What type of voltage division?

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I need to make a voltage regulator to regulate 12V. Obviously I need to divide that down so I can monitor it. I saw a circuit in a magazine once that used an op amp with a gain of 1/10 to do the dividing. Does this simply sound like a good excuse for a tutorial on op amps, or would the op amp somehow work better than a simple voltage divider?

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A simple resistor divider will normally suffice. If your are talking of monitoring the voltage with the ADC on a mega.

Keep it simple it will not bite as hard

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Yes. Automotive voltage regulator, ADC on Mega8.

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I've done it often. I'd recommend a potential divider (2 resistors), filtered with a cap in parallel with the resistor that goes to ground. I'd also parallel a TVS with the cap (i.e. ADC input to ground), just to take care of any nasty 40V+ spikes that can occur in a 12V automotive system.

george.

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paramax - check out this site.

http://www.cruzers.com/~ludis/sc...

See how Delco did this. I reverse-engineered one of these boxes 15 years ago and disassembled the code. I learnt heaps of tricks - this box has so much redundancy. It is a lesson on smart design of a ECU. You'd be pushing to get an AVR to beat it - simply because it had specific hardware for EFI functions, the AVR would out-perform the cpu itself.

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Kartman - that's a cool site. An Amazing amount of work there in reverse-engineering the boxes back to schematics. Not to mention the code.

Dean 94TT
"Life is just one damn thing after another" Elbert Hubbard (1856 - 1915)

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If only I had the internet when I did my reverse-engineering. I stumbled across this site a few years ago - it was interesting to compare my scribbles of the schematic with the ones one the site.

I would suggest anyone undertaking the design of anything look at what is similar -even if it means reverse engineering it. Its no use solving the same problems over again if someone has solved it before, and probably better than what you could do yourself.

It answers a lot of the 'How do I???' questions.