19-4929; Rev 1; 4/10 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN Features The MAX8922L linear battery charger safely charges a single-cell lithium-ion (Li+) battery. Charging rate is optimized to accommodate the thermal characteristics of a given application. There is no need to reduce the maximum charge current at the worst-case charger power dissipation. Charging is optimized for a single Li+ cell using a control algorithm that includes low-battery precharging, voltage and current-limited fast charging, and top-off charging, while continuously monitoring for input overvoltage and device die-temperature conditions. The fast-charge current and top-off current thresholds are programmable by a simple single-pin serial interface. The charger status and valid input power are indicated by two open-drain outputs (CHG and POK). o Overvoltage-Protected 30VDC Rated Input (IN) The fast-charge current is defaulted to 400mA and programmable through the single-pin interface (EN/SET). The MAX8922L also can be programmable to GSM test mode through the single-pin interface. The MAX8922L is available in a tiny (3mm x 2mm x 0.8mm) 10-pin TDFN package. o Prequalification Charge Applications o Input Overvoltage-Protected Safe 4.94V LDO Output o 2.3A GSM RF Test Mode o No External FET, Blocking Diode, or Sense Resistor Required o Single-Pin Easy Programmable Fast-Charge and GSM Test Mode (EN/SET) o Resistor-Programmable Fast-Charge Current (SETI) o Resistor-Programmable Top-Off Current Threshold (MIN) o Power-OK Monitor Output (POK) o Charging-Status Output (CHG) o Die Temperature Regulation for Optimized Charge Rate o Tiny (3mm x 2mm x 0.8mm) 10-Pin TDFN Package Ordering Information GSM/EDGE/UMTS/CDMA Cell Phones Digital Cameras PDAs Portable Media Players and MP3 Players PART PIN-PACKAGE TOP MARK MAX8922LETB+T 10 TDFN-EP* AWN +Denotes a lead(Pb)-free and RoHS-compliant package. *EP = Exposed pad. Wireless Appliances Note: This device operates in the -40°C to +85°C extended operating temperature range. POK CHG TEST EN/SET TOP VIEW BAT Pin Configuration 10 9 8 7 6 Typical Operating Circuit USB/AC ADAPTER 4.45V TO 30V IN BAT SETI LDO RSETI MIN *EP RMIN 5 MIN 4 LDO 3 GND 2 SETI IN 1 SYSTEM SUPPLY MAX8922L MAX8922L CHG EN\SET EP GND TEST POK TDFN (3mm x 2mm x 0.8mm) *EP = EXPOSED PAD. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX8922L General Description MAX8922L 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN ABSOLUTE MAXIMUM RATINGS IN to GND ..............................................................-0.3V to +30V BAT, CHG, EN/SET, POK, SETI, MIN, LDO, TEST to GND ......................................-0.3V to +6V IN to BAT Continuous Current .......................................1ARMS Continuous Power Dissipation (TA = +70°C) 10-Pin (3mm x 2mm) TDFN (derate 14.9mW/°C above +70°C) ..........................1188.7mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature Range ............................-40°C to +150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Soldering Temperature (reflow) .......................................+260°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VIN = 5V, VBAT = 4V, VEN/SET = 0V, TA = -40°C to +85°C, typical values are at TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS IN Input Voltage Range 0 28 V Input Voltage Operating Range (Note 2) 4.45 7 V Input Undervoltage Threshold (UVLO) VIN rising, 500mV hysteresis (typ) 3.80 3.90 4.00 V Input Overvoltage Threshold (OVP) VIN rising, 200mV hysteresis (typ) 7.2 7.5 7.8 V IBAT = 0mA, charge mode 700 1300 VEN/SET = 5V, standby mode 250 440 VIN = VBAT, shutdown mode 200 Input Supply Current IN-to-BAT On-Resistance IN-to-BAT Comparator Threshold VIN = 4.15V, VBAT = 4V VIN rising Ω 0.35 120 VIN falling 250 µA 500 100 mV BAT TA = +25°C 4.179 4.2 4.221 TA = -40°C to +85°C 4.158 4.2 4.242 BAT Regulation Voltage IBAT = 100mA Battery Removal Detection Threshold VBAT rising 4.67 Hysteresis 0.2 Charging Current V V Default fast-charge current, VBAT = 3.5V 365 400 435 EN/SET = one pulse with low > 4ms, RSETI = 3kΩ, one-pulse mode, VBAT = 3.5V 460 500 540 EN/SET = two pulses with low > 4ms, VBAT = 3.5V 80 90 100 mA EN/SET = three pulses with low > 4ms, VBAT = 3.5V (Note 3) 2350 Soft-Start Time Ramp time to fast-charge current 250 µs BAT Precharge Threshold VBAT rising, 300mV hysteresis (typ) 2.5 V Precharge Current BAT Leakage Current 2 80 VIN = 0V, VBAT = 4.2V 1 _______________________________________________________________________________________ mA 5 µA 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN (VIN = 5V, VBAT = 4V, VEN/SET = 0V, TA = -40°C to +85°C, typical values are at TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER CONDITIONS MIN TYP MAX UNITS LDO Minimum LDO Bypass Capacitance LDO Regulated Output Voltage ILDO = 10mA, VIN = 5V 4.8 LDO Output-Current Limit 1 µF 4.94 V 100 mA EN/SET Logic Input Thresholds Rising 1.4 Falling 0.4 Program Lock Time V 4 ms 4 ms Shutdown Delay VIN = 5V, EN/SET from low to high tLOW (Note 4) 100 1400 tHIGH (Note 4) 100 1400 Pulldown Resistor 2 µs MΩ POK, CHG Logic Output Voltage, Low IPOK, = ICHG = 5mA Logic Output Current, High VPOK = VCHG = 5.5V, VIN = 0V 0.05 0.2 TA = +25°C 0.001 1 TA = +85°C 0.01 V µA CHG IBAT falling, battery is charged Top-Off Threshold Detection Delay Default top-off threshold, hysteresis (typ) = 80mA 60 80 100 EN/SET = one pulse, RMIN = 1.875kΩ, hysteresis (typ) = 130mA 60 80 100 EN/SET = two pulses, hysteresis (typ) = 22mA 50 60 70 2 4 6 IBAT falls below top-off threshold mA ms THERMAL LOOP Thermal-Limit Temperature Junction temperature when the charge current is reduced, TJ rising +105 °C Thermal-Limit Gain Reduction of IBAT for increase of TJ, default mode -28 mA/°C Note 1: Limits are 100% production tested at TA = +25°C. Limits over the operating temperature range are guaranteed by design and characterization. Note 2: Guaranteed by undervoltage- and overvoltage-threshold testing. If VBAT = 4.2V, VIN needs to be > 4.2V + 250mV (typ) to start normal operation. After the MAX8922L turns on, it can operate until VBAT + 100mV (typ). For complete charging, the input voltage must be > 4.45V. See the Input Sources section. Note 3: Used for factory GSM RF calibration. 217Hz, 12.5% current pulse, TA = +25°C. Not for continuous charge current. Note 4: Not tested. Design guidance only. _______________________________________________________________________________________ 3 MAX8922L ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VIN = 5V, VEN/SET = 0V. VBAT = 4V, MAX8922L Evaluation Kit. TA = +25°C, unless otherwise noted.) DISABLED SUPPLY CURRENT vs. SUPPLY VOLTAGE 0.7 0.6 0.5 0.4 0.3 0.2 MAX8922 toc02 600 0.8 500mA SETI MODE 500 CHARGE CURRENT (mA) 0.8 0.9 STANDBY SUPPLY CURRENT (mA) 0.9 SUPPLY CURRENT (mA) 1.0 MAX8922 toc01 1.0 CHARGE CURRENT vs. BATTERY VOLTAGE MAX8922 toc03 SUPPLY CURRENT vs. SUPPLY VOLTAGE 0.7 0.6 0.5 0.4 0.3 0.2 400mA PRESET 400 300 200 90mA PRESET 100 0.1 0.1 0 0 0 1 2 3 4 5 6 0 0 7 1 2 3 4 5 6 7 0 1 2 3 4 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) BATTERY VOLTAGE (V) CHARGE CURRENT vs. SUPPLY VOLTAGE CHARGE CURRENT WITH ONE EN/SET PULSE CHARGE CURRENT WITH TWO EN/SET PULSES 450 400 MAX8922 toc04 400mA DEFAULT VBAT = 4V 5V/div 5V/div 0 VEN/SET 0 VEN/SET 350 5 MAX8922 toc06 MAX8922 toc05 500 CHARGE CURRENT (mA) 300 500mA 250 400mA 400mA 200 150 100 100mA/div 100mA/div 50 IBAT 0 0 3 6 9 IBAT 0 12 15 18 21 24 27 30 0 1ms/div 1ms/div SUPPLY VOLTAGE (V) CHARGE CURRENT vs. INPUT VOLTAGE HEADROOM GSM TRANSIENT RESPONSE MAX8922 toc07 700 200mv/div AC-COUPLED VBAT 1A/div IBAT MAX8922 toc08 800 NO BATTERY