General Description

The FAN5026 PWM controller provides high efficiency and regulation for two output voltages adjustable in the range from 0.9V to 5.5V that are required to power I/O, chip-sets, and memory banks in high-performance computers, set top boxes, and VGA cards. Synchronous rectification contributes to high efficiency over a wide range of loads. Efficiency is even further enhanced by using MOSFET’s RDS(ON) as a current sense component.

Features

■ Highly flexible dual synchronous switching PWM controller includes modes for:

– DDR mode with in-phase operation for reduced channel interference

– 90° phase shifted two-stage DDR Mode for reduced input ripple

– Dual Independent regulators 180° phase shifted

■ Complete DDR Memory power solution

– VTT Tracks VDDQ/2

– VDDQ/2 Buffered Reference Output

■ Lossless current sensing on low-side MOSFET or Precision current sensing using sense resistor

■ VCC Under-voltage Lockout

■ Wide power input range: 3 to 16V

■ Excellent dynamic response with Voltage Feed-Forward and Average Current Mode control

■ Power-Good Signal

■ Supports DDR-II and HSTL

■ TSSOP28 package

Applications

■ DDR VDDQ and VTT voltage generation

■ Desktop computer

■ Graphics cards