Encoder circuit

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Joined Oct 30, 2020
Hi all I’ve purchased a HEDS-9100 encoder https://nz.rs-online.com/web/p/motion-control-sensors/7967878 to replace a low res photo interupt I made. There is little information in the tds as to whether I need any additional componentry to make this run reliably. In the data sheet under recommended operating conditions it has a note alongside load capacitance ‘3.3 kohm pull up resistor’. I’m wondering if this should be included in my circuit somewhere? I was also wondering if the n/c pin needs to be tied to anything and also should the a and b outputs be tied to ground? Thanks for any help

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Joined Apr 24, 2011
Since the '3.3 kohm pull up resistor’ is mentioned under "Recommended Operating Conditions" I would recommend you operate the device with those resistors.

Pins marked "N/C" means literally NO CONNECTION so leave them alone.

The A and B are outputs and should be connected to the inputs to whatever you are using, not ground.

These sensors produce two outputs that contain information as to which direction the interruptor is spinning. If you don't need thst, flip a coin to choose either A or B.