
Fairchild Semiconductor
Description
The FAN5026 PWM controller provides high efficiency and regulation for two output voltages adjustable in the range of 0.9V to 5.5V required to power I/O, chip-sets, and memory banks in high-performance computers, set-top boxes, and VGA cards. Synchronous rectification and hysteretic operation at light loads contribute to high efficiency over a wide range of loads. Efficiency is enhanced by using MOSFET RDS(ON) as a current-sense component.
FEATUREs
■ Highly Flexible, Dual Synchronous Switching PWM Controller that 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 Over-Current Using Sense Resistor
■ VCC Under-Voltage Lockout
■ Wide Input Range: 3V to 16V
■ Excellent Dynamic Response with Voltage Feedforward and Average Current-Mode Control
■ Power-Good Signal
■ Supports DDR-II and HSTL
■ 28-Lead Thin-Shrink Small-Outline Package
APPLICATIONs
■ DDR VDDQ and VTT Voltage Generation
■ PC Dual Power Supply
■ Server DDR Power
■ Desktop Computer
■ Graphics Cards