The ISL6211 is a single-output power-controller to power core of Transmeta's CrusoeTM CPU. The ISL6211 includes a 5-bit digital-to-analog converter (DAC) that adjusts the core PWM output voltage from 0.6VDC to 1.75VDC. The DAC settings may be changed during operation. Special measures are taken to allow such a transition with controlled slew rate to comply with Transmeta's LongRunTM technology. A precise reference and a proprietary architecture with integrated compensation provide excellent static and dynamic core voltage regulation. In nominal currents, the controller operates at a selectable frequency of 300kHz or 600kHz. When the filter inductor current becomes discontinuous, the controller operates in a hysteretic mode dramatically improving system efficiency. The hysteretic mode of operation can be inhibited by a designated control pin.