General Description

The APW7046 provides the power controls and protections for three output voltages on AGP/PCI Graphic Card applications. It integrates two PWM controllers , one SOURCE-SINK linear controller, as well as the monitor and protection functions into a single package. One PWM converter (PWM1) supplies the VCORE(1.5V) for the GPU with a standard buck converter. The other standard buck converter (PWM2) regulates the VMEM(2.5V) for the power of DDR memory. The SOURCE-SINK linear controller control two external MOSFETs to be a linear regulator with the capability of sourcing and sinking current. It regulates the VTT (1.25V) power for DDR Termination voltage.

Features

• 3 Regulated Voltages are provided

− Standard Buck Converter for VCORE (1.15~1.50V)

− Standard Buck Converter for VMEM (2.40~3.15V)

−Linear Controller with SOURCE-SINK Regulation for VTT(1.25V)

• Simple Single-Loop Control Design

− Voltage-Mode PWM Control

• Excellent Output Voltage Regulation

− VCORE Output : ±1 Over Temperature

− VMEM Output : ±1.5 Over Temperature

− VTT Output : 1/2 VIN ±25mV Over Temperature Min. VIN = 1.7V

• Fast Transient Response

− Built-in Feedback Compensation

− Full 0 to 100 Duty Ratio

• Over-Voltage and Over-Current Fault Monitor

• Constant Frequency Operation(200kHz)

• 24 pins, SOIC Package

Applications

• M/B DDR Power Regulation

• AGP/PCI Graphics Power Regulation

• SSTL-2 Termination