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LM27403: On-time SW-node Jitter

Part Number: LM27403

Hello,

I am experiencing some on-time jitter on the switching-node output of my LM27403 circuit. I can provide all component values if needed, however I have observed the same node on the LM27403EVM and the percentage of jitter measured is almost identical to my design.

My design: load of 4.5A at 1.8V (taken using an electronic load, but I confirmed that the jitter is still present with a purely resistive load). Jitter percentage seems constant over the full output swing and load (designed to drive up to 2V and 10A). Switching frequency is nominally 1.18MHz.

LM27403EVM in its default (out-of-the-box) state:

Do you consider this normal for this converter, or do you think I could improve this output waveform so that there is less duty-cycle variation from cycle-to-cycle?

I can see that in applications notes such as this: Not All Jitter Is Created Equal (Rev. A) (ti.com)

20ns of steady-state jitter may be considered "normal".

Kind regards,

Stephen