MPM54304GMN-0004 Vout1+Vout2 Parallel Operation – Output Current Peaks and SW1 Frequency Variation

DC-DC Power Converters
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Hello, this is my first post on the forum.

I am using MPM54304GMN-0004 with Vout1 and Vout2 connected in parallel to supply 0.85 V to an AMD XCAU25P FPGA (VCCINT / VCCINT_IO / VCCBRAM). No I²C configuration has been written, so the device is operating in the default Forced-PWM mode (MODE=1).

The output voltage is stable, but the measured current (after the output capacitors) shows AC-like peaks exceeding 8 A. The datasheet specifies Vout1 + Vout2 max = 6 A. When measuring on the load side (after the output capacitors), is it normal to see such current peaks?

SW1 should be fixed at 800 kHz, but the measured switching frequency varies between ~190 kHz and 800 kHz. Even if COT is operating, the variation seems large. Is such a switching frequency variation expected in Forced-PWM mode, or does it indicate a potential design issue?

I have attached the measured waveforms for reference.

Thank you for your support.

Waveform1
Waveform11800×1300 201 KB

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Hi,

This AC behavior is unusual, especially after the output caps and with such high magnitude.

What is the frequency of your AC waveform? Frequency appears in figure 4.

Best,

Tyler

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