Optocoupler, optoisolator - either name, the Arduino sends current thru an LED, the light from that drives the base of an output transistor, and that transistor provides control of the other circuit.
Since the control is transferred via light, the 2 sides can have isolated power & grounds.
Now in the case of your camera that could be handy to make sure you isolate the Arduino from the camera. However when you want the pin active (closed) then you will need to drive the LED which will take current (maybe 5 mA). So in a low-power situation it is fine as long as having the opto-coupler not "on" is the desired default state.
Well, I'm assuming that it would send pulses of light to transmit the signal, similar to a TV remote? So how would that benefit me?
Let me ask you this. What would the difference be in using a MOSFET rather than a regular transistor? Either NPN or PNP? What are the benefits of the MOSFET over a transistor?
xKoldFuzionx:
Well, I'm assuming that it would send pulses of light to transmit the signal, similar to a TV remote? So how would that benefit me?Let me ask you this. What would the difference be in using a MOSFET rather than a regular transistor? Either NPN or PNP? What are the benefits of the MOSFET over a transistor?
First the T in MOSFET stands for transistor so both mosfets and BJT are transistors. Main benefit of some mosfets over some BJTs is less heat dissapation for a given current load because of the very low Ron specification you can obtain these days, and that can be a big deal in many applications. In other applications it matters little which you choose.
xKoldFuzionx:
Let me ask you this. What would the difference be in using a MOSFET rather than a regular transistor? Either NPN or PNP? What are the benefits of the MOSFET over a transistor?
Maybe see this concurrent thread: http://forum.arduino.cc/index.php?topic=200444.0
Ok, so BJT it is. That works, as I have a bunch laying around! 