MAX888

MAX886/MAX888 19-1438; Rev 0; 3/99 EVFAOLLULAOTWIOSNDKAITTAMSAHNEUEATL Wireless and Satellite Handset Power-Management ICs General Description The MAX886/MAX888 power-management ICs are complete power systems for wireless and satellite handsets. The devices operate from 3 to 6-cell NiCd/NiMH batteries or from 1 or 2-cell Li-Ion batteries. They incorporate a high-efficiency, step-down DC-DC converter, a regulated 5V charge pump, and four linear regulators. The regulators supply power to the SIM, LCD, BB, DSP, and RF sections of a cellular telephone handset. The step-down converter and linear regulator outputs are adjustable by internal 4-bit DACs, programmable through the I2C™compatible serial interface. A pushbutton on/off scheme activates a 5µA low-power shutdown mode. The devices also feature a low-battery detector output and an internal start-up timer. The MAX886/MAX888 differ in output voltage range and power-on reset voltage. The MAX886 has a higher preset voltage range and is intended for 2-cell Li-Ion or 5/6-cell NiCd/NiMH batteries. The MAX888 has a lower preset voltage range and is intended for 1-cell Li-Ion or 3/4-cell NiCd/NiMH batteries. Both devices are available in a space-saving, 32-pin TQFP package. Satellite Phones Wireless Handsets Applications Private Mobile Radio (PMR) GSM Cellular/PCS Telephones Pin Configuration appears at end of data sheet. Features o 90% Efficient, 500mA Step-Down Converter o Two 100mA DAC-Controlled LDOs One 200mA DAC-Controlle...