LX2206

LX2206 TM ® Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET DESCRIPTION KEY FEATURES 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 APPLICATIONS 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. 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. W WW . Microsemi . C OM 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 Adapter or USB IN CMP Shutdown High/Low Charge Current Control Logic SD H/L HCP LCP Current Programming Battery GND STAT Full Power On DCOK LX2206 DCOK TMP BAT Battery Temperature Lockout Sensing LX2206 LX2206 PACKAGE ORDER INFO TA (°C) -40 to 85 LD Plastic MLPD 10-Pin RoHS Compliant / Pb-free LX2206ILD Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. 2206ILD-TR) Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 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) 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. PACKAGE PIN OUT W WW . Microsemi . C OM IN CMP STAT DCOK SD 1 2 3 4 5 10 9 8 7 6 BAT TMP HCP LCP H/L Connect Bottom PAD to GND LD PACKAGE PINOUT (Top View) RoHS / Pb-free 100% matte Tin Lead Finish THERMAL DATA LD Plastic Micro Leadframe Package 10-Pin 49°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. FUNCTIONAL PIN DESCRIPTION Name BAT CMP DCOK Description Battery – Connect to a single cell Lithium Ion Battery. Compensation – Connect the series combination of a 1k resistor and a 0.47µF capacitor from CMP to IN. 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. Ground – Connect to the system ground plane. Use sufficient via copper area to allow for thermal conduction from the IC to the GND plane. 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. 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 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. Shutdown – A logic high places the LX2206 in sleep mode; can also be used for USB suspend. 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. 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. GND HCP H/L IN LCP SD STAT P D PACKAGE DATA TMP Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 LX2206 TM ® Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET -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. ELECTRICAL CHARACTERISTICS W WW . Microsemi . C OM Parameter INPUT CIRCUITRY Input Voltage Battery Voltage Under Voltage Charging Lockout UVLO Hysteresis Input Supply Current BATTERY CHARGER Constant Voltage Charging Constant Voltage Charging HCP Bias Voltage LCP Bias Voltage Battery Charge Current Conditioning Current Conditioning Current Cond. Current Threshold Charge Termination Current Charge Termination Current Charge Termination Current Top Off Threshold Battery Drain Current LOGIC STAT Logic High Output STAT Logic Low Output Input Logic : SD, H/L Input Current : SD, H/L Output Logic : DCOK Symbol VIN VBAT VINUVLO IIN VCVL VCVL VHCP VLCP IBAT ICOND ICOND VCCT IBAT IBAT IBAT VTOT IBAT Test Conditions Min 4.35 LX2206 Typ Max 6 4.3 4 2 50 4.24 4.22 Units V V V mV mA µA V V V V mA mA mA mA mA V mA mA mA % VBAT VCVL Rising input VBAT = 3.2V VBAT = 4.2V; battery charged SHDN = High IBAT < 100mA IBAT < 100mA @ 25C IBAT > 100mA HCP = 12.1k H/L = Low VBAT < VCCT; HCP = 19.6k VBAT < VCCT; HCP = 110k HCP = 19.6k HCP = 110k HCP = 210k 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 Rising Threshold Falling Threshold Falling Threshold Rising Threshold 3.5 3.8 300 1 35 4.2 4.2 1.25 1.25 710 460 92 23 5.0 2.7 46 9 5 97 1 5 1 4.5 4.16 4.18 650 420 87 13 2.6 2.5 34 750 483 97 33 7.5 2.9 59 96 98 30 30 5 5 0.5 0.4 4 2 0.5 µA µA µA V V V µA V V V V V mV VDRV VDRV VLOG(IN) ILOG(IN) VLOG(OUT) 4.2 1.2 0 -2 3.1 2 0 BATTERY TEMPERATURE MONITOR Cold Temp Fault Threshold Hot Temp Fault Threshold TFB Disable Voltage VCOLD VHOT VDIS 0.75 x VIN 0.72 x VIN 0.28 x VIN 0.30 x VIN 100 150 E ELECTRICALS 75 Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 3 LX2206 TM ® Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET SIMPLIFIED BLOCK DIAGRAM W WW . Microsemi . C OM + SD ENABLE DCOK UVLO TMP CHARGE CONTROL STAT IN BAT CONSTANT VOLTAGE CONTROL CHARGE TERMINATION CONTROL TEMPERATURE CONTROL CONDITIONING THRESHOLD H/L COND. CURRENT LCP LOW CHARGING CURRENT HCP HIGH CHARGING CURRENT B D BLOCK DIAGRAM GND Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 W WW . Microsemi . C OM S TART RETURN TO START IF VIN > VBAT, UVLO, SD, CHANGE STATE. SD NO YES V IN YES > V BAT NO SLEEP UVLO NO YES VOLTAGE MONITORING M ODE (STATE). V BAT 60% YES NO CONDITION CHARGE MODE CONSTANT VOLTAGE CHARGE MODE CONSTANT CURRENT CHARGE M ODE I M AX D ETERM INED BY THE STATE OF H/L, R HC P , R LC P . TEM P < 1 30 YES NO REDUCE CHARGE CURRENT TEM P < 1 30 YES NO REDUCE CHARGE CURRENT I CC< I M AX YES NO REDUCE CHARGE CURRENT I CC < I M AX NO REDUCE CHARGE CURRENT APPLICATIONS APPLICATIONS NO I BAT V CV YES RETURN TO THE TOP OF THE CHART. Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 W WW . 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. USB 1k Suspend USB High/Low Control Logic 0.47uF IN CMP SD H/L HCP LCP GND STAT Charging 2.5k VCC 10k LX2206 DCOK TMP BAT DCOK 19.6k Current Programming 110k Battery Figure 2– Typical USB Application – 500mA or 100mA maximum charge currents with charge indicator. Adapter 1k Shutdown 0.47uF IN CMP SD H/L HCP LCP GND STAT Charging 2.5k VCC 10k A APPLICATIONS LX2206 DCOK TMP BAT DCOK 17.8k 63.4k Battery Figure 3 – Typical Low current application – 150mA charge current and 50mA termination current. Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 W WW . 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). 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. ADAPTER OR USB SELECTION 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. A APPLICATIONS Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 7 LX2206 TM ® Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET APPLICATION NOTE W WW . 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. 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: IHCP 1.25 1.25 = = = 11.4µA RHCP 110k Using the table below it can be seen that for a programming current value of 11.4µA, the corresponding maximum charge current is 92mA. 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) 100 80 60 40 20 0 0.00 50.00 100.00 150.00 IHCP (in uA) Charge Current vs IHCP (or ILCP) 1200 1000 800 600 400 200 0 0.00 The termination current is always roughly 10% of the maximum charge current set by the HCP resistor. Charge Current (in mA) A APPLICATIONS 50.00 100.00 150.00 IHCP (in uA) Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 W WW . 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. VTH RTH TMP RMIN RNTC 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 The values of R1 and R2 can be calculated as: R R1 = TH = 122K K R2 = R1 × RTH = 14,800K R1 − RTH 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. 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 ) In this case, it is not necessary to use R2, because the value is so large it is insignificant. In this case, R1 = RTH. ⎛K ⎞ R TH = ⎜ − 1⎟ × R T = 0C = 121K ⎝ 0.74 ⎠ A APPLICATIONS Where R at temperature is the sum of the thermistor plus RMIN. Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 W WW . Microsemi . C OM The final circuit for this example is: VIN 121k TMP 24.9k RNTC 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 Charge completed Input power removed STAT Low High Hi Z The TMP voltages with this circuit are: TEMP (°C) -20 0 25 60 80 RNTC 971k 327k 100k 24.9k 12.6k VTMP (% VIN) 89% 74% 51% 29% 24% A APPLICATIONS Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 CHARGING PROFILE Battery Charging USB High Level 4.25 4.20 4.15 B attery V o ltag e Vbat 4.10 4.05 4.00 3.95 3.90 0.0 60.0 Time in minutes 120.0 Ibat 0.50 0.45 CONDITIONING CURRENT W WW . Microsemi . C OM Conditioning Current vs IHCP 60 Conditioning Current (in mA) 50 40 30 20 10 0 0.00 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 B attery C u u ren t 50.00 IHCP (in uA) 100.00 150.00 FLOAT VOLTAGE TERMINATION CURRENT CHARTS CHARTS Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 W WW . Microsemi . C OM CHARTS CHARTS Copyright © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 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 W WW . Microsemi . C OM LD 10-Pin Plastic MLP Dual Exposed Pad D e L E E2 Top View b D2 Bottom View A A3 A1 Dim A A1 A3 b D D2 e E E2 L Note: 1. 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 M MECHANICALS 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 © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 13 LX2206 TM ® Dual Level Lithium Ion Battery Charger P RODUCTION D ATA S HEET NOTES W WW . Microsemi . C OM N 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 © 2005 Rev. 1.2, 2006-12-22 Microsemi Integrated Products Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 14