Other Parts Discussed in Thread: TPS54560, TPS54360
I'm working on a circuit using TPS54560 generating a 15V 2.6A output. The output voltage is around 15V and the chip is working, but there is a huge output ripple (the fluctuation is around 4-5V) and the frequency is very low, the period is at the order of seconds (about 1s) I've tested the waveform at SW pin and BOOT pin, both of the frequency is very low. I'm wondering what kind of mistake can lead to this phenomenon, and how can I fix this problem. The parameter is calculated using the excel tool downloaded from the TI website. And the schematic is pasted below. The picture is the waveform measured at the output.(There is another rail of voltage output generating -15V and that works well, not that much fluctuation, the voltage is quite stable.)
