I'm new to electronics, so forgive not using official terms.
I want to make a MIDI project with an Arduino (Mega) and want to have 3 MIDI input channels. Currently on my breadboard I use 6N137 optocouplers which seem to work.
However, I also see schematics using a 6N138 or 6N139 optocouplers... Since I'm not so good at reading datasheets, let alone comparing them (since they use somewhat different terminology).
Since I need to use 3, maybe I thought I can use a so called multiple-optocoupler like this 4 channel optocouper
Also I found LTV847
However, is it comparable to a 6N137? And would I still need to use a diode and resistors as in the schematic:http://www.apogeeweb.net/article/25.html
Or should I use a 6N138 or 6N139 or another since the 6N137 has disadvantages?
Or are there even better/more suitable multiple channel optocouplers than the one I found?
(the reason is want to check if I can save some space by using a multi channel optocoupler instead of 3 separate ones, including resistors/diodes etc).