EVALUATION KIT AVAILABLE MAX1908/MAX8724/ MAX8765/MAX8765A Low-Cost Multichemistry Battery Chargers General Description Features The MAX1908/MAX8724/MAX8765/MAX8765A highly 0.5% Output Voltage Accuracy Using Internal integrated, multichemistry battery-charger control ICs Reference (0.4% for MAX8765A, 2-/3-Cell Only) simplify the construction of accurate and efficient charg- 4% Accurate Input Current Limiting ers. These devices use analog inputs to control charge current and voltage, and can be programmed by the host 5% Accurate Charge Current or hardwired. The MAX1908/MAX8724/MAX8765/ Analog Inputs Control Charge Current and MAX8765A achieve high efficiency using a buck topology Charge Voltage with synchronous rectification. The MAX1908/MAX8724/MAX8765/MAX8765A feature Outputs for Monitoring input current limiting. This feature reduces battery Current Drawn from AC Adapter charge current when the input current limit is reached Charging Current to avoid overloading the AC adapter when supplying AC Adapter Presence the load and the battery charger simultaneously. The Up to 17.6V Battery-Voltage Set Point MAX1908/MAX8724/MAX8765/MAX8765A provide out- puts to monitor current drawn from the AC adapter (DC Maximum 28V Input Voltage input source), battery-charging current, and the pres- > 95% Efficiency ence of an AC adapter. The MAX1908s conditioning charge feature provides 300mA to safely charge deeply Shutdown Control Input discharged lithium-ion (Li+) battery packs. Charge Any Battery Chemistry The MAX1908 includes a conditioning charge feature Li+, NiCd, NiMH, Lead Acid, etc. while the MAX8724/MAX8765/MAX8765A do not. Ordering Information The MAX1908/MAX8724/MAX8765/MAX8765A charge two to four series Li+ cells, providing more than 5A, and are PART TEMP RANGE PIN-PACKAGE available in a space-saving, 28-pin, thin QFN package (5mm MAX1908ETI+ -40C to +85C 28 Thin QFN-EP* 5mm). An evaluation kit is available to speed designs. MAX8724ETI+ -40C to +85C 28 Thin QFN-EP* Applications MAX8765ETI+ -40C to +85C 28 Thin QFN-EP* Notebook and Subnotebook Computers Personal Digital Assistants MAX8765AETI+ -40C to +85C 28 Thin QFN-EP* Handheld Terminals Functional Diagrams +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Minimum Operating Circuit Pin Configuration AC ADAPTER TO EXTERNAL 0.01 INPUT LOAD TOP VIEW CSSP CSSN CELLS DCIN LDO REFIN 21 20 19 18 17 16 15 VCTL BST LDO DLOV 22 14 ICTL DLOV GND ACIN 23 LX 13 ICTL MAX1908 DHI ACOK MAX8724 BST 24 12 REFIN MAX8765 LX FROM HOST P SHDN MAX8765A MAX1908 25 11 DHI ACOK DLO MAX8724 ICHG 10H 26 CSSN MAX8765 10 ACIN PGND IINP MAX8765A 27 CSSP 9 ICHG CSIP CCV IINP 28 8 SHDN CCI 0.015 CCS CSIN + BATT BATT+ 1 2 3 4 5 6 7 REF CLS GND Pin Configurations appear at end of data sheet. Functional Diagrams continued at end of data sheet. THIN QFN UCSP is a trademark of Maxim Integrated Products, Inc. For pricing, delivery, and ordering information, please contact Maxim Direct 19-2764 Rev 5 11/09 at 1-888-629-4642, or visit Maxims website at www.maxim integrated.com. AVAILABLE DCIN DLO LDO PGND CLS CSIP REF CSIN CCS CELLS CCI BATT CCV VCTLMAX1908/MAX8724/MAX8765/MAX8765A Low-Cost Multichemistry Battery Chargers ABSOLUTE MAXIMUM RATINGS DLOV, VCTL, ICTL, REFIN, CELLS, CLS, DCIN, CSSP, CSSN, ACOK to GND.......................-0.3V to +30V LDO, SHDN to GND .............................................-0.3V to +6V BST to GND............................................................-0.3V to +36V BST to LX..................................................................-0.3V to +6V DLOV to LDO.........................................................-0.3V to +0.3V DLO to PGND .........................................-0.3V to (V + 0.3V) DHI to LX...................................................-0.3V to (V + 0.3V) DLOV BST LX to GND .................................................................-6V to +30V LDO Short-Circuit Current...................................................50mA Continuous Power Dissipation (T = +70C) BATT, CSIP, CSIN to GND .....................................-0.3V to +20V A 28-Pin Thin QFN (5mm 5mm) CSIP to CSIN or CSSP to CSSN or PGND to GND ....................................................-0.3V to +0.3V (derate 20.8mW/C above +70C) .........................1666.7mW Operating Temperature Range ..........................-40C to +85C CCI, CCS, CCV, DLO, ICHG, IINP, ACIN, REF to GND.......................-0.3V to (V + 0.3V) Junction Temperature......................................................+150C LDO Storage Temperature Range .............................-60C 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 (V = V = V = 18V, V = V = V = 12V, V = 3V, V = V = 0.75 x V , CELLS = open, CLS = DCIN CSSP CSSN BATT CSIP CSIN REFIN VCTL ICTL REFIN REF, V - V = 4.5V, ACIN = GND = PGND = 0, C = 1F, LDO = DLOV, C = 1F CCI, CCS, and CCV are compensated BST LX LDO REF per Figure 1a T = 0C to +85C, unless otherwise noted. Typical values are at T = +25C.) A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS CHARGE-VOLTAGE REGULATION Battery-Regulation Voltage V = V -0.5 +0.5 VCTL REFIN Accuracy V = V /20 -0.5 +0.5 VCTL REFIN (MAX1908/MAX8724/MAX8765 % (2, 3, or 4 Cells) and MAX8765A V = V -0.5 +0.5 VCTL LDO (4 Cells Only)) V = V -0.4 +0.4 VCTL REFIN Battery-Regulation Voltage +0.4 Accuracy (MAX8765A, 2 or 3 V = V /20 -0.4 % VCTL REFIN Cells Only) +0.4 V = V -0.4 VCTL LDO VCTL Default Threshold V rising 4.0 4.1 4.2 V VCTL REFIN Range (Note 1) 2.5 3.6 V REFIN Undervoltage Lockout V falling 1.20 1.92 V REFIN CHARGE-CURRENT REGULATION CSIP-to-CSIN Full-Scale Current- V = V 71.25 75 78.75 mV ICTL REFIN Sense Voltage V = V -5 +5 ICTL REFIN V = V x 0.6 -5 +5 ICTL REFIN V = V -6 +6 ICTL LDO Charging-Current Accuracy % MAX8765/MAX8765A only V = V x ICTL REFIN -45 +45 0.036 MAX8724 only V = V x 0.058 -33 +33 ICTL REFIN Charge-Current Gain Error -2 +2 % (MAX8765/MAX8765A Only) Charge-Current Offset -2 +2 mV (MAX8765/MAX8765A Only) ICTL Default Threshold V rising 4.0 4.1 4.2 V ICTL BATT/CSIP/CSIN Input Voltage 0 19 V Range 2 Maxim Integrated