ADP3167

The ADP3160 and ADP3167 are highly efficient, dual output, synchronous buck switching regulator controllers optimized for converting a 5 V or 12 V main supply into the core supply voltage required by high-performance processors, such as Pentium 4 and Athlon. The ADP3160 and ADP3167 use an internal 5-bit DAC to read a voltage identification (VID) code directly from the processor that is used to set the output voltage between 1.1 V and 1.85 V. The devices use a current-mode PWM architecture to drive two logiclevel outputs at a programmable switching frequency that can be optimized for VRM size and efficiency. The output signals are 180 degrees out of phase, allowing for the construction of two complementary buck switching stages. These two stages share the dc output current to reduce overall output voltage ripple. An active current balancing function ensures that both phases carry equal portions of the total load current, even under large transient loads, to minimize the size of the inductors. The ADP3160 control loop has been optimized for conversion from 12 V, while the ADP3167 is designed for conversion from a 5 V supply.

The ADP3160 and ADP3167 also use a unique supplemental regulation technique called active voltage positioning to enhance load transient performance. Active voltage positioning results in a dc/dc converter that meets the stringent output voltage specifications for high-performance processors, with the minimum number of output capacitors and smallest footprint. Unlike voltage-mode and standard current-mode architectures, active voltage positioning adjusts the output voltage as a function of the load current so that it is always optimally positioned for a system transient. They also provide accurate and reliable short circuit protection and adjustable current limiting. The ADP3160 and ADP3167 are specified over the commercial temperature range of 0 to 70 and is available in a 16-lead narrow body SOIC package.