Re: Opto coupler
... Most of the time opto couplers are used to protect communication lines.
for example, you can use opto couplers to protect your Tx, and Rx lines between your RS232 and PC, from power surge that would be harmful to your PC and RS232 chip.
you must keep in mind that if you attend on using opto coupler as a communication protection scheme, you must pick an opto coupler with fast switching rate, to prevent any corruption in data.
Keep in mind that opto coupler should not be used as a power isolation scheme, if you want to have a power isolation scheme, I would recommend using transformers, TVSs and PTCs. The reason is because opto couplers use diode, thus you have to keep in mind that you do not exceed the diode max. ratings