# Best approach to power 5v, 10v & 36v in a single circuit?

#### Nanopfrogs

Joined Dec 23, 2017
1
Hi everyone,

I'm designing a circuit for which I need to supply dc 5v, 4A (for a rpi3 and some LEDs), 10v, 800mA (for a dc motor) and 36v, 200mA (for a pump module circuit I need to include).
Ideally, I would love to power this with a charging battery to make it portable, but that may be to much for my league (i.e., hobby/dyi person).
On the other hand, to make things simpler from the beginning, I've thought on using a 36v wall plug-in power supply to directly supply the pump module and two different voltage regulators (one for 5v and other for 10v). I've also considered using a lower power supply (12v), easier to find, and step it up to 36v, a down to 10v and 5v. Looked into dc/dc converters, switching regulators, zener diodes designs, etc. Also looked into battery charger/boost/chuck modules...and in the end I've got lost to what is the best solution to supply these three voltages to my circuit.
Can anyone please give me some hints to what would be the best approach so that I can get back on focus on what components to look for? (if it is even possible to get a "simple" battery powered solution, even better).
Best regards,
Peter

#### -live wire-

Joined Dec 22, 2017
956
If you could plug it into the wall, you could use some transformers, FULL BRIDGE RECTIFIERS, and some capacitors to get the multiple outputs you need. It would help to know how sensitive your components are, and if it needs to be exactly those outputs.

What you could try is getting an inverter circuit to convert your DC batteries into AC, then connect 3 transformers in a series. One with an output of 36V, another with 10V, and the last one with 5V. Then, you could use FBRs, caps, and resistors as needed. 5V at 4A might be difficult to achieve, so maybe do the whole inverter thing for the 36V and 10V appliances, and use some separate batteries for the 5V appliance.

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#### eetech00

Joined Jun 8, 2013
3,418
Hi

Perhaps by changing your choice of components you can simplify the power supply requirements. Maybe a different pump and motor would help.

eT

#### dl324

Joined Mar 30, 2015
15,511
Welcome to AAC!

What is the voltage tolerance of the motor?

What battery voltage and chemistry are you considering?

Without having more information, I'd lean towards a 12V supply and use switching regulators to get 5V and 36V.