Texas Instruments TPS40400, Руководство пользователя

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5.2 Test Equipment
5.2.1 Voltage Source
The input voltage source V
IN
should be a 0-V to 14-V variable DC source capable of supplying 10 A
DC
. Connect
V
IN
to J1 as shown in Figure 5-2 .
5.2.2 Multimeters
• DMM 1: V
IN
at TP1 (V
IN
) and TP3 (GND).
• DMM 2: Input current measured across Shunt 1.
• DMM 3: V
OUT
at TP5 (V
OUT
) and TP17 (GND).
• DMM 4: Output current measured across Shunt 2.
5.2.3 Output Load
The output load should be an electronic constant-resistance mode load capable of 0 A
DC
to 25 A
DC
at 1.2 V. An
electronic constant-current load is also acceptable.
5.2.4 Oscilloscope
A digital or analog oscilloscope can be used to measure the output ripple. To measure output ripple, the
oscilloscope should be set for 1-MΩ impedance, 20-MHz bandwidth, AC coupling, 2-µs/division horizontal
resolution, 50-mV/division vertical resolution. As shown below in
Figure 5-1 , test points TP5 and TP17 can be
used to measure the output ripple voltage by placing the oscilloscope probe tip through TP5 and holding the
ground barrel to TP17. It is not recommended to use a leaded ground connection because this may induce
additional noise due to the large ground loop.
To measure other waveforms, adjust the oscilloscope as needed.
TP17 TP5
Metal Ground Barrel
Probe Tip
Figure 5-1. Tip and Barrel Measurement for V
OUT
Ripple
www.ti.com Test Setup
SLUU535A – SEPTEMBER 2011 – REVISED JANUARY 2022
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TPS40400 Buck Controller Evaluation Module User's Guide 7
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