LM3481: boost regulator

ikon

Other Parts Discussed in Thread: LM3481

Hi Support,

If customer use LM3481 as a boost regulator (instead of SEPIC, more complex). Is the circuit still work stable if Vin = Vout?

This condition happen when user plug in a 12V adapter, but the original source is from 2 Li battery in series, around 8.4V.

Thanks.

over 9 years ago

0 Anston Lobo over 9 years ago

TI__Genius 16025 points

Hi Shaun,

I've forwarded your question to the apps engineer. We'll get back to you soon.

Thanks,
Anston

0 Brani Dubocanin over 9 years ago in reply to Anston Lobo

TI__Expert 4100 points

Hi Shaun,
Yes, you can use LM3481 in standard boost configuration in a case as described above.
The part should not become unstable.
However when Vin~Vout in standard boost configuration you will see larger ripple on the output., since device will be hitting minimum on time limitation.
Regards
Brani

0 ikon over 9 years ago in reply to Brani Dubocanin

Genius 5355 points

Hi Brani,

Understand from other boost converter... when hitting the Ton(min), the operating will be pulse skipping at light load and cause audible noise when OVP kick in. It needs careful design and it might not be a good idea to run at Ton(min).

Could you advise?

Thanks.

0 Brani Dubocanin over 9 years ago in reply to ikon

TI__Expert 4100 points

Hi Shaun,

Yes, your understanding is correct.

But again, I want to point out that it is OK to use LM3481 with Vin~Vout condition. Customer needs only to be aware that there will be somewhat higher ripple on the output, but part will not be unstable.

Best regards
Brani

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LM3481: boost regulator