The MAX1501ZETE intelligent, constant-current, constant-voltage (CCCV), temperature-regulated battery charger charges a single lithium-ion (Li+) cell or three-cell NiMH/NiCd batteries. The device integrates the current-sense resistor, PMOS pass element, and thermal-regulation circuitry, while eliminating the reverse-blocking Schottky diode to create the simplest charging solution for hand-held equipment. For single-cell Li+ batteries, the MAX1501ZETE functions as a stand-alone charger to control the charging sequence from the prequalification state through fast charge, top-off, and charge termination. With 3-cell NiMH/NiCd batteries, the MAX1501ZETE requires collaboration with a microcontroller to determine the best charging algorithm. Proprietary thermal-regulation circuitry limits the die temperature when fast charging or while exposed to high ambient temperatures, allowing maximum charging current without damaging the charger. The MAX1501ZETE continually supplies a regulated output voltage under no-battery conditions, allowing battery changing without interrupting system power. The device achieves high flexibility by providing an adjustable fast-charge current, top-off current, safety timer (disabled in the MAX1501Z), and thermal-regulation setpoint. Other features include input power detection (active-low ACOK) and input under-/overvoltage protection. The MAX1501ZETE provides active-low control inputs. The MAX1501ZETE accepts a 4.5V to 13V supply, but disables charging when the input voltage exceeds 6.5V, preventing excessive power dissipation. The MAX1501ZETE operates over the extended temperature range (-40°C to +85°C) and is available in a compact 16-pin thermally enhanced 5mm x 5mm thin QFN package with 0.8mm profile.
Feature
- Stand-Alone 1-Cell Li+ Charging, Microprocessor- Controlled 3-Cell NiMH/NiCd Charging
- No FET, Reverse-Blocking Diode, or Current- Sense Resistor Required
- 1.4A (max) Programmable Fast-Charge Current
- +95°C, +115°C, and +135°C Proprietary Programmable Die Temperature Regulation Control
- 4.5V to 13V Input Voltage Range with Input Overvoltage (OVLO) Protection Above 6.5V
- Programmable Top-Off Current Threshold: 10%, 20%, or 30% of the Fast-Charge Current
- Charge-Current Monitor for Fuel Gauging
- Programmable Safety Timer (3, 4.5, or 6 hours)
- Input Power Detection Output (active-low ACOK) and Charge Enable Input (active-low CHGEN)
- Automatic Recharge
- Digital Soft-Start Limits Inrush Current
- Charge Status Outputs for LEDs or μP Interface
Applications
- Bluetooth? Equipment
- Cell Phones/Cordless Phones
- Charging Cradles and Docks
- Digital Cameras and MP3 Players
- PDAs
- USB Appliances
