Arduino pro micro 3.3V 8Mhz + NRF24 Any external AVR recommendation

[BigOlive]

Hello,

I have been using NRF24 modules with Arduino Uno for a long time, powering the NRF24 through a small DC5V-DC3.3V YL-105 regulator connected to the +5V pin of the Uno. This setup works perfectly.

For a new project, I am using an Arduino Pro Micro 3.3V 8MHz, and the NRF24 needs to be powered separately.

I have performed several tests:

• Using an LM2596 regulator set to +5V to power the Arduino (RAW pin) and the YL-105.
• Using an LM2596 regulator set to +3.3V to power the NRF24 module directly, with a separate +5V regulator for the Arduino.

However, the radio.isChipConnected() command always returns NO.

The entire project is powered by a 12V DC 6Ah battery, and all grounds are properly connected.

Do you have any recommendations for a reliable 3.3V power supply for the NRF24?
I also suspect that the timing of power delivery might be an issue. Should the NRF24 be powered before the Arduino? Since I also use the USB port to monitor the serial output, the Arduino Micro might power up before the NRF24...

Thank you for your advice and support.

[jim-p]

If you are using the nRF24 without the PA, you can power it from the pro micro Vcc output which is 3.3V

[JCA34F]

Why not regulate the main 12V down to 3.3V for the NrF?

[BigOlive]

Hello, I will use the NRF with radio.setPALevel( RF24_PA_MAX ) so I need a external regulator.
I already tried to regulate the main 12V down to 5V with LM2596 regulator and they use YL-105 to get consistent 3.3V but the radio.isChipConnected() command returns NO .

Do you have any recommendation of regulator (from 12V to 3.3V) to be used to power the NRF?
Many thanks for your support

[PaulRB]

As already suggested by @JCA34F , adjust your LM2596 to output 3.3V and power the nRF and the Pro Micro through their Vcc pins.

[JCA34F]

I would use something like this or similar to power Arduino AND NrF:
https://www.pololu.com/product/4891