GENERAL DESCRIPTION
The ADP3166 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 AMD processors. It 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 between 0.8 V and 1.55 V. The ADP3166 also uses a multimode PWM architecture to drive the logic-level outputs at a programmable switching frequency that can be optimized for VRM size and efficiency. The phase relationship of the output signals can be programmed to provide 2-, 3-, or 4-phase operation, allowing for the construction of up to four complementary buck switch ing stages.
The ADP3166 includes programmable no-load offset and slope functions to adjust the output voltage as a function of the load current so that it is always optimally positioned for a system transient. The ADP3166 also provides accurate and reliable short-circuit protection, adjustable current limiting, and a delayed power good output that accommodates on-the-fly output volt age changes requested by the CPU.
ADP3166 is specified over the commercial temperature range of 0°C to 85°C and is available in a 28-lead TSSOP package.

FEATURES
  Selectable 2-, 3- or 4-Phase Operation at up to
     1 MHz per Phase
  Differential Sensing Error ±1% over Temperature
  Logic-Level PWM Outputs for Interface to
     External High Power Drivers
  Active Current Balancing between All Output Phases
  Built-in Power Good Blanking Supports On-the-Fly
     VID Code Changes
  5-Bit Digitally Programmable 0.8 V to 1.55 V Output
  Short-Circuit Protection with Programmable
     Latch-Off Delay
  Overvoltage Protection Crowbar Logic Output

APPLICATIONS
  Desktop PC Power Supplies
     Next-Generation AMD Processors
     VRM Modules