Boost converter Single cell (1.5V)

Jeff Starkell

Other Parts Discussed in Thread: LMR62421, LMR62014, LMR61428

I have been asked to clean up an audio design that operates from a single AAA battery. The present design relies on a MIC2571-1 boost converter to provide +9V from the battery.

The user is complaining about noise from this converter getting into the audio stream. The MIC2571 operates at 20kHz, and this just seems like a bad idea for an audio circuit.

I don't know the exact current requirements at 9V, but I estimate about 50mA

Any suggestions for a TI boost converter that will operate from 1.2 to 1.5V.

Thanks

over 9 years ago

0 Anston Lobo over 9 years ago

TI__Genius 16025 points

Hi Jeff,

Please check the LMR62014. This switcher regulates at 1.6Mhz and hence will be out of the Audio band. You can also look at LMR62421 for a higher current rating.

Thanks,
Anston

0 Jeff Starkell over 9 years ago in reply to Anston Lobo

Intellectual 480 points

When I attempt to select input voltage of 1.5V, Webbench won't allow anything less than 2.7V

What am I doing wrong?

0 Anston Lobo over 9 years ago in reply to Jeff Starkell

TI__Genius 16025 points

Hi Jeff,

My apologies I completely glossed over the fact you needed 1.5V as a minimum. Use this site to set your parameters and find the device you are looking for:
www.ti.com/.../step-up-boost-converter-products.page;1.2

Webench is accurate in setting 2.7V as a minimum only because it is still in the process of assimilating TI's entire portfolio.

Thanks,
Anston

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

TI__Genius 16025 points

You can use the LMR61428.

0 Jeff Starkell over 9 years ago in reply to Anston Lobo

Intellectual 480 points

It appears that Webbench will not allow me to specify an input voltage of less than 2.5V, even though the part is specified to operate as low as from 1.2V.

0 Anston Lobo over 9 years ago in reply to Jeff Starkell

TI__Genius 16025 points

Hi Jeff,

I've forwarded your question to the Webench team. You can also post in the Webench forum for any additional issues regarding Webench.

Thanks,
Anston

0 Howard Chen-WEBENCH Design Center over 9 years ago in reply to Anston Lobo

TI__Expert 6365 points

Hi Anston,

The device is being updated with simulations and we made some changes which can affected the VinMin designs. I will take a look and hope to make a quick fix.

Power management

Power management forum

Boost converter Single cell (1.5V)