MAX1717

19-1636; Rev 0; 1/00 KIT ATION EVALU E L B AVAILA Dynamically Adjustable, Synchronous Step-Down Controller for Notebook CPUs General Description Features o Quick-PWM Architecture o ±1% VOUT Accuracy Over Line and Load o 5-Bit On-Board DAC with Input Mux o Precision-Adjustable VOUT Slew Control o 0.925V to 2V Output Adjust Range o Supports Voltage-Positioned Applications o 2V to 28V Battery Input Range o Requires a Separate +5V Bias Supply o 200/300/550/1000kHz Switching Frequency o Over/Undervoltage Protection o Drives Large Synchronous-Rectifier FETs o 700µA typ ICC Supply Current o 2µA typ Shutdown Supply Current o 2V ±1% Reference Output o VGATE Transition-Complete Indicator o Small 24-Pin QSOP Package MAX1717 The MAX1717 step-down controller is intended for core CPU DC-DC converters in notebook computers. It features a dynamically adjustable output, ultra-fast transient response, high DC accuracy, and high efficiency needed for leading-edge CPU core power supplies. Maxim’s proprietary Quick-PWM™ quick-response, constant-on-time PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns “instant-on” response to load transients while maintaining a relatively constant switching frequency. The output voltage can be dynamically adjusted through the 5-bit digital-to-analog converter (DAC) inputs over a 0.925V to 2V range. A unique feature of the MAX1717 is an internal multiplexer (mux) that accepts two 5-bit DAC settings with only five digital ...