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REV. 1.1.0 3/27/03

Pentium is a registered trademark of Intel Corporation. Athlon is a registered trademark of AMD. Programmable Active Droop is a trademark of Fairchild Semiconductor.

Block Diagram

22

VID0

11

10

14

13

17

16

24

-

+

OSC

Digital

Control

Power

Good

5-Bit

DAC

VID1

VID2

VID3

VID4

12 3 4 5

+12V

PWRGD

-

+

ENABLE/SS

VO

AGND

7

DROOP/E*

18

6

+12V

15

5V Reg

BYPASS

23

+12V

+12V

12

8

9

21

+12V

Digital

Control

-

+

-

+

-

+

19

ILIM

20

BOOT A

BOOT B

GNDA

Current

Limit

UVL O

FAN5093

Two Phase Interleaved Synchronous Buck Converter

for VRM 9.x Applications

Features

• Programmable output from 1.10V to 1.85V in 25mV steps

using an integrated 5-bit DAC

•Two interleaved synchronous phases for maximum

performance

• 100nsec transient response time

• Built-in current sharing between phases

• Remote sense

• Programmable switching frequency from 100KHz to

1MHz per phase

• Adaptive delay gate switching

• Integrated high-current gate drivers

• Integrated Power Good, OV, UV, Enable/Soft Start

functions

• Drives N-channel MOSFETs

• Operation optimized for 12V operation

• High efficiency mode (E*) at light load

•Overcurrent protection using MOSFET sensing

• 24 pin TSSOP package

Applications

• VRM for Pentium IV processor

• Programmable step-down power supply

Description

The FAN5093 is a synchronous two-phase DC-DC controller

IC which provides a highly accurate, programmable output

voltage for VRM 9.x processors. Two interleaved synchro-

nous buck regulator phases with built-in current sharing

operate 180° out of phase to provide the fast transient

response needed to satisfy high current applications while

minimizing external components.

transient response with minimum output capacitance. It has

integrated high-current gate drivers, with adaptive delay gate

switching, eliminating the need for external drive devices.

The FAN5093 uses a 5-bit D/A converter to program the

output voltage from 1.10V to 1.85V in 25mV steps with an

accuracy of 1%. The FAN5093 uses a high level of integra-

tion to deliver load currents in excess of 50A from a 12V

source with minimal external circuitry.

The FAN5093 also offers integrated functions including

Power Good, Output Enable/Soft Start, under-voltage lock-

out, over-voltage protection, and adjustable current limiting

with independent current sense on each phase. It is available

in a 24 pin TSSOP package.