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I'm in the process of building wheel encoders for my robot and have come across 2 different IR Reflectance sensors.

I'm trying to find out what the potential benefits or drawbacks of each one would be and what I should use for my project.

With the digital one, I presume I will receive a HIGH/LOW reading but I will have no way to adjust the thresholds. Would this eliminate noise as mentioned in this answer?

With the analog one, will I have more control over what's supposed to be HIGH/LOW? Are there benefits to going the analog way and handling the signal through code?

At the moment I'm inclined towards purchasing the digital one for the sake of simplicity but I'd love to hear what you have to say on the matter.

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I've used both of them, and I like the analog ones more.

The reason is that with IR, there can be a significant amount of 'stray light' coming from the environment. If you have an analog sensor, you can adjust your thresholds and baselines to tune the sensor to your operation (you have a lot of flexibility). When I used it, I would take 100 readings when I turned the device on, use that as the baseline.

With the digital ones - you're stuck if it's triggering and you don't want it to (you need to physically shield the sensor).

They do use the same sensor in both of the devices, they just change how the phototransistor operates (cap+resistor for the digital version, just a resistor for the analog version), so if you really wanted to, you could change the operation of the sensor (if you have the right resistors and caps).

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If it's for an encoder, then use the digital one. If all you need to sense is each aperture or dark/light pattern in the wheel, then all you need is a high/low signal.
The analog version would be more suited for things like distance sensing (e.g. voltage rises as surface gets nearer) or gradual changes in surface reflectivity.

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