TPS62140: Is Gain/phase margin measurement necessary for DCS mode solution?

Stan Wu

Intellectual 580 points

Part Number: TPS62140

Hello TI,

If I follow the recommended LC value on output filter, is the gain / phase measurement necessary for TPS62140?

I think the gain/ phase margin will be good with recommended LC combination.

BR.

Stan.

over 7 years ago

0 Chris Glaser over 7 years ago

TI__Guru**** 150950 points

Hi Stan,

If you use an LC within the recommended range in the D/S, it will be stable.

0 Stan Wu over 7 years ago in reply to Chris Glaser

Intellectual 580 points

Hi Chris,

Thanks. If so, does bode plot measurement necessary if we follow the LC range?

Stan.

0 Chris Glaser over 7 years ago in reply to Stan Wu

TI__Guru**** 150950 points

Hi Stan,

No, you don't have to measure the bode plot.

0 Stan Wu over 7 years ago in reply to Chris Glaser

Intellectual 580 points

Hi Chris,

Got it and thanks. We’ve confirmed the ripple/jitter/and transient with 2KHz~50Khz range. We don’t see any unstable waveform or large jitter. And the results all meet criteria and are positive. I believe that we could use these items to make sure the stability of the design is no problem instead of bode plot measurement, correct?

Stan

0 Chris Glaser over 7 years ago in reply to Stan Wu

TI__Guru**** 150950 points

Hi Stan,

Yes, this is the most important item: that you have tested and verified the circuit as sufficient for you application. Yes, transient response can be used to verify stability, as explained here: www.ti.com/.../slva381b.pdf

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TPS62140: Is Gain/phase margin measurement necessary for DCS mode solution?