6 Test Procedure
6.1 Line and Load Regulation and Efficiency Measurement Procedure
1. Set up the EVM as described in
and
.
2. Ensure the load is set to constant resistance mode and to sink 0 ADC.
3. Ensure the jumper provided in the EVM shorts on J2 before V
IN
is applied.
4. Increase V
IN
from 0 V to 12 V, using V1 to measure input voltage.
5. Remove the jumper on J3 to enable the controller.
6. Use V2 to measure V
OUT
voltage.
7. Vary Load from 0 ADC to 25 ADC. V
OUT
should remain in load regulation.
8. Vary V
IN
from 8 V to 14 V. V
OUT
should remain in line regulation.
9. Put the jumper on J3 to disable the controller.
10. Decrease the load to 0 A.
11. Decrease V
IN
to 0 V.
6.2 Control Loop Gain and Phase Measurement Procedure
TPS53819AEVM-123 contains a place holder for a 10-Ω series resistor in the feedback loop for loop response
analysis.
1. Replace R16 with a 10-Ω resistor.
2. Set up EVM as described in
and
.
3. Connect isolation transformer to test points marked TP13 and TP11.
4. Connect input signal amplitude measurement probe (Loop B) to TP11. Connect output signal amplitude
measurement probe (Loop A) to TP13.
5. Connect ground lead of Loop A and Loop B to TP12.
6. Inject around 10 mV or less signal through the isolation transformer.
7. Sweep the frequency from 100 Hz to 1 MHz with 10 Hz or lower post filter. The control loop gain and phase
margin can be measured.
8. Disconnect isolation transformer from bode plot test points before making other measurements (Signal
injection into feedback can interfere with accuracy of other measurements).
6.3 Equipment Shutdown
1. Shut down the load.
2. Shut down V
IN
.
3. Shut down fan.
Test Procedure
12
TPS53819A Buck Controller Evaluation Module User's Guide
SLVU719B – MAY 2012 – REVISED NOVEMBER 2021
Copyright © 2021 Texas Instruments Incorporated
