3.3.1 Input Voltage Monitoring (TP1 and TP2)
TPS54386EVM provides two test points for measuring the voltage applied to the module. This allows the
user to measure the actual module voltage without losses from input cables and connectors. All input voltage
measurements should be made between TP1 and TP2. To use TP1 and TP2, connect a voltmeter positive
terminal to TP1 and negative terminal to TP2.
3.3.2 Channel 1 Output Voltage Monitoring (TP3 and TP4)
TPS54386EVM provides two test points for measuring the voltage generated by the module. This allows the
user to measure the actual module output voltage without losses from output cables and connectors. All output
voltage measurements should be made between TP3 and TP4. To use TP3 and TP4, connect a voltmeter
positive terminal to TP3 and negative terminal to TP4. For Output ripple measurements, TP3 and TP4 allow a
user to limit the ground loop area by using the Tip and Barrel measurement technique shown in
. All
output ripple measurements should be made using the Tip and Barrel measurement.
3.3.3 Channel 1 Loop Analysis (TP5, TP6, TP7 and TP8)
TPS54386EVM contains a 51-Ω series resistor (R1) in the feedback loop to allow for matched impedance signal
injection into the feedback for loop response analysis. An isolation transformer should be used to apply a small
(30 mV or less) signal across R1 through TP6 and TP8. By monitoring the ac injection level at TP8 and the
returned ac level at TP6, the power supply loop response can be determined.
3.3.4 Channel 1 Switching Waveforms (TP9 and TP10)
TPS54386EVM provides a test point and a local ground connection (TP10) for the monitoring of the Channel 1
power stage switching waveform. Connect an oscilloscope probe to TP9 to monitor the switch node voltage for
Channel 1.
3.3.5 TPS54386 Device Ground (TP11)
TPS54386EVM provides a test point for the device ground. To measure the device pin voltages, connect the
ground of the oscilloscope probe to TP11.
3.3.6 Channel 2 Switching Waveforms (TP12 and TP13)
TPS54386EVM provides a test point and a local ground connection (TP13) for the monitoring of the Channel 1
power stage switching waveform. Connect an oscilloscope probe to TP12 to monitor the switch node voltage for
Channel 1.
3.3.7 Channel 2 Loop Analysis (TP14, TP15, TP16 and TP17)
TPS54386EVM contains a 51-Ω series resistor (R10) in the feedback loop to allow for matched impedance
signal injection into the feedback for loop response analysis. An isolation transformer should be used to apply a
small (30 mV or less) signal across R10 through TP14 and TP16. By monitoring the ac injection level at TP14
and the returned ac level at TP16, the power supply loop response can be determined.
3.3.8 Output Voltage Monitoring (TP18 and TP19)
TPS54386EVM provides two test points for measuring the voltage generated by the module. This allows the
user to measure the actual module output voltage without losses from output cables and connector losses. All
output voltage measurements should be made between TP18 and TP19. To use TP18 and TP19, connect a
voltmeter positive terminal to TP18 and negative terminal to TP19. For output ripple measurements, TP18 and
TP19 allow a user to limit the ground loop area by using the Tip and Barrel measurement technique shown in
. All output ripple measurements should be made using the Tip and Barrel measurement.
Schematic
6
TPS54x86 Step-Down Converter Evaluation Module User's Guide
SLUU286A – MARCH 2008 – REVISED OCTOBER 2021
Copyright © 2021 Texas Instruments Incorporated