Datasheet

Notes
R6=26.7kfor3.3Vout,R6=16.2kfor5.0Vout
+
+
D3:Donotpopulate.SOT23CommonCathodeDualSchottky
0
50
1.0
80
60
70
100
90
0.5 1.5 2.0 2.5
Load Current (A)
Efficiency (%)
V
OUT
= 5 V
16
12
8
V
IN
(V)
0
50
1.0
80
60
70
100
90
0.5 1.5 2.0 2.5
Load Current (A)
Efficiency (%)
16
12
8
V
IN
(V)
V
OUT
= 3.3 V
TPS40200
www.ti.com SLUS659F –FEBRUARY 2006–REVISED MARCH 2012
DESIGN EXAMPLES
Application 1: Buck Regulator, 8-to-12 V Input, 3.3 V or 5.0 V at 2.5 A Output
Overview
The buck regulator design shown in Figure 31 shows the use of the TPS40200. It delivers 2.5 A at either 3.3 or
5.0 V as selected by a single feedback resistor. It achieves approximately 90 % efficiency at 3.3 V and 94% at
5.0 V. A discussion of design tradeoffs and methodology is included to serve as a guide to the successful design
of forward converters using the TPS40200.
The List of Materials for this application is given in Table 4. The efficiency and load regulation from boards built
from this design are shown in Figure 32 and Figure 33. Gerber files and additional application information are
available from the factory.
Figure 31. 8-to-16 V
IN
Step-Down Buck Converter
Figure 32. Full-Load Efficiency at 5.0 V
OUT
Figure 33. Full-Load Efficiency at 3.3 V
OUT
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Product Folder Link(s): TPS40200