Driving a SSR with Digital Pins

Can the Domino drive a Crydon SSR (CMX60D20) with its digital pins? Looks like the SSR will accept 3V inputs, but I have a feeling the current is too much for the digital pins. Looking through the forums I could not find a definitive maximum load for the digital pins.

Gus has this topic nailed already

I wouldn’t personally drive a relay (independent of size) direct from any micro I would use a NPN to drive it…

I won’t risk possible EMF from the circuit its driving … even solid state relays.

But thats my own opinion

Cheers Ian

Thanks for that reference. Very helpful…

This particular SSR has a built-in opto-coupler so I don’t think I’m worried about EMF, but its questionable weather the USBizi can drive it.


I doubt you will have any problems. FEZ will handle it fine.

Note that the datasheet doesn’t say anything about input current but am assuming they did it right and it is so low that it is not important to mention.

I found a data sheet that said the input current was around 8-10 ma at 3.3V