Step-Down Controller Targets Notebook CPUs

Intended as a dc-to-dc converter for the core CPU in notebook computers, MAX1711 offers ultra-fast transient response, high dc accuracy, and the high efficiency needed for leading edge CPU power supplies. The proprietary QUICK-PWM quick response, constant-on-time control scheme handles wide ratios of input/output voltage and maintains a relatively constant switching frequency while providing a 100 ns instant on response to load transients. MAX1711’s dc precision is ensured by a two-wire remote sensing scheme that compensates for voltage drops in the supply rail and the ground bus. An internal 5-bit DAC sets the output voltage in accordance with specifications of Intel’s Mobile Pentium II CPU. The output adjustment range is 0.925V to 2V and the reference voltage output is 2V, ±1%.