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ESP-Wroom-32 powering

Posted: Thu Dec 27, 2018 12:40 pm
by Kamool
Hello,

I'm building commercial project based on esp32. It uses ESP-wroom-32 module, instrumentation amplifier and one mosfet. ESP32 is in BT mode. It is used in motorcycle so I would like to power it from ignition coils 14.8V. But how?

I've tried using AMS1117-3.3, but that overheats and shuts down.

Other thing was cheap step-down converter from aliexpress. It works, but I don't think that's good idea to use that in comercial product, because it has to comply with RED/EMC.

Any other sugestions how to power up module without using several linear voltage stabilizers?

Re: ESP-Wroom-32 powering

Posted: Fri Dec 28, 2018 7:53 am
by ats3788
I don't have any Problems with the AMS 3.3 maybe you have a wrong resistor or broken C

Re: ESP-Wroom-32 powering

Posted: Fri Dec 28, 2018 2:52 pm
by Kamool
How come You don't have any problems?

When powering from 14.8V to 3.3V at 130mA it has to dissipate almost 1,5W. Isn't that much for SOT-223 package?

I'm using 10uF at both sides.

Even 3.3V regulator in TO-220 package is not enough and overheats..

Re: ESP-Wroom-32 powering

Posted: Fri Dec 28, 2018 9:23 pm
by loboris
Use switching instead of linear regulator :!:

You are building a commercial project and have to ask about how to power it !? :o

Re: ESP-Wroom-32 powering

Posted: Sun Dec 30, 2018 7:53 am
by Kamool
I would use switching regulator if i know how. I've never used them and I'm a little worried about noise emissions.

Are there some guide that would help me to design circuit that will comply with standards?

Re: ESP-Wroom-32 powering

Posted: Sun Dec 30, 2018 10:17 am
by loboris
You can start with a step-down module like this one.
I've used it and it works very good, I don't think you have to worry about noise emission.
Later, if you make your own PCB, you can integrate the circuit on it, the chip used is MP2315.

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