ADP3181

5-Bit or 6-Bit Programmable 2-,3-,4-Phase Synchronous Buck Controller ADP3181 FEATURES Selectable 2-, 3- or 4-phase operation at up to 1 MHz per phase ±14.5 mV worst-case mV differential sensing error over temperature Logic-level PWM outputs for interface to external high power drivers Active current balancing between all output phases Built-in power good/crowbar blanking supports on-the-fly VID code changes Digitally programmable output can be switched between VRM 9 (5-bit) and VRD 10 (6-bit) VID codes Programmable short-circuit protection with programmable latch-off delay FUNCTIONAL BLOCK DIAGRAM VCC 28 RAMPADJ RT 14 13 ADP3181 EN 11 GND 19 DAC + 300mV CSREF CURRENTBALANCING CIRCUIT CMP RESET 2-/3-/4-PHASE DRIVER LOGIC RESET RESET CURRENT LIMIT 23 22 26 UVLO SHUTDOWN AND BIAS OSCILLATOR CMP SET RESET EN 27 PWM1 PWM2 CMP DAC – 250mV CMP PWRGD 10 DELAY 25 PWM3 PWM4 24 CROWBAR SW1 SW2 SW3 SW4 CSSUM CSREF CSCOMP APPLICATIONS Desktop PC power supplies for: Next-generation Intel® processors VRM modules ILIMIT 15 EN CURRENTLIMITING CIRCUIT 21 20 17 16 DELAY 12 GENERAL DESCRIPTION The ADP3181 is a highly efficient multiphase synchronous buck-switching regulator controller optimized for converting a 12 V main supply into the core supply voltage required by high performance Intel processors. It uses an internal 6-bit DAC to read a voltage identification (VID) code directly from the processor, which is used to set the output voltage. The CPUID input selects whether th...