Datasheet

SLUU188 − March 2004
4
TPS40007-Based Converter Delivers 10-A Output
TPS40007-Based Converter Delivers 10-A Output
Mark Dennis DC to DC Controller Produc
ts
Contents
1 Introduction 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Features 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Schematic 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Design Procedure 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 PowerPAD Packaging 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 Test Results/Performance Data 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 PCB Layout 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 List of Material 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 Introduction
The TPS40007 is a voltage-mode, synchronous buck PWM controller that uses TI’s proprietary Predictive Gate
Drive technology to wring maximum efficiency from step-down converters. This controller provides a
bootstrap circuit to allow the use of an N-channel MOSFET as the topside buck switch to reduce conduction
losses and increase silicon device utilization. Predictive Gate Drive technology controls the delay from main
switch turn-off to synchronous rectifier turn-on and also the delay from rectifier turn-off to main switch turn-on.
This allows minimization of the losses in the MOSFET body diodes, both conduction and reverse recovery. This
design note provides details on a buck converter that converts an input of 3 V to 5 V down to a 2.5-V output level
using the TPS40007 controller.
A schematic for the board is shown in Figure 1. The list of material is provided in section 7 of this User’s Guide.
2 Features
The specification for this board is as follows:
D V
IN
= 3.3 V to 5 V
D V
OUT
= 2.5 V +/−3%
D I
OUT
= 0 A to 10 A
D Efficiency = > 95% with V
IN
= 3.3 V, I
LOAD
= 4 A
D Output voltage ripple < 2% V
OUT
D Power semiconductor devices: Each MOSFET is a single SO-8 package