How to use 4N27 optocoupler?

Asked Jul 19 '19 at 09:22

Active Jul 24 '19 at 20:47

Viewed 531 times

I was wondering why the 4N27 optocoupler has a pin for base of the phototransistor - and of course how to connect it.

I've usually dealt with PC817 optocouplers and connected them according to the schematic.

Now I want to do the same with 4N27 (pinout on the picture below,) so do I have to leave the base pin floating, or pull down it?

edited Jul 19 '19 at 11:11

JRE

asked Jul 19 '19 at 09:22

Robert Sabljo

3

I guess what you are looking for is here – Raul Rosa Jul 19 '19 at 09:49
2

the base connection allows one to tradeoff excess On current saturation with OFF current rise time. If this makes no sense, ignore the base lead. – Tony Stewart EE75 Jul 19 '19 at 10:31

0 Answers0