ADP3178

www.DataSheet4U.com a FEATURES Optimally Compensated Active Voltage Positioning with Gain and Offset Adjustment (ADOPT™) for Superior Load Transient Response Complies with VRM Specifications with Lowest System Cost 4-Bit Digitally Programmable 1.3 V to 2.05 V Output N-Channel Synchronous Buck Driver Total Accuracy ؎0.8% Over Temperature Two On-Board Linear Regulator Controllers Designed to Meet System Power Sequencing Requirements High Efficiency Current-Mode Operation Short Circuit Protection for Switching Regulator Overvoltage Protection Crowbar Protects Microprocessors with No Additional External Components APPLICATIONS Core Supply Voltage Generation for: Intel Pentium® III Intel Celeron™ 4-Bit Programmable Synchronous Buck Controllers ADP3158/ADP3178 FUNCTIONAL BLOCK DIAGRAM VCC CT ADP3158/ ADP3178 UVLO & BIAS OSCILLATOR PWM DRIVE DRVL REFERENCE REF GND DRVH VLR1 LRFB1 CMP – + LRDRV1 VLR2 LRFB2 DAC+20% CS– CS+ gm LRDRV2 COMP REF VID DAC VID3 VID2 VID1 VID0 GENERAL DESCRIPTION The ADP3158 and ADP3178 are highly efficient synchronous buck switching regulator controllers optimized for converting a 5 V main supply into the core supply voltage required by highperformance processors. These devices use an internal 4-bit DAC to read a voltage identification (VID) code directly from the processor, which is used to set the output voltage between 1.3 V and 2.05 V. They use a current mode, constant off-time architecture to drive two N-channel MOSFETs at a programmable swi...