The MAX1692 is a low-noise, pulse-width-modulated (PWM), DC-DC step-downconverter. It powers logic and transmitters in small wireless systems such as cellular phones,communicating PDAs, and handy-terminals. The device features an internal synchronous rectifier for highefficiency; it requires no external Schottky diode. Excellent noise characteristics and fixed-frequencyoperation provide easy post-filtering. The MAX1692 is ideally suited for Li-Ion battery applications. It isalso useful for +3V or +5V fixed input applications.

The device operates in one of four modes. Forced PWM mode operates at a fixed frequency regardless ofthe load. Synchronizable PWM mode allows an external switching frequency to control and minimizeharmonics. Idle Mode™ (PWM/PFM) extends battery life by switching to a PFM pulse-skipping mode duringlight loads. Shutdown mode places the device in standby, reducing quiescent supply current to under0.1µA.

The MAX1692 can deliver over 600mA. The output voltage can be adjusted from 1.25V to VIN with theinput range of +2.7V to +5.5V. Other features of the MAX1692 include high efficiency, low dropout voltage,and a 1.2%-accurate 1.25V reference. It is available in a space-saving 10-pin µMAX package with aheight of only 1.11mm.