LM22674 LF ripple rejection

Gareth Richards

Other Parts Discussed in Thread: LM22674

I am proposing to use LM22674 in a design with a high degree (10V p-p) of LF (100Hz) ripple - am I correct to assume that because this is low frequency compared to the switching frequency it will have little effect on the 5V output, at around 0.5A?

over 10 years ago

0 Anston Lobo over 10 years ago

TI__Genius 16025 points

Hi Gareth,

It sounds like you are putting a full wave bridge with an undersized bulk aluminium capacitor on the front of LM22674. No issue with this application so long as there is at least 4.7uF of ceramic mounted very close to the input of the IC.

We suggest you breadboard this with an available eval board.

Thanks,

Anston

0 Gareth Richards over 10 years ago in reply to Anston Lobo

Intellectual 490 points

Thanks Anston - yes that is essentially the situation - space restrictions do not allow for good smoothing of the raw AC

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LM22674 LF ripple rejection