MC33063A: To achieve higher current output - higher than 1.5 Amps

Atul Bhakay

Genius 3205 points

Part Number: MC33063A

Hi,
i want to use MC33063A in a step down DC to DC application.

My input voltage is from 19V to 30VDC and required output is 5V at 3 amps.

By connecting a transistor driver at the output of the normal step down schematic, can I achieve my aim of 3 amps ?

Regards

Atul Bhakay

over 8 years ago

0 JohnTucker over 8 years ago

TI__Guru**** 191445 points

Maybe, but why not use a device that is deigned to provide 3 A output? There are many possible solutions. I suggest you try Webench to filter fr parts that meet your requirements. Please follow this link:

webench.ti.com/.../webench5.cgi

0 Atul Bhakay over 8 years ago in reply to JohnTucker

Genius 3205 points

Hi,

Thanks for your reply. The advantage of MC33063A is that it is a low cost device. The other parts available for higher currents , like the TPS series are more costly than MC33063A + a transistor !!

Kindly advise

Regards

Atul Bhakay

0 JohnTucker over 8 years ago in reply to Atul Bhakay

TI__Guru**** 191445 points

I do not support MC33063A directly. Let me see if I can find someone to help you.

0 Michael J Schultis over 8 years ago in reply to JohnTucker

TI__Mastermind 24985 points

Hello Atul,

Yes, if you use an external transistor that can handle the 3A that you are referring to, then you can use the MC33063A device as a controller for the circuit.
If you refer to Figure 6 in the datasheet it shows how you should configure the device to handle higher currents.

In this setup, the device itself doesn't ever see the 3A current, so as long as your external switch can handle the peak currents, then you should be able to design this device for that condition.

Best,
Michael

0 Atul Bhakay over 8 years ago in reply to Michael J Schultis

Genius 3205 points

Hi Michael,

Thanks for your reply

Yes, my question has been answered

Regards

Atul Bhakay

Power management

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MC33063A: To achieve higher current output - higher than 1.5 Amps