SLVUBQ1A August 2020 – May 2021 TPS543620
Figure 3-10 and Figure 3-11 show the response to load transients for both designs. The current step is from 1.5 A to 4.5 A and the current step slew rate is 1 A/µs. An electronic load is used to provide a DC 1.5-A load and the load transient circuit on the EVM is used to provide a 3-A step. The VOUT voltage is measured using TP10 for U1 and TP29 for U2.
When using the load transient circuit included on the TPS543620EVM, slowly increase amplitude of function generator for desired load step amplitude then vary the rise and fall times for the desired slew rate. The current for the load step can be sensed with the ISNS test point. The default resistors on the EVM provide a gain of 20 A/V. With this gain, a 3-A step will result in 150-mV at the ISNS test point.
To use the load transient circuit with U1, move R27 to R28.