ANALOG DEVICES MAX1651CSA+

The MAX1651CSA+ is a 3.3V or adjustable, high efficiency, low dropout, step down DC to DC controller in 8 pin NSOIC package. The BiCMOS, step down, DC to DC switching controller provides high efficiency over loads ranging from 1mA to more than 2.5A. A unique, current limited pulse-frequency-modulated (PFM) control scheme gives this device the benefits of pulse width modulation (PWM) converter (high efficiency at heavy loads) while using only 100µA of supply current. Dropout performance down to 300mV is provided by a high switch duty cycle 96.5% and a low current-sense threshold of 110mV. A high switching frequency up to 300KHz allows this device to use miniature external components. It has a dropout voltage less than 0.3V at 500mA and accepts input voltages up to 16V. The step-down controllers drive external P-channel MOSFETs at loads greater than 12.5W. If less power is required, use the MAX639/MAX640/MAX653 step-down converters with on-chip FETs which allow up to 225mA load current.