I have a regulated power supply with rating 17V@900mA. The LED display is attached to it and consumes maximum current of 600mA @17v. I have to attach ESP12F WiFi module to it which requires 3.3V @ 500mA.

The DC DC converter in the market can solve the purpose, but how reliable they are and can ESP12F sufficiently draw current from it? Is remaining 400mA sufficient to drive DC DC converter?

I am considering this cheap inexpenisve module based on Monolithic Power System's IC MP1584

Any suggestions would be of great help.enter image description here

  • \$\begingroup\$ I don't think the ESP actually needs 500mA. But with a small buck converter you can convert the 17V down to 3V, say you have an efficiency of only 80% you can already have 1.8A at 3V with the 400mA at 17V, that should certainly be sufficient... \$\endgroup\$
    – Douwe66
    Jan 23, 2017 at 11:01
  • 1
    \$\begingroup\$ @Douwe66 The early ESP modules had nasty peak current requirements which caused problems with many pss dimensioned for the mean current. \$\endgroup\$
    – Russell McMahon
    Jan 23, 2017 at 15:05

2 Answers 2


The ESP8266 will use bursts of up to 170mA when transmitting but will average much lower when idle. You should have no problem running the display and the ESP-12F from that power supply.

Detailed power consumption tests for the ESP8266 can be found here: ESP8266 Power Consumption.


In my tests the ESP8266 uses around 70mA under normal operations and spikes of 170 mA. The spikes can be smoothed out with a 1000 uF cap. This video describes the spikes in details https://www.youtube.com/watch?v=6SdyImetbp8

500 mA should be fine.


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