LP2992: PCN Legacy Chip and the New Chip

Shuji Ishiwata

Part Number: LP2992

Tool/software:

Hi All,

I have a question about LP2992.
The PCN has added information about the Legacy Chip and the New Chip.
Will I need to change the design if I change from the Legacy Chip to the New Chip?

The capacitor information for the Legacy Chip says to use a capacitor with a low ESR (5mΩ),
but the New Chip allows up to 1Ω, so I don't think I will need to change the design if I change from the Legacy Chip to the New Chip.
Am I understanding this correctly?

Best Regards,
Ishiwata

4 months ago

0 Alex Davis 4 months ago

TI__Genius 12780 points

Hi Ishiwata,

If your existing design uses a low ESR ceramic capacitor, no changes should be required.

Best Regards,

Alex Davis

0 Shuji Ishiwata 4 months ago in reply to Alex Davis

Mastermind 7845 points

Hi Alex,

Thank you for your reply.
Is there anything else I should be careful of when changing from a legacy chip to a new chip?

Best Regards,
Ishiwata

+1 Alex Davis 4 months ago in reply to Shuji Ishiwata

TI__Genius 12780 points

Hi Ishiwata,

Stability and output capacitor ESR is the main concern we've seen, especially in older designs using electrolytic or tantalum output capacitors with high ESR.

In general, new chip specs will meet or exceed the legacy chip, but some devices will have slightly worse output noise voltage with the new chip than the legacy chip. This is not the case with the LP2992, though.

Best Regards,

Alex Davis

Power management

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LP2992: PCN Legacy Chip and the New Chip