Texas Instruments TPS54383, Руководство пользователя

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4.3 Start Up / Shut Down Procedure
1. Increase VIN from 0 V to 12 V
DC
.
2. Vary LOAD1 from 0 – 2 A
DC
3. Vary LOAD2 from 0 – 2 A
DC
4. Vary VIN from 9.6 V
DC
to 13.2 V
DC
5. Decrease VIN to 0 V
DC
6. Decrease LOAD1 to 0 A.
4.4 Output Ripple Voltage Measurement Procedure
1. Increase VIN from 0 V to 12 V
DC
.
2. Adjust LOAD1 to desired load between 0 A
DC
and 2 A
DC
.
3. Adjust VIN to desired load between 9.6 V
DC
and 13.2 V
DC
.
4. Connect oscilloscope probe to TP3 and TP4 or TP18 and TP19 as shown in Figure 4-2 .
5. Measure output ripple.
6. Decrease VIN to 0 V
DC
.
7. Decrease LOAD1 to 0 A.
4.5 Control Loop Gain and Phase Measurement Procedure
1. Connect 1 kHz to 1 MHz isolation transformer to TP6 and TP8 as show in Figure 4-3 .
2. Connect input signal amplitude measurement probe (Channel A) to TP8 as shown in Figure 4-3 .
3. Connect output signal amplitude measurement probe (Channel B) to TP6 as shown in Figure 4-3 .
4. Connect ground lead of Channel A and Channel B to TP5 & TP7 as shown in Figure 4-3 .
5. Inject 30 mV or less signal across R1 through isolation transformer.
6. Sweep frequency from 1 kHz to 1 MHz with 10 Hz or lower post filter.
7. Control loop gain can be measured by:
20
ChannelB
LOG
ChannelA
æ ö
´
ç ÷
è ø
8. Control loop phase is measured by the phase difference between Channel A and Channel B.
9. Control loop for Channel 2 can be measured by making the following substitutions.
a. Change TP6 to TP16
b. Change TP8 to TP14
c. Change TP5 to TP17
d. Change TP7 to TP15
10. Disconnect isolation transformer before making any other measurements (signal injection into feedback may
interfere with accuracy of other measurements).
4.6 Equipment Shutdown
1. Shut down oscilloscope
2. Shut down VIN
3. Shut down LOAD1
4. Shut down fan
www.ti.com Test Set Up
SLUU285D – JULY 2007 – REVISED OCTOBER 2021
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TPS54383 Step-Down Converter Evaluation Module User's Guide 11
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