CBAT = 68µF 0A CHARGE CURRENT (mA) MAX8922L 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN 600 500 400 300 200 100 IFAST-CHARGE = 677mA 0 1ms/div 0 50 100 150 200 VIN - VBAT (mV) 4 _______________________________________________________________________________________ 250 300 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN 0.4 0.2 0 -0.2 -0.4 -0.6 VIN = 5V NO BATTERY -0.8 400 300 200 400mA PRESET VIN = 5V VBAT = 4V 100 -40 -15 10 35 60 AMBIENT TEMPERATURE (°C) 85 MAX8922 toc11 800 700 600 500 400 300 RSETI = 1.5kI VIN = 5V VBAT = 4V 200 100 0 0 -1.0 900 CHARGE CURRENT (mA) 500 CHARGE CURRENT (mA) 0.6 1000 MAX8922 toc10 0.8 VBAT REGULATION ACCURACY (%) 600 MAX8922 toc09 1.0 CHARGE CURRENT vs. AMBIENT TEMPERATURE (1A CHARGE) CHARGE CURRENT vs. AMBIENT TEMPERATURE BAT REGULATION VOLTAGE ACCURACY vs. AMBIENT TEMPERATURE -40 -15 10 35 60 85 -40 -15 AMBIENT TEMPERATURE (°C) 10 35 60 85 AMBIENT TEMPERATURE (°C) Pin Description PIN NAME 1 IN FUNCTION DC Input Supply. Connect IN to VIN > 4V and (VIN - VBAT) ≥ 250mV up to a 7V charging source. Bypass IN to GND with a 1µF or larger ceramic capacitor. Charge-Current Program and Fast-Charge Current Monitor. Output current from SETI is 1000µA per ampere of battery-charging current. Set the charging current by connecting a resistor (RSETI in Figure 1) from SETI to GND. IFAST-CHARGE = 1500V/RSETI. Connect to GND if pulse 1 mode (external SETI) is not used. Ground 2 SETI 3 GND 4 LDO 4.94V Regulated LDO Output with Input Overvoltage Protection. Bypass LDO to GND with a 1µF or larger ceramic capacitor. LDO can be used to supply low-voltage-rated USB systems. 5 MIN Top-Off Current Threshold Programmable Input. IMIN = 150V/RMIN. Connect to GND if pulse 1 mode (external SETI) is not used. 6 EN/SET 7 TEST Factory Test Input. Connect to GND. 8 CHG Charging-Status Output. CHG is internally pulled low when the charger is in prequalification or fastcharge mode. CHG is high impedance when the charger is in top-off or disabled. 9 POK Input Power-OK Monitor. POK is an open-drain output that is internally pulled low when VIN is greater than VUVLO and lower than VOVP and VIN > VBAT + 250mV. POK is high impedance when VIN is less than VUVLO or greater than VOVP or VIN < VBAT + 100mV. 10 BAT Battery Connection. The IC delivers charging current and monitors battery voltage using BAT. Bypass BAT to GND with a 2.2µF or larger ceramic capacitor. BAT is high impedance when the IC is disabled. — EP Active-Low Enable Input. EN/SET is used for programming fast-charge current and GSM test mode. For detailed descriptions, see the Charger-Enable and Program Input (EN/SET) section. Exposed Pad. Connect to the GND plane for increased thermal dissipation. _______________________________________________________________________________________ 5 MAX8922L Typical Operating Characteristics (continued) (VIN = 5V, VEN/SET = 0V. VBAT = 4V, MAX8922L Evaluation Kit. TA = +25°C, unless otherwise noted.) MAX8922L 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN 4.45V TO 30V MAX8922 IN BAT Li+ LDO Tj(DIE) CC/CV REGULATOR LDO CONTROL +105°C 3.9V TOP-OFF SWITCH BAT 7.5V FAST-CHARGE SWITCH MIN CHARGE AND LOGIC CONTROL RSETI EN/SET BAT PRECHARGE POK CHG 2.5V GND EP TEST Figure 1. MAX8922L Functional Diagram 6 RMIN SETI _______________________________________________________________________________________ 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN Soft-Start The MAX8922L is designed to charge a single-cell Li+ battery from a DC source voltage between 4.45V and 7V, while VIN can withstand up to 30V. The fast-charge current and top-off current thresholds are programmable with EN/SET, SETI, and MIN. Charger-Enable and Program Input (EN/SET) EN/SET is an active-low logic input that enables the charger. Drive EN/SET high longer than 4ms to