View max649 m datasheet:

19-0225; Rev 3; 9/97 5V/3.3V/3V or Adjustable, High-Efficiency, Low I , Step-Down DC-DC Controllers Q _______________General Description ____________________________Features The MAX649/MAX651/MAX652 BiCMOS, step-down DC- ¦ More than 90% Efficiency (10mA to 1.5A Loads) DC switching controllers provide high efficiency over ¦ More than 12.5W Output Power three decades of load current. A unique, current-limited ¦ 100µA Max Quiescent Supply Current pulse-frequency-modulated (PFM) control scheme gives these devices the benefits of pulse-width-modulation ¦ 5µA Max Shutdown Supply Current (PWM) converters (high efficiency at heavy loads), while ¦ Less than 1.0V Dropout Voltage using only 100µA of supply current (vs. 2mA to 10mA for ¦ 16.5V Max Input Voltage PWM converters). The res