Power RF Transmitter with a digital PIN

Using Arduino Networking, Protocols, and Devices
1

Hello all,

in order to save power I want to deactivate a RF Transmitter as long as it is not used.
Is the power supply of an digital PIN of an Arduino strong enough to power the transmitter?
Do I have to disable and enable again the transmitter before and after deactivating it?

Thanks and best greetings :slight_smile:

2

Is the power supply of an digital PIN of an Arduino strong enough to power the transmitter?

Probably not, though you haven't told us what RF transmitter are you using. Powering stuff by connecting it directly to a digital output is usually not a good idea - better approach is to use a MOSFET switch to connect or disconnect the power.

A lot of RF transmitters (RFM69, all the LoRa stuff etc.) also have sleep modes, with only few uA current draw - perhaps you could use that.

3

a fuse is cheap and can be found anywhere. Arduinos are cheap, but not fuse cheap. do not run current through an Arduino.

use the digital pin to control an FET or a MOSFET or an SSR or a relay or an NPN transistor. use that to switch power.

4

Hello,

thanks for your replies!
I have these cheap china RF transmitters, I don't think a sleep mode is possible.

So I will use a MOSFET, as you recommend.

Just one question remaining:
Do I need to "shut down" the RC switch library (some kind of "disable transmit")? Or is it good enough to start it once in the setup?