DC/DC Controller Complies With VRM8.5 Specs

Readied for the latest generation of low-voltage CPUs, including Tualatin Pentium IIIs, the FAN5070 synchronous-mode dc/dc controller boast of an output that can be dynamically programmed over a 1.05V to 1.825V range in 25-mV steps using a five-bit VID D/A converter. This capability makes the device compliant with VRM8.5 specifications. In a 20-pin SOIC, the controller integrates high current drivers for external MOSFETs to output load currents up to 28A (typ.). Operating from 5V and 12V inputs, conversion efficiency exceeds 85% at full loads. Other features include remote-voltage sensing, overvoltage protection, undervoltage lockout, power-good indication, and enable/soft-start control. In addition, a programmable active droop is included with headroom up to 200 mV, thereby reducing the size of output capacitors required. User-adjustable current limiting is another feature of the chip. In tube or tape-and-reel packing, price is $1.35 each/1,000. FAIRCHILD SEMICONDUCTOR INTERNATIONAL, San Jose, CA. (888) 522-5372.