Help with open collector encoder.

[kotopuz]

Dear all.
I got things with small motor. Now i moved to 500w. Accidently I've dropped encoder. After that I position readings are unpredictable. Looks like encoders are very gentle devices. Now I found another with open collector. I cant make it work. Please advise. Tried to connect it to 5 volts. Looks like I can measure voltage across power plus and output. Nothing from gnd to A or B. Should I add some resistor? Type is omron e6b2-Cwz6C

[misan]

The more info you provide, the higher the chances you can get help.

We do not know:

• what processor are you using?
• what is the code you are running? (are pull-ups enabled in encoder inputs?)
• how are you connecting the encoder to the circuit?
• when describing your problem, more info is better ("I can't make it work" is not very specific).

That said, a couple of 4K7 resistors from A and B to +5 (assuming that is the voltage of your microcontroller) won't hurt.

[kotopuz]

Finally I found how to fix it. I was very very lucky that encoder can run at 5 volts which simplifies a lot solution. I've connected 0 and 5 volts to ESP32 Vin and GND. A and B as per sketch. Trick was to use build in pullup resistors. It means pinMode(encoder0PinA, INPUT_PULLUP );
pinMode(encoder0PinB, INPUT_PULLUP );

Reason is because open collector only connect output to ground, when it's not connected it's floating and pull up to 5V changes floating to TTL level of 5 volts.
If I use 24 VDC as power I need to make voltage divider.
Now everything works and I have working ESP32 with Blynk interface to jog from mobile phone!
Thanks!

[misan]

You're welcome. If using external pull-ups with ESP, please remember to connect them to 3V3, not to 5V.