disable the charger-control circuitry. If EN/SET is left unconnected, an internal 2MΩ pulldown resistor enables 400mA fast-charge current by default. The pulse programming scheme shown in Table 1 and Figure 3 is used to program the charge current and GSM test mode. There are four different fast-charge current states. Default fast-charge current state is 400mA mode. More than three pulses are interpreted to 90mA mode. After programming is locked, the MAX8922L ignores pulses until the IC is disabled/enabled or input power is cycled. Each fast-charge state is locked after a 4ms logic-low is asserted on EN/SET, followed by programming pulses. However, during default mode, if EN/SET does not receive any pulses, the charger stays in default mode unlocked indefinitely. Debounce Timer To prevent the MAX8922L from charging the battery momentarily upon IN power-up with EN/SET held low, a 2ms (typ) debounce timer delays the charging loop upon power-up. If EN/SET is logic-low or unconnected (pulled down by an internal pulldown resistor) during IN power-up, the charger starts charging the battery 2ms after VUVLO < VIN < VOVP and VBAT + 250mV < VIN. If EN/SET is logic-high during IN power-up, the charger does not charge the battery. To prevent input transients, the rate of change of the charge current is limited when the charger is turned on or changes its current compliance. It takes approximately 250µs (typ) (tSOFTSTART) for the charger to go from 0mA to the maximum fast-charge current. Thermal-Limit Control The MAX8922L features a thermal limit that reduces the charge current when the die temperature exceeds +105°C. As the temperature increases above +105°C, the IC decreases the charge current by 28mA/°C. Charge-Indicator Output (CHG) CHG is an open-drain output that indicates charger status. CHG goes low during charging in prequalification or fast-charge mode. The CHG internal open-drain MOSFET turns off when the charge current reaches the top-off threshold. The CHG status is latched after the top-off threshold is reached. The latch can be reset as follows: • Disable and re-enable the MAX8922L. • Input power is cycled. • Battery-charge current increases greater than the top-off threshold + hysteresis. When the MAX8922L is used in conjunction with a microprocessor, connect a pullup resistor between CHG and the logic I/O voltage to indicate charge status to the µP. Alternatively, CHG can sink 5mA or more for an LED charge indicator. Table 1. Charge-Current Pulse Settings CHARGE CURRENT IBAT (mA) DEFAULT 400mA NUMBER OF PULSES + > 4ms LOGIG-LOW FAST-CHARGE CURRENT SETTING One SETI, resistor programmable Two 90mA Three 2.3A (GSM test) Four and more 90mA _______________________________________________________________________________________ 7 MAX8922L Detailed Description MAX8922L 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN CHARGER LOOP DEFAULT IS OFF; IF EN/SET = LOW UPON POK. CHARGER LOOP ACTIVATES AFTER 4ms POR DEBOUNCE ASYNCHRONOUS FROM ANYWHERE tEN/SET = HIGH > 4ms STANDBY MODE CHARGER = OFF POK = LOW CHG = HIGH IMPEDANCE VUVLO < VIN < VOVP AND VIN > VBAT + 250mV VIN < VUVLO OR VIN > VOVP OR VBAT + 100mV > VIN EN/SET = LOW PREQUALIFICATION PRECHARGE CURRENT POK = LOW CHG = LOW VBAT < 2.5V VBAT < 2.2V SHUTDOWN CHARGER = OFF POK = HIGH IMPEDANCE CHG = HIGH IMPEDANCE PULSE 3 MODE DOES NOT HAVE PRECHARGE STATE ASYNCHRONOUS FROM ANYWHERE VIN < VUVLO OR VIN > VOVP OR VBAT + 100mV > VIN POK = (VOVP > VIN > VUVLO) AND (VIN - VBAT) > 250mV VBAT > 2.5V FAST CHARGE (PULSE PROGRAMMABLE) 100% CHARGER CURRENT POK = LOW CHG = LOW ICHG > ITOP-OFF + HYSTERESIS ICHG < ITOP-OFF FULL BATTERY VBAT = 4.2V POK = LOW CHG = HIGH IMPEDANCE FULL BATTERY CONTINUES TO REGULATE VBAT TO 4.2V Figure 2. Charger State Diagram Power-OK Indicator (POK) The MAX8922L contains an open-drain POK