I want to use an Arduino Uno to control the LED light strips, based on the input signal from a robot controller. The robot controller sends a digital signal with "HIGH" of 24 V and "LOW" of 0 V. I have thought of using an optocoupler between the robot controller and the Arduino to reduce the voltage from 24 V to 5 V, suitable for the Arduino pin.
Can I connect the optocoupler's emitter to the Arduino ground?
The LED strips work on 12V DC and at 2000mA. If I power the Arduino with 12V DC power source connected to the DC jack, can I give the power to the LED's also using the V-in pin of the Arduino?
Please look at my circuit and tell me where I went wrong and why?