©2005 Fairchild Semiconductor Corporation

1

www.fairchildsemi.com

December 2005

FAN5029 Product Brief Rev. 1.0.0

FAN5029

8-Bit Programmable 2- to 5-Phase Synchronous

Buck Controller

Features

1 MHz per phase

temperature

high-power drivers

fly VID code changes

both VR10 and VR11 specifications

mable latch-off delay

Applications

Intel processors

Description

The FAN5029 is a highly efficient multi-phase synchro-

nous buck switching regulator controller optimized for

converting a 12V main supply into the core supply volt-

age required by high performance Intel processors. It

uses an internal 8-bit DAC to read voltage identification

(VID) code directly from the processor, which is used to

set the output voltage between 0.5V and 1.6V. It uses a

multi-mode PWM architecture to drive the logic-level out-

puts at a programmable switching frequency that can be

optimized for VR size and efficiency. The phase relation-

ship of the output signals can be programmed to provide

2-, 3-, 4-, or 5-phase operation, allowing for the construc-

tion of up to five complementary buck switching stages.

The FAN5029 also includes programmable no-load off-

set and slope functions to adjust the output voltage as a

function of the load current, so that it is always optimally

positioned for a system transient. The FAN5029 also pro-

vides accurate and reliable short circuit protection,

adjustable current limiting, and a delayed Power Good

output that accommodates on-the-fly output voltage

changes requested by the CPU.

FAN5029 is specified over the extended commercial

temperature range of 0°C to +85°C and is available in a

40-lead MLP package.

Related Products

■ FAN5109MX – Dual Bootstrapped 12V MOSFET Driver

■ FAN5068 – DDR-1/DDR-2 plus ACPI Regulator Combo

■ FAN5069 – PWM and LDO Controller Combo

■ FAN6520A – Single Synchronous Buck PWM Controller

For more information, please contact

Ron Berthiaume at ronald.berthiaume@fairchildsemi.com