US3027

US3027 5 BIT PROGRAMMABLE SYNCHRONOUS BUCK PLUS TRIPPLE LDO CONTROLLER PRELIMINARY DATASHEET FEATURES Designed to meet VRM 9.0 specification for next generation micrprocessors On board 5 bit DAC programs the output voltage from 1.075V to 1.850V in 25mV steps Linear regulator controller on board for 1.8V Provides Single Chip Solution for Vcore, GTL+ ,AGP Bus, and 1.8V Automatic Voltage Selection for AGP slot Vddq supply Linear regulator controller on board for 1.5V GTL+ supply Loss less Short Circuit Protection for all outputs Synchronous operation allows maximum efficiency Patented architecture allows fixed frequency operation as well as 100% duty cycle during dynamic load Minimum part count Soft Start High current totem pole driver for direct driving of the external Power MOSFET Power Good function Monitors all Outputs OVP Circuitry Protects the Switcher Output and generates a Fault output DESCRIPTION The US3027 controller IC is specifically designed to meet VRM 9.0 specification for next generation microprocessor applications requiring multiple on board regulators . The US3027 provides a single chip controller IC for the Vcore , 3LDO controllers, one with the automatic select pin that connects to the TYPE DETECT pin of the AGP slot for the AGP Vddq supply, one for GTL+ and the other for the 1.8V chip set regulator as required for the next generation PC applications. The US3027 is designed to use either Bipolar transistors for Vout3(1.5V) and Vout4(1.8V) or if Vaux pin is ...