August 2007
FAN5109B
Dual Bootstrapped 12V MOSFET Driver
Features
Drives N-Channel High-Side and Low-Side MOSFETs
in a Synchronous Buck Configuration
Enhanced Upgrade to FAN5109
Direct Interface to FAN5029/FAN5182 and Other
Compatible PWM Controllers
12V High-Side and 12V Low-Side Drive
Internal Adaptive Shoot-Through Protection
Fast Rise and Fall Times
Switching Frequency Above 500kHz
OD Input for Output Disable – Allows Synchronization
with PWM Controller
SOIC-8 Package
TTL-Compatible Logic Inputs (New)
Description
The FAN5109B is a dual, high-frequency MOSFET
driver, specifically designed to drive N-channel power
MOSFETs in a synchronous-rectified buck converter.
These drivers, combined with a Fairchild multi-phase
pulse-width-modulated (PWM) controller and power
MOSFETs, form a complete core voltage regulator
solution for advanced microprocessors.
The FAN5109B drives the upper and lower MOSFET
gates of a synchronous buck regulator to 12VGS. The
output drivers have the capacity to efficiently switch
power MOSFETs at frequencies above 500KHz. The
circuit's adaptive shoot-through protection prevents both
MOSFETs from conducting simultaneously.
The FAN5109B is rated for operation from 0°C to +85°C
and is available in a low-cost SOIC-8 package.
Applications
Multi-Phase VRM/VRD Regulators for
Microprocessor Power
High-Current, High-Frequency DC/DC Converters
High-Power Modular Supplies
General-Purpose TTL Input MOSFET Drivers
Related Applications Notes
Application Note AN-6003, "Shoot-through" in
Synchronous Buck Converters
Ordering Information
Part Number Pb-Free
Operating
Temperature Range
Package Packing Method Quantity Per Reel
FAN5109BMX
Yes
0°C to 85°C
SOIC-8 Tape and Reel
2500
Note:
1. Contact a Fairchild sales representative for availability of leaded (Pb) parts.
© 2006 Fairchild Semiconductor Corporation
FAN5109B Rev. 1.0.0
www.fairchildsemi.com