TPS53319EVM-136 contains a 10Ω series resistor in the feedback loop for loop response analysis.
- Set up EVM as described in Section 4 and Figure 4-2.
- Connect isolation transformer to test points marked TP6 and TP7.
- Connect input signal amplitude measurement probe (channel A) to TP6. Connect output signal amplitude measurement probe (channel B) to TP7.
- Connect ground lead of channel A and channel B to TP9.
- Inject around 20mV or less signal through the isolation transformer.
- Sweep the frequency from 100Hz to 1MHz with 10Hz or lower post filter. The control loop gain and phase margin can be measured.
- Disconnect isolation transformer from bode plot test points before making other measurements (Signal injection into feedback may interfere with accuracy of other measurements).