I'm wondering if someone could explain why a solid state relay has a minimum voltage that it can switch on or off. For example I'm hoping to use an SSR-10DD (http://www.fotek.com.hk/solid/SSR-3.htm) solid state relay, however the spec sheet mentions a minimum of 5V on the output side. I was hoping to use it to switch around 3V. Why would it require a minimum of 5V?
- V_input range = 5V from an Arduino output pin
- I_Output current range = Signal only, so less than 10ma
- Target load type = Signal
- Reason for isolation = want to avoid all possibility of damaging existing circuit
More details about what I'm trying to achive can be found in this question: Connect Arduino to existing circuit with seperate power supply