I have a design in progress for an Arduino MIDI interface.
Based on some notes i took last year it uses a 6n136, but when I have breadboarded it the interface does not work.
But substituting the 136 for a 137 does…
I have hunted arround and everything i find says they should be a direct substitution?
Thoughts??
Rob
Have you looked at the datasheets? I see several significant differences such as:
Maximum output supply voltage 7 V (6N137) vs 15 V (6N136)
Output supply current 4, 4.1 mA (6N137) vs 0.01, 150 µA (6N136)
Propagation delay time 48, 50 ns (6N137) vs 200, 200 ns (6N136)
The two are pin compatible but have different output construction.
They might be a direct substitution in some applications but they’re certainly different parts.
I think you can drop in a VO2601 as a like-for-like for the 6N137. I’ve gone the other way, as it was cheaper and easier to get one 6N137, rather than five VO2601.
The dataset that’s linked from the RS page for the VO2601 had details on both the 6N137 and VO2601 - https://docs.rs-online.com/3d4c/0900766b817102db.pdf
I had not read the datasheet no, sorry should have been one of my first ports of call.
It’s only being asked for 5V to drive the RX on a Dunio, but with it on the scope it’s only producing 1.9V at the duino pin and near 5V disconnected so assume it could do with a transistor to drive the pin.
I can live with just using the 137…
Cheer rob
I had to put a pull up resistor on the H11L1 that I was recently messing about with:
Something like that…
can i ask how the 6N138 also differs? i think i read somewhere its too slow for midi or something and that could explain the issue im having with a circuit as it either responds really slow or drops out notes all together
i see, thanks, its probably fast enough for what im using, i only just realized i put some resistors in parallel and not series so that’s probably giving me the issues im having