MAX1873REEE+T

19-2099; Rev 0; 7/01 ILABLE N KIT AVA EVALUATIO Simple Current-Limited Switch-Mode Li+ Charger Controller The low-cost MAX1873R/S/T provides all functions needed to simply and efficiently charge 2-, 3-, or 4series lithium-ion cells at up to 4A or more. It provides a regulated charging current and voltage with less than ±0.75% total voltage error at the battery terminals. An external P-channel MOSFET operates in a step-down DC-DC configuration to efficiently charge batteries in low-cost designs. The MAX1873R/S/T regulates the battery voltage and charging current using two control loops that work together to transition smoothly between voltage and current regulation. An additional control loop limits current drawn from the input source so that AC adapter size and cost can be minimized. An analog voltage output proportional to charging current is also supplied so that an ADC or microcontroller can monitor charging current. The MAX1873 may also be used as an efficient currentlimited source to charge NiCd or NiMH batteries in multichemistry charger designs. The MAX1873R/S/T is available in a space-saving 16-pin QSOP package. Use the evaluation kit (MAX1873EVKIT) to help reduce design time. Applications Features o Low-Cost and Simple Circuit o Charges 2-, 3-, or 4-Series Lithium-Ion Cells o AC Adapter Input-Current-Limit Loop o Also Charges Ni-Based Batteries o Analog Output Monitors Charge Current o ±0.75% Battery-Regulation Voltage o 5µA Shutdown Battery Current o Input Voltage Up to 28V o 200mV Dropout Voltage/100% Duty Cycle o Adjustable Charging Current o 300kHz PWM Oscillator Reduces Noise o Space-Saving 16-Pin QSOP o MAX1873 Evaluation Kit Available to Speed Designs Ordering Information PART TEMP. RANGE PIN-PACKAGE MAX1873REEE -40°C to +85°C 16 QSOP Notebook Computers MAX1873SEEE -40°C to +85°C 16 QSOP Portable Internet Tablets MAX1873TEEE -40°C to +85°C 16 QSOP 2-, 3-, or 4-cell Li+ Battery Pack Chargers Typical Operating Circuit 6-, 9-, or 10-cell Ni Battery Pack Chargers Hand-Held Instruments Portable Desktop Assistants (PDAs) Desktop Cradle Chargers SYSTEM LOAD VIN 9V TO 28V (9V MIN FOR 2CELLS) VH VL Selector Guide DCIN CSSP MAX1873 CSSN PART SERIES CELLS TO CHARGE 4V OUT PER 200mV ON RCS MAX1873REEE 2-Cell Li+ or 5- or 6-cell Ni Battery MAX1873SEEE 3-Cell Li+ or 7- or 9-cell Ni Battery ICHG/EN MAX1873TEEE 4-Cell Li+ 10-cell Ni Battery Packs REF IOUT EXT CSB BATT CCI VADJ Pin Configuration appears at end of data sheet. CCS GND CCV 2- TO 4-CELL Li+ ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX1873 General Description MAX1873 Simple Current-Limited Switch-Mode Li+ Charger Controller ABSOLUTE MAXIMUM RATINGS CSSP, CSSN, DCIN to GND ...................................-0.3V to +30V VL, ICHG/EN to GND................................................-0.3V to +6V VH, EXT to DCIN.......................................................-6V to +0.3V VH, EXT to GND ......................................(VDCIN + 0.3V) to -0.3V EXT to VH .................................................................+6V to -0.3V DCIN to VL..............................................................+30V to -0.3V VADJ, REF, CCI, CCV, CCS, IOUT to GND.............................................-0.3V to (VL + 0.3V) BATT, CSB to GND.................................................-0.3V to +20V CSSP to CSSN.......................................................-0.3V to +0.6V CSB to BATT..........................................................-0.3V to +0.6V VL Source Current ............................................................+50mA VH Sink Current ................................................................+40mA Continuous Power Dissipation (TA = +70°C) 16-Pin QSOP (derate 8.3mW/°C above +70°C..........+667mW Operating Temperature Range MAX1873_EEE ................................................-40°C to +85°C Junction Temperature ..................................................... +150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) ................................ +300°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 (Circuit of Figure 1, VDCIN = VCSSP = VCSSN = 18V, VICHG/EN = VREF, VVADJ = VREF/2. MAX1873R: VBATT = VCSB = 8.4V; MAX1873S: VBATT = VCSB = 12.6V; MAX1873T: VBATT = VCSB = 16.8V; TA = 0°C to +85°C. Typical values are at TA = +25°C, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS INPUT SUPPLY AND REFERENCE DCIN Input Voltage Range DCIN Quiescent Supply Current 6 6.0V < VDCIN < 28V DCIN ≤ BATT 28 V 4 7 mA 0.1 10 µA DCIN to BATT Undervoltage Threshold CSSP = DCIN, input falling 0.05 0.175 V DCIN to BATT Undervoltage Threshold CSSP = DCIN, input rising 0.22 0.38 V VL Output Voltage 6.0V < VDCIN < 28V 5.15 5.40 5.65 V VL Output Load Regulation IVL = 0 to 3mA 15 50 mV REF Output Voltage IREF = 21µA (200kΩ load) 4.179 4.20 4.221 V 2 6 mV 22 65 ppm/V 6 13 mV 300 330 kHz 4 7 Ω 2.5 4.5 Ω REF Line Regulation 6.0V < VDCIN < 28V REF Load Regulation IREF = 0 to 1mA SWITCHING REGULATOR PWM Oscillator Frequency 270 EXT Driver Source On-Resistance EXT Driver Sink On-Resistance VH Output Voltage DCIN - VH, 6V < VDCIN