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RC switch with Low-Side MOSFET

First time user, confused about wiring up this device seeking assistance to switch ON 5 volt supply to activate a sound card then turn it OFF when sound has played.


If you have not already, I strongly recommend reading the appropriate sections of the Pololu RC Switch User’s Guide (available on the product page under the “Resources” tab) so you can fully understand how your board works. For the RC Switch with Small Low-Side MOSFET, the appropriate sections are 3, 7, 8, and 9, including all the subsections of those.

If you are just trying to control the power to your sound card with an signal from your receiver, then all you should need to do is follow the typical wiring diagram figure to connect your power supply to the pins labeled “load power supply” and connect your sound card’s power input wires to the pins labeled “load”. You also need to supply logic power which must be 2.5–5.5V. If your RC receiver operates with something in that range, then an easy way you could supply logic power is by bridging the VCC=VCR jumper on the bottom side of the board.

You are welcome to post some pictures of your setup once you think you have it wired correctly and I can double check it for you. Please make sure to also include some pictures that show all of your soldered connections.

By the way, it sounds like you might want the switch to disconnect power to your sound card automatically after it has finished playing; can you confirm whether that is correct? That type of behavior is most likely not going to be possible with just this board, but maybe if you provide the datasheet for your sound card or a link to where you got it I might be able to suggest an alternative approach.

- Patrick

Hello Patrick,
Thank you for your detailed reply.
As you alluded to, the sound card does NOT stop playing and I do want to stop it with another pulse.
Just for your interest the sound card is a Train Horn on one of my garden railway locomotives.
So when I want the Loco to blow it’s Horn, I switch the pulse ON, then when I want the Horn to cease sounding, I switch the pulse OFF.

Having read through all the data sheets you have mentioned I realise that this device may not be what I was hoping for.
I have other techniques for enabling this to be switched ON or OFF.


A96010.pdf (32.2 KB)

Just a reminder, this is a public forum, so please do not post personal contact information. I edited your post to remove that.

I am sorry to hear that the RC switch was not what you were expecting, but I’m glad you know that now so you can hopefully move on to something that will work. Good luck.

- Patrick