DESCRIPTION The APW7047 provides power control and protection for three output voltage applications on AGP/PCI graphics cards. It integrates two PWM controllers, a source library linear controller, as well as monitoring and protection functions in a single package. A PWM converter (PWM1) regulates the use of the GPU's core voltage (1.5V) synchronously. Buck converter. Other standard buck converters (PWM2's) regulate the VMEM voltage (2.5V) to power DDR memory. The source library linear controller controls two external MOSFETs and is a linear regulator with current sink capability. It regulates the VTT voltage (1.25V), the DDR termination supply voltage. Additional built-in overvoltage protection (OVP) will start when the core voltage or VMEM output is higher than 115% per DAC setting (core voltage and VMEM). The overvoltage protection function will shut down all output voltages until the IC is restarted. For each PWM converter, the overcurrent function monitors the output current by sensing the voltage drop across the MOSFET's RDS(ON), eliminating the need for a current sense resistor. ...

Features • 3 provide voltage regulation
- Synchronize. Buck converter to Vcore (1.15V~1.50V)
- For VMEM standard buck converters (2.40V~2.75V) nonlinear controllers, the source bank is the regulation voltage of VTT (1.25V)
• Simple single loop control design - voltage mode PWM control • Excellent output voltage regulation
- Core voltage output: ±2% over temperature range
-VMEM output: ±2% over temperature range
-VTT output: 1/2 ±25mV of VIN over minimum temperature. • Fast transient response when VIN = 1.7V
- Built-in feedback compensation
- Full 0% to 100% duty cycle • Over voltage and over current fault monitor • Constant frequency operation (200kHz) • 24 pins, SOIC package