Hello team,
See below customer question:
I am having some issues with the TPS23754 and transient current changed. As we have talked about in the past we are doing some POE+ amplifier designs and I am able to get full sine wave output of 20W with our design but we are having issues with stability of the TPS23754 when large changes in current occur which is common in audio or when music starts or stops. Looking at the scope when the device is idle I am seeing a 12% duty cycle on the gate of the mosfet. When at 20W of audio output I am seeing ~40% duty cycle so these are well within the expected parameters. The issue I see is when there is a transition from high loading to light loading the gate output becomes unstable and starts pulsing like the device is restarting. After this state is the device lightly loads then the switching wave form will stabilize most times but if it is hit with a large transient in current demand then the device reboots. I have already tries adding extra bulk capacitance and the design has 660uF on the output of the regulator and 100uF on each side of the amplifier ic. There is an additional 44uF on the input side of the poe regulator. Any help would be greatly appreciated. We used app note slvrb41b with suggested modifications from your design team to implement this design.