output that goes low when VIN is greater than VUVLO and lower than VOVP and VIN exceeds the battery voltage by 250mV. Once charging has started, charging is sustained with 8 inputs as low as 3.5V, as long as the input voltage remains above the battery voltage by at least 100mV. POK status should be maintained even though the charger is disabled by EN/SET. When VIN > VOVP, POK is high impedance. _______________________________________________________________________________________ 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN MAX8922L DC HIGH IMPEDANCE PULL LOW POK > 4ms 1 2 3 > 4ms EN tHIGH tLOW NO TIME LIMIT SETI MODE (1 PULSE + > 4ms LOW) tSOFTSTART 90mA MODE (2 PULSES + > 4ms LOW) 400mA SETTING (DEFAULT) GSM TEST MODE (3 PULSES + > 4ms LOW) IFAST OFF Figure 3. Charge-Current Programming LDO Output The LDO is preset to an output voltage of 4.94V and a 100mA current limit (typ). The LDO is powered from IN and has input overvoltage protection. The LDO is on if a valid input is present (VUVLO < VIN < VOVP). Bypass LDO to GND with a 1µF or larger ceramic capacitor. The LDO can be used to supply low-voltagerated USB systems. Applications Information Fast-Charge Current Settings In pulse 1 mode, the maximum charging current is programmed by an external resistor connected from SETI to GND (RSETI). Calculate RSETI as follows: RSETI = 1500V/IFAST-CHARGE where I FAST-CHARGE is in amperes and R SETI is in ohms. SETI can be used to monitor the fast-charge current level in the one-pulse mode (RSETI mode). The output current from SETI is 1000µA per ampere of charging current. The output voltage at SETI is proportional to the charging current (ICHARGE) when SETI mode is used for the fast-charge current: VSETI = ICHARGE x RSETI/1000 The voltage at ISET is nominally 1.5V at the selected fast-charge current and decreases with charging current as the cell becomes fully charged or as the thermal-regulation circuitry activates. Top-Off Current Settings The top-off charging current is programmed by an external resistor connected from MIN to GND (RMIN) in the one-pulse mode (RSETI mode). Calculate RMIN as follows: RMIN = 150V/IMIN where IMIN is in amperes and RMIN is in ohms. Capacitor Selection Connect a 2.2µF ceramic capacitor from BAT to GND for proper stability. Connect a 1µF ceramic capacitor from IN to GND. Use a larger input bypass capacitor for high charging currents to reduce supply noise. All capacitors should be X5R dielectric or better. Be aware that some capacitors have large-voltage coefficients, and should be avoided. _______________________________________________________________________________________ 9 MAX8922L 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN AC ADAPTER IN BAT 4.2V Li+ C2 2.2µF C1 1µF LDO MIN SYSTEM VBUS C3 1µF R1 1.87kΩ VI/O MAX8922L SETI R2 3kΩ EP POK GPIO CHG GPIO EN/SET GPIO GND TEST Figure 4. AC Adapter Charger Application Thermal Considerations Recommended PCB Layout and Routing The MAX8922L is in a thermally enhanced TDFN package with an exposed pad. Connect the exposed pad of the package to a large copper ground plane to provide a thermal contact between the device and the circuit board. The exposed pad transfers heat away from the device, allowing the IC to charge the battery with maximum current, while minimizing the increase in die temperature. Place all bypass capacitors for IN and BAT as close as possible to the IC. Connect the battery to BAT as close as possible to the IC to provide accurate battery voltage sensing. Provide a large copper ground plane to allow the exposed pad to sink heat away from the device. Make all high-current traces short and wide to minimize voltage drops. A sample layout is available in the MAX8922L Evaluation Kit to speed designs. Input Sources The MAX8922L operates from well-regulated