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Design >> High-Power Design >> DC DC converter
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Message started by aaron_do on Sep 28^th, 2007, 8:16pm

Title: DC DC converter
Post by aaron_do on Sep 28^th, 2007, 8:16pm

Hi all,

just a general question. Is it possible to design a integrated CMOS DC-DC converter to convert 1.8 V down to around 0.5 V to drive around 2 to 3 mA? If so, what sort of issues (like efficiency) would i run into?

thanks,
Aaron

Title: Re: DC DC converter
Post by Sid on Oct 3^rd, 2007, 3:20pm

Hi,

If you do not mind a ~40% efficiency, a linear regulator will work! But, I am assuming you want more efficiency. The main problem is I think getting an on-chip inductor with low enough losses. However, even making large enough capacitors on-chip will be a challenge. May be you could consider using an off-chip inductor for your Buck converter. Just a few thoughts ...

-Sid

Title: Re: DC DC converter
Post by Eugene on Oct 10^th, 2007, 8:29am

It's been a while since I dabbled in power electronics but I would think the diodes would present another efficiency problem. With a diode drop of 0.5 Volts and a standard buck converter topology, wouldn't the diode loss be a hefty fraction of the power delivered to the load? I think the only way around the diode problem might be to use synchronous rectification or perhaps some cool new topology I'm not aware of.

Comments?