I need a good relay for an Arduino project. Here are the requirements:
-It needs to be solid-state.
-It needs to be responsive and switch quickly.
-It cannot require too much current or require more than 5V on the input, as the Arduino I am using is incapable of delivering that. The less voltage and the less current needed, the better.
-It must have very low power losses on the outputs.
-It must be able to handle 2 amps at 31 volts, but ideally higher because of tolerances and component life.
-It would ideally have a normally closed pin as well as a normally open one.
-It should be under $20.
-It cannot be too hard to connect to my circuit (no very small pins close together), or too large.

If someone could suggest a good relay that fits the requirements, that would be great. Also, if I am asking too much of a solid-state relay, then please let me know and suggest an alternative.

 

Do you require electrical isolation?

 

A 2n7000 with a SPDT Dip relay on the drain.
Or switch the DIP relay direct.
Max.

 

This is why God invented the parametric search.

https://www.mouser.com/Optoelectron...s/_/N-6x5ji?Keyword=solid+state+relay&FS=True

But you should also define what you are trying to do. There may be a better way other than a solid states relay.

 

Thank you. That was helpful. But how do I search for one that has a normally closed pin and a normally open one?

 

You will likely need two relays. But again post your need there maybe be a better way to do this.

 

If the loads are separate, can you use a logic level N & P Mosfet?
Max.

 

Hello,

The largest solid state (optomos) no/nc I could find is 1 Arms at 60 Volts.

Bertus

 

What is the switching rate? Have you considered a conventional thru hole relay? Very reliable and tolerant.

 

Using two relays instead would not be a problem, but I don't want it to be too expensive. So what are some good, reliable relays that I could use for my project?

 

Using two relays instead would not be a problem, but I don't want it to be too expensive. So what are some good, reliable relays that I could use for my project?

What are the drive characteristics of the Arduino and what is the power budget for the relay?

 

It is an arduino uno and it will have a maximum of 31V at 2.5 Amps on the load side.

 

Hello,

Looking at the arduino uno specs: DC Current per I/O Pin 20 mA.
https://store.arduino.cc/arduino-uno-rev3
Look at the specs tab.

Bertus

 

Using two relays instead would not be a problem, but I don't want it to be too expensive. So what are some good, reliable relays that I could use for my project?

Do you want it good or do you want it cheap??

I am perplexed as why you refuse to mention what you are trying to actually do. You might not even need relays at all.

 

how fast and how frequent switching you need?

 

Is up to 1 or 2 megahertz realistic, or should I look for an alternative? There are multiple things I want to do with the arduino and the 31V power supply, some of which would require fast switching speeds.

 

Is up to 1 or 2 megahertz realistic, or should I look for an alternative?

What type of load are you planning to switch at that speed?

 

SSR are faster than electromechanical relays but even so, 1-2MHz is unrealistic. operating times for 2A SSR are on the order of 1ms meaning that frequencies over 1kHz are going to be unlikely. to get to 1MHz, we are talking about three orders of magnitude.