ESP12 12v converter

Hi Everyone,

I'm looking for a way to convert DC 12v to 3.3v for a new ESP project. All components will be added to a PCB.
The module will be placed in my car, so the input voltage will be 12v.

I don't have much knowledge about power requirements for electronics, so I did some reading.
At first I looked into the AMS1117 which is quite frequently being used with ESPs, but some people pointed out that it's not a good choice when the input voltage is much higher than the output voltage. It would waste a lot of power and create a lot of heat.

A Buck converter would be much better it seems, so I looked around and found two candidates.
One of them is the [AP1509-33]( inc._ap1509-1163839.pdf) which is very small and SMD. I like that a lot, but it does require an additional heat sink and capacitors.
As I want to keep the PCB as simple as possible the other option might be better. It's the TSR 1-2433.

Can anyone recommend either of these two, or maybe some other DC converter?
Also would I need additional capacitors on the input and output side of the converter?


I use this DC 12v 24v to 5v Step Down Converter Regulator 5A 25W Power Adapter Reducer for Car Electronics Truck Vehicle Boat Solar System (Accept DC 8-40V Inputs) to run my RPi in my car and I run 2 ESP32's and other electronics on my weather station.

I use, on the weather station a MCP1700 to bring the 5V down to 3.3V, which is used for the ESP32's power.

Works great last a long time.

Thanks Idahowalker, appreciate the answer!

I'm looking for something that can be put on a PCB though. Maybe I should have added that in my post. I'll edit it.

In all my bare ESP-12 module projects (usually 24volt in) I use the D24V5F3 from Pololu.
With an additional 470uF/6.3volt tantalum cap on the 3.3volt rail, to bridge the ~400mA transmit current spikes.

Chips like the MPM3610, used on the Nano Every etc., could be interesting if you want a bare smd part.

I have decided to go with the AP1509-33
It requires some extra components on the PCB. I think below setup should work.

  • The Diode on the left is not required. This line is 12v.
  • The TP2 on the far right is a pad to test the connection. Also not required.
  • C1 and C2 are 470uF

Sources I used:

I'll post the results when I receive the PCB.

After some testing the AP1509 seems to work perfectly.
It takes some space on the PCB but works well and doesn't get hot, even without a heat sink.
Can recommend it for anyone who needs to convert 12v to 3.3v.

This switching converter at Digikey also works well.

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.