SLUSCC7C July 2016 – June 2018 TPS546C23
The devices implement a differential remote-sense amplifier to provide excellent load regulation by cancelling IR-drop in high-current applications. The RSP and RSN pins should be kelvin-connected to the output capacitor bank directly at the load, and routed back to the device as a tightly coupled differential pair. Ensure that these traces are isolated from fast switching signals and high current paths on the final PCB layout, as these can add differential-mode noise. Optionally, use a small coupling capacitor (1-nF typical) between the RSP and RSN pins to improve noise immunity. The output of the differential remote sense amplifier (DIFFO) is used for output voltage setting and error amplifier frequency compensation local to the device as shown in Figure 25.
The devices use voltage mode control with input feedforward. Frequency compensation can be accomplished using standard Type III techniques as shown in Figure 25.
In 2-phase configuration, the FB pin of the loop slave device should be tied to BP3 and the typical application circuit is shown in Figure 23. The loop master passes the internal COMP voltage through VSHARE pin to the loop slave device. For more information, see the Current Sharing section.
Additionally, the voltage at the DIFFO pin is digitized, averaged to reduce measurement noise and continually stored in the READ_VOUT command, enabling output voltage telemetry.