WEBENCH® Tools/LMR23615-Q1: Simulation does not have enough phase margin

Jared Becker

Genius 11845 points

Part Number: LMR23615-Q1

Tool/software: WEBENCH® Design Tools

Hi Team,

I am trying to use WEBENCH to simulated the LMR23615-Q1 under the following conditions:

Input: 20V - 28V

Vout: 5V

Iout: 500mA

For some reason, the simulation is telling me there is not enough phase margin. Though, I don't think the conditions above are that drastic to be causing instability. Can you please take a look and help me understand why there is not enough phase margin?

Thank you,

Jared

over 6 years ago

0 Amod Vaze over 6 years ago

TI__Mastermind 26800 points

Hi Jared,

I am able to reproduce your issue. This is a bug in the tool and we will fix this and let you know of when to expect a fix.

Regards,
Amod

0 Jared Becker over 6 years ago in reply to Amod Vaze

TI__Genius 11845 points

Hi Amod,

I am also seeing a similar issue with the same input voltage spec, but with the Vout changed to 8V @ 100mA output current. Can you please check out that one too?

Thank you,
Jared

0 Mahantesh Chanagoudar over 6 years ago in reply to Jared Becker

TI__Intellectual 1045 points

Hi Jared,

We are able to reproduce your issue. We are looking into these issues and you can expect the fix to be on ti.com by 4th week of April.

Thank you,

Best Regards,
Mahantesh

0 Mahantesh Chanagoudar over 6 years ago in reply to Mahantesh Chanagoudar

TI__Intellectual 1045 points

Hi Jared,

The phase margin issue is resolved and fix is available on ti.com now. Please note that Cff is not there on schematic but present in BOM (so design is fine and it is just a schematic display issue) and we have fixed this issue and this fix will be available in next release.

Best Regards,

Mahantesh

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WEBENCH® Tools/LMR23615-Q1: Simulation does not have enough phase margin