If an unsafe temperature is sensed by the TFB input window comparator, battery charging is suspended. LX2205 LX2205 Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 11 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET APPLICATION NOTE BATTERY TEMPERATURE MONITOR The LX2205 has an input to monitor the battery temperature during battery charging. The SYS voltage must be used to bias this circuitry. During the occurrence of a TMP fault, the charge cycle is suspended; however the status indicators state remains unchanged. A typical Lithium Ion battery should only be charged within a temperature range of 0°C to 60°C. For this calculation example, a Vishay NTHS0402N01N1003J thermistor was used. This thermistor has the value of 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 TMP thresholds. A fixed value resistor is added in series with the thermistor to prevent it from becoming too low 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 SYS pin. The values of R1 and R2 can be calculated as: W WW . Microsemi . C OM R1 = R2 = RTH = 88k K R1 × RTH = 958k R1 − RTH Actual standard 1% resistor values are: 953k and 88.7k. The final circuit for this example is: VSYS 88.7k TMP 12.4k 953k RNTC Using a value of RMIN that is ½ the thermistor high temperature trip resistance value works well; therefore, for this example, set the value of RMIN to: 12.4k = R MIN The TMP voltages with this circuit are: TEMP (°C) -20 0 25 60 80 RNTC 971k 327k 100k 24.9k 12.6k VTMP (% VSYS) 85% 74% 53% 29% 22% R = T =60°C . 2 This has the effect of adding a fixed 12.4k to the thermistor resistance values so it becomes 339kΩ at 0°C, 112kΩ at 25°C and 37.3kΩ at 60°C. The equations for RTH and VTH are, using Cold Temperature Fault Threshold average of 74% and the Hot Temperature Fault Threshold average of 29% of VSYS: LX2205 LX2205 0.29 × 0.74 × (RT =0°C − RT =60°C ) VTH = VSYS (0.29 × RT =0°C ) − (0.74 × RT =60°C ) = K = 0.916 ⎞ ⎛K RTH = ⎜ − 1⎟ × RT = 0°C = 80.6k ⎝ 0.74 ⎠ Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 12 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET TYPICAL CHARGING CURRENT VS BATTERY VOLTAGE 1.2 1 Charge Current (A) TYPICAL CHARGING CURRENT VS VSYS 1.2 1 Charge Current (A) 0.8 0.6 0.4 V BAT = 3.9V 0.2 0 4.2 4.6 5 SYS Voltage 5.4 5.8 W WW . Microsemi . C OM 0.8 0.6 0.4 0.2 0 3.2 3.4 3.6 3.8 4 4.2 Battery Voltage TYPICAL USB CURRENT LIMIT VS USB VOLTAGE 500 450 400 USB Current Limit (mA) 350 300 250 200 150 100 50 0 4 4.5 5 Input Voltage 5.5 6 TYPICAL VCVL DISTRIBUTION 1500 Typical Distribution Frequency USB Low USB Hi 1250 1000 750 500 250 0 4.16 4.17 4.18 4.19 4.20 4.21 4.22 4.23 4.24 VCVL VSY S = 5V TA = 25°C CHARGE TO DISCHARGE SWITCHOVER VSYS IBAT LX2205 LX2205 DC OK Copyright © 2007 Rev. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 13 LX2205 TM ® 1A Li-Ion Battery Charger with Power Source Management P RODUCTION D ATA S HEET PACKAGE DIMENSIONS LQ 16-Pin MLPQ Plastic (4x4mm EP / 114x114Cu Exposed Pad) W WW . Microsemi . C OM D b E2 L E D2 e A1 A3 A K Dim A A1 A3 b D E e D2 E2 K L Note: MILLIMETERS MIN MAX 0.80 1.00 0 0.05 0.18 0.30 0.23 0.38 4.00 BSC 4.00 BSC 0.65 BSC 2.55 2.80 2.55 2.80 0.20 0.30 0.50 INCHES MIN MAX 0.031 0.039 0 0.002 0.007 0.012 0.009 0.015 0.157 BSC 0.157 BSC 0.026 BSC 0.100 0.110 0.100 0.110 0.008 0.012 0.020 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. LX2205 LX2205 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. 1.0a, 2007-03-02 Microsemi Analog Mixed Signal Group 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 14