ADP3164

a FEATURES ADOPT™ Optimal Positioning Technology for Superior Load Transient Response and Fewest Output Capacitors Complies with VRM 9.1 with Lowest System Cost 4-Phase Operation at up to 500 kHz per Phase Quad Logic-Level PWM Outputs for Interface to External High-Power Drivers Active Current Balancing between All Output Phases Accurate Multiple VRM Module Current Sharing 5-Bit Digitally Programmable 1.1 V to 1.85 V Output Total Output Accuracy ؎0.8% Over Temperature Current-Mode Operation Short Circuit Protection Enhanced Power Good Output Detects Open Outputs in Multi-VRM Power Systems Overvoltage Protection Crowbar Protects Microprocessors with No Additional External Components APPLICATIONS Desktop PC Power Supplies for: Intel Pentium® 4 Processors VRM Modules 5-Bit Programmable 4-Phase Synchronous Buck Controller ADP3164 FUNCTIONAL BLOCK DIAGRAM VCC ADP3164 UVLO & BIAS SET RESET CROWBAR REF GND DAC + 20% CT OSCILLATOR POWER GOOD 3.0V REFERENCE 4-PHASE DRIVER LOGIC PWM1 PWM2 PWM3 PWM4 PGND PWRGD SHARE CMP CMP DAC – 20% CS– CS+ FB gm SOFT START COMP VID DAC VID4 VID3 VID2 VID1 VID0 GENERAL DESCRIPTION The ADP3164 is a highly efficient 4-phase synchronous buck switching regulator controller optimized for converting a 12 V main supply into the core supply voltage required by high performance Intel processors. The ADP3164 uses an internal 5-bit DAC to read a voltage identification (VID) code directly from the processor, which is used to set the output voltage betwee...