Tiny, efficient light load switcher

Mike Bisch

Other Parts Discussed in Thread: TPS62120, TPS54040

I need a very tiny regulator, Vin's 25 to 30V , Vout=3.3V, Iout 10 - 100 mA , preferable package like SOT-5, 6 or 8; freq 500 Khz - ??MHz. It's not too difficult to find initial candidates, but the typical load is 10mA and I know many switcher parts are not efficient at such light loads. Typical Vin is 19V and at 10mA => .15W is dissipated which is pushing it for a tiny LDO. I would like to avoid that.

over 14 years ago

0 Chris Glaser over 14 years ago

TI__Guru**** 151140 points

If you could reduce your Vin range to less than 17V or so, then TPS62xxx parts are your best option. Look at the TPS62120 for example. 85% at 15V to 3.3V at 10 mA. We have more devices like it coming out shortly.

For your Vin range, the SWIFT family devices with Eco-mode are your best bet. The TPS54040 would be best and likely give between 40% and 80% efficiency for your load range.

0 JohnTucker over 14 years ago in reply to Chris Glaser

TI__Guru**** 191445 points

I just want to add that the eco-mode threshold of the TPS54040 is extremely difficult to predict. Even at loads down near 10 mA, you may or may not actually be operating in eco-mode.

0 Mike Bisch over 14 years ago in reply to JohnTucker

Intellectual 370 points

Thanks Chris & John - Just what I needed!

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Tiny, efficient light load switcher