Low cost, high ease photocoupler board

Because of a school projects, which was a battery powered Automated guided vehicle. I found the need for galvanic isolation of a high power and a low power circuit. The high power circuit was connected to a LiPo battery and because of this there was a safety risk. To reduce the safety risk the high power circuit had a circuit breaker and components that could handle a bit more power, then the Arduino and sensors in the low power circuit. When building a photocoupler board on a proto PCB I found that it toke me a bit more time then I expected to build the circuit. Because I think this wouldn’t be the last time I needed to use  a photocoupler board, I thought why not create a simple PCB for it.
So that is why I created the photocoupler board.

The PCB can be found and ordered here. The board uses 5 PC817 Photocouplers, 5 300 Ohm 0805 resistors and 5 1kOhm 0805 resistors. These values are chosen for a 5V input. If you want it to work with higher input voltages the 300 Ohm resistors need to be replaced with higher resistance resistors. In the video you can see that the photocoupler board can easily handle Arduino PWM signals.

Figure 2: Photocoupler board bottom
Figure 2: Photocoupler board bottom
Figure t: Photocoupler board top
Figure 1: Photocoupler board top

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