SLUU131A – September 2002 – Revised February 2003
4
TPS40001 Based Converter Delivers 10-A Output
TPS40001 Based Converter Delivers 10-A Output
Mark Dennis
DC to DC Controller Products
Contents
1
Introduction
4
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2
Features
4
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3
Schematic
5
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3
Design Procedure
6
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4
PowerPAD Packaging
10
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5
Test Results/Performance Data
11
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6
PCB Layout
14
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7
List of Material
15
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1
Introduction
The TPS40000 and the TPS40001 are voltage-mode, synchronous buck PWM controllers that utilize TI’s
proprietary Predictive Gate Drive
technology to wring maximum efficiency from step-down converters. This
controller family 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 utilizing either the TPS40000 or TPS40001 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
= 3.0 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, load 4 A
D
Output voltage ripple < 2% V
OUT
D
Power semiconductor devices: Each MOSFET is a single SO-8 package
