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Im having trouble creating a schematic for 12v input with 3.3v output and 5v output. can someone shine some light. thank you Answered

12 v input

3.3 v and 5 v output

Tags:circuit

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rickharris (author)2018-03-08

i agree with Steve

https://www.electronics-tutorials.ws/blog/variable...

will show you how to use the LM317 regulator. Use 2 and derive both voltages.

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steveastroukBest Answer (author)2018-03-07
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shyxm (author)steveastrouk2018-03-07

around 50mA is fine. The amount of current doesnt really matter for now. Just trying to get the right components and layout etc.. I'll adjust it afterwards.. Thanks so much for your help!

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steveastrouk (author)shyxm2018-03-07

The current level affects greatly the choice of components (and the circuit to be used !)

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shyxm (author)2018-03-07

im trying to implement a buck converter

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steveastrouk (author)shyxm2018-03-07

There is very little point using a buck converter at these very low currents. The simplest method is linear regs like the 7805 and its derivatives. Total device dissipation will be around 0.5W

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shyxm (author)steveastrouk2018-03-07

I can increase the current to 5A. That being said, i dont mind seperating the outputs. Means having two different circuits.

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Josehf Murchison (author)2018-03-07

Yes like Steve said What current, (Amps)?

Just google voltage regulator circuit and there are hundreds of circuit diagrams.

LM317, LM7805, AMS1117 5.0, and AMS1117 3.3, ICs are all 1 amp regulators, LM317 is adjustable from 35 volts down to 1.5, LM7805 is 5 volts, AMS1117 5.0 is 5 volts, and AMS1117 3.3 is a 3.3 volt regulator IC.

If you download the datasheets here:

http://www.maxim4u.com/

The datasheets will have example circuits in them.

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shyxm (author)Josehf Murchison2018-03-07

around 50mA is fine. The amount of current doesnt really matter for now. Just trying to get the right components and layout etc.. I'll adjust it afterwards.. Thanks so much for your help!

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