user70335: I want to switch on/off some AC device using solid state Omron G3MB relay
I know that for magnetic relay there should be transistor and flyback diode, but what about SSR?
Can I connect it directly to arduino digital pin without any transistors and anything else?
In a closer look on special arduino module, we can see some extras. Are they necessary? I want to put solid state relay (not separated module) into my custom PCB, and I'm confused about that extras.


user2881: According to the datasheet there are multiple models.
Some already have an input resistor for the led (in the opto-isolator) inside the package, but some don't. For the ones that don't have a resistor inside, you'd need to add one yourself, to limit the current to around 10mA.
Some models also have a snubber circuit inside the package. The need for this depends on what kind of load is connected (inductive vs. resistive (AFAIK)).
I thinks the green thing, in the picture, is a fuse. On the other side of the SSR you can see and indicator led, transistor, and 3 resistor (one to limit current to the SSR, one to limit the current through the indicator led, and on for the base of the transistor.). They probably use a transistor, because the current for the SSR and the indicator led combined, is to high for certain micro controllers.

70335: <p>I want to switch on/off some AC device using <a href="http://www.omron-russia.com/doc/relay/ssr/g3mb.pdf" rel="nofollow noreferrer">solid state Omron G3MB relay</a>
I know that for magnetic relay there should be transistor and flyback diode, but what about SSR?
Can I connect it directly to arduino digital pin without any transistors and anything else?</p>
<p>In a closer look on special arduino module, we can see some extras. Are they necessary? I want to put solid state relay (not separated module) into my custom PCB, and I'm confused about that extras.</p>
<p><a href="https://i.stack.imgur.com/ZOxbT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZOxbT.png" alt="Arduino module" /></a></p>
 2881: <p>According to the datasheet there are multiple models.</p>
<p>Some already have an input resistor for the led (in the opto-isolator) inside the package, but some don't. For the ones that don't have a resistor inside, you'd <strong>need to add</strong> one yourself, to limit the current to around 10mA.</p>
<p>Some models also have a snubber circuit inside the package. The need for this depends on what kind of load is connected (inductive vs. resistive (AFAIK)).</p>
<p>I thinks the green thing, in the picture, is a fuse. On the other side of the SSR you can see and indicator led, transistor, and 3 resistor (one to limit current to the SSR, one to limit the current through the indicator led, and on for the base of the transistor.). They probably use a transistor, because the current for the SSR and the indicator led combined, is to high for certain micro controllers.</p>
