MAX8845Z/MAX8845Y/MAX8845X/MAX8845W 19-4340 Rev 1 9/09 28V Linear Li+ Battery Chargers with Battery Detection and Overvoltage Protected Output General Description Features The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W are CCCV, Thermally Regulated Linear 1-Cell Li+ intelligent, stand-alone constant-current, constant-volt- Battery Charger age (CCCV), thermally regulated linear chargers No External MOSFET, Reverse Blocking Diode, or designed for charging a single-cell lithium-ion (Li+) bat- tery. The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W Current-Sense Resistor integrate a current-sense circuit, MOSFET pass element, Programmable Fast-Charge Currents (1A max) RMS thermal-regulation circuitry, and eliminate the external reverse-blocking Schottky diode to create the simplest Programmable Top-Off Current Threshold (MIN) and smallest charging solutions for handheld equipment. Input Overvoltage Protected 4.7V Output The ICs control the charging sequence from the pre- (MAX8845Z/MAX8845Y/MAX8845W) or 4.85V qualification state through constant current fast-charge, (MAX8845X) (SAFEOUT) top-off charge, and full-charge indication. Proprietary Proprietary Die Temperature Regulation Control thermal-regulation circuitry limits the die temperature during fast-charging or when the ICs are exposed to (+115C) high ambient temperatures, allowing maximum charg- 4.25V (4.4V for MAX8845W only) to 28V Input ing current without damaging the ICs. Voltage Range with Input Overvoltage Protection The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W Above +7.5V (+8.0V for MAX8845X only) achieve high flexibility by providing adjustable fast- Low-Dropout Voltage (300mV at 500mA) charge currents (SETI) and an adjustable top-off cur- rent threshold (MIN) through external resistors. The Input Power-Source Detection Output (POK), MAX8845Z/MAX8845Y/MAX8845X/MAX8845W feature Charge Status Output (CHG), Charge-Enable Input a booting assistant circuit that distinguishes input (EN) sources and battery connection and provides an enable signal (ABOMAX8845Z and ABO Output for Autobooting (ABOMAX8845Z, MAX8845Y/MAX8845X/MAX8845W) for system booting. ABOMAX8845Y/MAX8845X/MAX8845W) The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W also Tiny, 3mm x 3mm 12-Pin Thin QFN Package, integrate an overvoltage-protected output (SAFEOUT) for 0.8mm Height (max) low voltage-rated USB or charger inputs in system, and a battery-pack detection circuit (DETBAT) that disables the charger when the battery pack is absent. Other features Ordering Information include an active-low control input (EN), an active-low input power source detection output (POK), and a fully ABO charged top-off threshold detection output (CHG). TOP PART PIN-PACKAGE ACTIVE The MAX8845Z/MAX8845Y/MAX8845X/MAX8845W MARK STATE accept an input supply range from 4.25V (4.4V for MAX8845W only) to 28V, but disable charging if the MAX8845ZETC+ 12 Thin QFN-EP* ABL Active high supply voltage exceeds +7.5V (+8.0V for MAX8845X MAX8845YETC+ 12 Thin QFN-EP* ABM Active low only) to protect against unqualified or faulty AC MAX8845XETC+ 12 Thin QFN-EP* ABQ Active low adapters. The ICs operate over the extended tempera- MAX8845WETC+ 12 Thin QFN-EP* ABR Active low ture range (-40C to +85C) and are available in a com- pact 12-pin, thermally enhanced thin QFN, 3mm x 3mm Note: All devices are specified over the -40C to +85C oper- package (0.8mm max height). ating temperature range. Applications +Denotes a lead(Pb)-free/RoHS-compliant package. Cellular and Cordless Phones *EP = Exposed pad. Smart Phones and PDAs Digital Still Cameras MP3 Players Typical Operating Circuit and Pin Configurations appear at end of data sheet. USB Appliances Charging Cradles and Docks Bluetooth is a registered trademark of Bluetooth SIG. Bluetooth Equipment Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE28V Linear Li+ Battery Chargers with Battery Detection and Overvoltage Protected Output ABSOLUTE MAXIMUM RATINGS IN to GND...............................................................-0.3V to +30V BATT Short-Circuit Duration.......................................Continuous ABI, BATT, EN, POK, ABO, ABO, CHG, DETBAT, SETI, MIN, Operating Temperature Range ...........................-40C to +85C SAFEOUT to GND ................................................-0.3V to +6V Junction Temperature......................................................+150C IN to BATT Continuous Current .........................................1A Storage Temperature Range .............................-65C to +150C RMS Continuous Power Dissipation (T = +70C) Lead Temperature (soldering, 10s) .................................+300C A 12-Thin QFN (derate 14.7mW/C above +70C) (multilayer PCB) ......................................................1176.5mW 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 (V = 5V, V = 4V, R = 1M to BATT, EN = unconnected, R = 2.8k to GND, V = 0, C = 2.2F, T = -40C to IN BATT POK SETI DETBAT BATT A +85C, unless otherwise noted. Typical values are at T = +25C.) (Note 1) A PARAMETER CONDITIONS MIN TYP MAX UNITS Input Supply Voltage Range 0 28 V 4.25 7.00 Input Supply Operating Voltage Range V MAX8845W only 4.40 7.00 V rising, 100mV hysteresis (typ) 7.0 7.5 8.0 IN Overvoltage Lockout Trip Threshold V MAX8845X only 7.5 8.0 8.5 Constant current charging 0.22 0.50 I - I , I = 0 IN BATT BATT Constant current charging 1 I - I I = 500mA IN BATT, BATT Input Current mA IC disabled, V = 5V 0.20 0.50 EN V = 4V, IN T = +25C 0.02 A V = 4.2V (4.35V for BATT T = +85C 0.03 MAX8845W only) A BATT, CHG, POK Minimum BATT Bypass Capacitance 2.2 F V Prequalification Threshold Voltage V rising, 100mV hysteresis (typ) 2.3 2.5 2.7 V BATT BATT 4.175 4.200 4.225 I = 0 T = -40C to +85C BATT A 4.158 4.200 4.242 Battery Regulation Voltage V 4.324 4.350 4.376 MAX8845W only 4.306 4.350 4.394 Regulator Dropout Voltage (V - V)V = 4.1V, I = 425mA 260 mV IN BATT BATT BATT V = 0 to 4V, IN 510 V = 4.2V (4.35V for MAX8845W only) BATT Input Current BATT A IC disabled 3 Current-Sense Amplifier Gain (I to I )I = 500mA 1016 A/A BATT SETI BATT T = 0C to +85C 460 500 540 A V = 3.5V, BATT R = 2.8k SETI T = -40C to +85C 425 500 575 A Fast-Charge Current mA V = 3.5V, BATT T = 0C to +85C 85 100 115 A R = 14k SETI I falling, battery is charged BATT CHG Top-Off Threshold 106 mA R = 1.75k MIN 2 MAX8845Z/MAX8845Y/MAX8845X/MAX8845W