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5v regulated but with more current?

Simple question:

Is there a simple cheap upgrade to the good ol' 7805? I need the standard 5v but all of walter's extra boards (i.e. LCD backlights) are starting to get close to, if not over, that 1 amp that the 7805 has to give. I would assume I would never need more than 2, maybe 3 amps.

DC-DC thingies maybe?

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Back in the days of TTL, each sub-circuit had its own regulator. It was very easy for a few chips to require 1 amp. This also helped reduce noise.

You might be able to do something similar. Remember, to tie the grounds together, and have filter caps on each regulator. And go with the low-drop-out regulators.

 Myc 

I found that the premade units that can handle that kind of current or more were usually quite expensive. That's why I made my own. Once I perfect the heatsinking, it will handle up to 5A

Careful with the 7805's and a 7.2 volt battery.

The 7805's need about a 2 volt "overhead" to work correctly (check spec sheet). If your battery voltage drops under load, then you will lose the regulation.

You may want tio find a low drop out regulator. I'm not sure if one exists for the higher amps. 

Myc 

What about using multiple 5 v regs? 1 thats splits off the smaller componenets, then the other that would be used for the higher power components?

I think the 3 amp 7805 will be just fine. I'm only coming down from 7.2V so we're not talkin' much here. I will check out the other links too --free education just reading data sheets, ya know! --I'm such a dork...

 

 

...Did you ever know that you're my hero?

Switchers are the way to go for higher currents.  This part is easy to use:

http://www.national.com/pf/LM/LM25576.html

LM350's will also give you 3A in a linear regulator. 

CTG,

Check your Digikey or Mouser catalog, there are 3 amp version of the 7805 avaialible.  I have one in my old Commodore 1541 Disk drive.

But at 3 amps you may want a swticher. The 78xx's are not that efficient and turn the excess voltage into heat. 

Myc 

I've been using this for 2A and less:

http://www.nteinc.com/specs/1900to1999/pdf/nte1934.pdf

They were about $5 at my local electronics shop.  Use a good heatsink!