DC sources. The charger input voltage range is 4.45V to 7V. The device survives input voltages up to 30V without damage to the IC. If the input voltage is greater than 7.5V (typ), the IC stops charging. An appropriate power supply must provide at least 4.2V plus the voltage drop across the internal-pass transistor when sourcing the desired peak charging current. VIN(MIN) > 4.2V + IFAST-CHARGE(MAX) x RON where RON is the input-to-BAT resistance. Failure to meet this requirement results in an incomplete charge or increased charge time. 10 Typical Application Circuits AC Adapter Charge Figure 4 shows the MAX8922L as a Li+ battery charger with an AC adapter. The MAX8922L detects the presence of an input supply resulting in POK pulled low. Once POK is pulled low, the MAX8922L begins charging the battery when EN/SET is low or unconnected. The system can program the charge current by EN/SET pulses. By monitoring CHG, the system can detect the top-off threshold and terminate the charge through EN/SET. The MAX8922L also provides an overvoltageprotected 4.94V LDO output to a low-voltage-rated USB system input. ______________________________________________________________________________________ 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN IN MAX8922L USB CABLE BAT C2 2.2µF C1 1µF LDO MIN SYSTEM VBUS C3 1µF R1 1.87kΩ 4.2V Li+ VI/O MAX8922L SETI R2 3kΩ EP POK GPIO CHG GPIO EN/SET GPIO GND TEST Figure 5. USB-Powered Li+ Battery-Charger Application USB Charge The universal serial bus (USB) provides a high-speed serial communications port as well as power for the remote device. The MAX8922L can be configured to charge a single Li+ battery at the highest current possible from the host port. Figure 5 shows the MAX8922L as a USB battery charger. The microprocessor enumerates the host to determine its current capability. The system can program the charge current to 90mA, I SETI , or 400mA by EN/SET pulses if the host port is capable. The MAX8922L also provides an overvoltage-protected 4.94V LDO output to a low-voltage-rated USB system input. GSM Test Mode Figure 6 shows the MAX8922L in a GSM test mode. By sending three pulses to EN/SET, the MAX8922L goes into GSM test mode. GSM PA can pull up to 2.3A for 576µs once every 217Hz from the MAX8922L’s output. The configuration in Figure 6 is used for system development, testing, and calibrations in the production or design stage. ______________________________________________________________________________________ 11 MAX8922L 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN GSM PA USB CABLE IN BAT C2 68µF C1 1µF LDO MIN VBUS C3 1µF R1 1.87kΩ SYSTEM VI/O MAX8922L SETI R2 3kΩ EP POK GPIO CHG GPIO EN/SET GPIO GND TEST Figure 6. GSM Test Mode Chip Information PROCESS: BiCMOS 12 ______________________________________________________________________________________ 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN PACKAGE CODE DOCUMENT NO. 10 TDFN-EP T1032N+1 21-0429 TDFN.EPS PACKAGE TYPE ______________________________________________________________________________________ 13 MAX8922L Package Information For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. MAX8922L 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN Package Information (continued) For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. 14 ______________________________________________________________________________________ 30V Li+ Linear Battery Charger with GSM Test Mode in 3mm x 2mm TDFN REVISION NUMBER REVISION DATE 0 9/09 Initial release 1 4/10 Replaced 1-Wire references with single-pin, updated Absolute Maximum Ratings section, and added soldering temperature DESCRIPTION PAGES CHANGED — 1, 2 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 © 2010 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX8922L Revision History