Other Parts Discussed in Thread: TPS54540, , TPS54540B-Q1, LMR14050
Hi everyone
I am using a TPS54540 IC as the main buck converter in my system(to decrease 13 V to 5 V). Also, the system contains AM radio which its frequency band is 522 kHz- 1610 kHz. So, The TPS54540 switching frequency should be above 1.8 MHz. The TPS54540 delivers 5 V, 5 A properly when Fsw=1 MHz. But, when I increase the switching frequency (above 1.8 MHz), it can not deliver 5 A (it delivers 4A). As the current goes more than 4 A, large ripples appear on the output voltage which its frequency is under 10 kHz.
I wonder, does this IC can deliver 5 V, 5 A when the switching frequency is above 1.8 MHz without such ripples or not?
I appreciate any help in advance.
Armin