MP8030 excess current draw

DC-DC Power Converters
1

Hi - I’m working with the MP8030GQJ and we are seeing a small but unexpected number of devices in our build that are failing test due to excessive current draw from the MP8030GQJ circuit while under minimal loading.

We are replicating the EVL8030-QJ-01A reference design.

The current draw increases by about 40mA from a 52V VDD supply in the failing boards.

This is repeatable if the board is powered up while the VOUT hasn’t been fully discharged. It seems more likely to occur when VOUT is at 0.7V when power is applied to the system, but at times is difficult to replicate exactly.

We see this even when the circuit is disconnected from any additional circuitry downstream. It seems be an issue with the sync circuit, the current seems to be at least partially going through Q3 from the reference design.

Output ripple also has an interesting characteristic while in the failure mode. The ripple in the output in normal mode is 250kHz and clean

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Any help debugging would be appreciated - thanks.

2

SYNC signal has a ‘glitch’ in the abnormal operating state

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3

Hi @hattie.spetla,

We are discussing the same issue over the email. We shall continue over the email. Once we have figured the issue, I’ll post the conclusion here for the community.

Thank you
Saurabh

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