MAX8836Z

19-4059; Rev 1; 9/08 www.DataSheet4U.com 1.2A PWM Step-Down Converter in 2mm x 2mm WLP/UCSP for PA Power General Description The MAX8836Z high-frequency step-down converter is optimized to provide a fixed output voltage with ultralow dropout. The device integrates a high-efficiency PWM step-down converter for medium- and low-power transmission, and a 60mΩ typical bypass FET for ultra low-dropout operation. A 200mA low-noise, high-PSRR low-dropout regulator (LDO) is also integrated. Fast-switching allows the use of small ceramic input and output capacitors while maintaining low ripple voltage. The feedback network is integrated, further reducing external component count and total solution size. At high duty cycle, the MAX8836Z automatically switches to the bypass mode, connecting the input to the output through a low-impedance (60mΩ typ) MOSFET. The LDO in the MAX8836Z is designed for low-noise operation (35µVRMS typ). Both the PWM step-down and LDO are individually enabled through separate logic-control interfaces. The MAX8836Z is available in 16-bump, 2mm x 2mm WLP and UCSP™ packages (0.7mm max height). Features o PA Step-Down Converter Selectable Output Voltage (3.1V or 3.4V) 25µs Settling Time for 3.1V to 3.4 VOUT Change 60mΩ PFET at 100% Duty-Cycle for Low Dropout Low Output Voltage Ripple 1.2A Output Drive Capability ±2% Output Voltage Accuracy Tiny External Components o Low-Noise LDO Low 35µVRMS (typ) Output Noise High 65dB (typ) PSRR Guaranteed 200mA Output Current ...