MAX8568A/MAX8568B 19-3450 Rev 1 5/05 Complete Backup-Management ICs for Lithium and NiMH Batteries General Description Features The MAX8568A/MAX8568B backup-battery-management Automatically Manage All Backup Switchover ICs are complete charging and backup switchover con- Functions trol solutions for PDAs, Smart Phones, and other smart Charge Both NiMH and Rechargeable Lithium portable devices. They charge both NiMH and rechargeable lithium battery types and feature pro- Backup Batteries grammable charge current and termination voltage. On-Chip Battery Boost Converter for 1-Cell NiMH Separate optimized charge algorithms for both lithium Two Backup Output Voltages and NiMH cells are included on-chip. The MAX8568A/MAX8568B also manage backup Programmable Charge Current switchover from a primary power source. An accurate on- Programmable Charge Voltage Limit chip voltage detector monitors the main supply and backs up two system supplies (typically I/O and memory) Low 17A Operating Current in Backup Mode when main power falls. On-chip drivers switch external Eliminate Many Discrete Components MOSFETs to disconnect the main supply from the system loads so the backup source is not drained. Tiny 3mm x 3mm Thin QFN Package Low-voltage backup cells can be stepped up by an on- Ordering Information chip synchronous-rectified, low-quiescent-current boost converter. Additionally, a low-quiescent-current LDO gen- PIN- TOP erates a second backup voltage. The MAX8568A LDO is PART TEMP RANGE PACKAGE MARK preset to 2.5V while the MAX8568B LDO is preset to 1.8V. Both devices are supplied in 16-pin 3mm x 3mm thin 16 Thin QFN QFN packages rated for -40C to +85C operation. MAX8568AETE -40C to +85C 3mm x 3mm ACK (T1633-4) Applications PDAs and PDA Phones 16 Thin QFN MAX8568BETE -40C to +85C 3mm x 3mm ACL Smart Phones (T1633-4) DSCs and DVCs Palmtops and Wireless Handhelds Typical Operating Circuit Internet Appliances and Web-Books MAIN BATTERY 2.8V TO 5.5V REF IN Pin Configuration BACKUP BATTERY BK MAX8568A MAX8568B TOP VIEW TERMV 12 11 10 9 I/O OUT LX STRTV 3.3V, 50mA BKSU GND 13 8 OD2 IN I/O IN PGND GND STRTV 14 7 OD1 MAX8568A BKV INOK TERMV 15 MAX8568B 6 LDO OD1 CHGI MEM OUT REF 16 5 BKSU 1.8V OR 2.5V, 10mA LDO MEM IN 12 3 4 NI LI OD2 NI/LI THIN QFN Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE IN CHGI BK INOK PGND BKV LX NI/LIComplete Backup-Management ICs for Lithium and NiMH Batteries ABSOLUTE MAXIMUM RATINGS IN, BK, BKSU, OD1, OD2 to GND.........................-0.3V to +6.0V Continuous Power Dissipation (T = +70C) A BKV, LDO, NI/LI to GND.........................-0.3V to (V + 0.3V) 16-Pin 3mm x 3mm Thin QFN BKSU REF, CHGI, INOK, TERMV, STRTV to GND...-0.3V to (V + 0.3V) (derate 15.6mW/C above +70C).............................1250mW IN PGND to GND ......................................................-0.3V to + 0.3V Operating Temperature Range ...........................-40C to +85C LX Current ......................................................................0.9A Junction Temperature......................................................+150C RMS Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C 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 (Circuit of Figure 7, V = V = 3.6V, V = 1.4V, V = V = 3.3V, V = GND = PGND = 0V, V = V = 1.2V, IN INOK BK NI/LI BKSU BKV STRTV TERMV R5 = 250k , T = 0C to +85C, unless otherwise noted. Typical values are at T = +25C.) (Note 1) A A PARAMETER CONDITIONS MIN TYP MAX UNITS IN Voltage Range 2.8 5.5 V T = +25C 3 5 A Charger off, V = 1.5V INOK IN Operating Current T = +85C 3 A A Charger on, not including charge current 50 90 CHGI Current Limit R = 169k , V = 1.3V 8 10 12 mA CHGI BK CHGI Bias Voltage 600 mV CHGI Resistor Range V = 1.3V 50 1800 k BK V = 5.5V, V = 0V 4.116 4.2 4.284 IN NI/LI BK Charge Voltage Limit V = 3.8V, V = 0V, V = 1V 3.42 3.5 3.58 V IN NI/LI TERMV V = V = 3.6V 1.746 1.8 1.854 IN NI/LI T = +25C 0.01 0.5 A BK Reverse Leakage Current to IN V = 0V A IN T = +85C 0.1 A NiMH Mode BK High Threshold Voltage, V = 1.2V 1.37 1.4 1.43 V TERMV V BK(NIHI) NiMH Mode BK Low Threshold Voltage, V = 1.2V 1.17 1.2 1.23 V STRTV V BK(NILO) T = +25C 0.001 0.05 A TERMV Input Current V = 1.1V A TERMV T = +85C 0.01 A T = +25C 0.001 0.05 A STRTV Input Current V = 1.1V A STRTV T = +85C 0.01 A REF Output Voltage I = 1A 1.23 1.25 1.27 V REF REF Load Regulation I = 1A to 50A 2.5 10 mV REF REF Line Regulation V = 3V to 5.5V, I = 1A 1 7 mV IN REF V falling 2.38 2.43 2.48 INOK INOK Threshold Voltage V V rising 2.40 2.47 2.54 INOK T = +25C 0.005 0.1 A INOK Input Current V = 2V A INOK T = +85C 0.05 A NI/LI Logic-Level High V = 3.3V 1.8 V BKSU NI/LI Logic-Level Low V = 3.3V 0.4 V BKSU 2 MAX8568A/MAX8568B