Potentiometer like component

Question

Okay you might get this a lot around here; I'm trying to figure out the inner workings of this specific potentiometer like component. I want to get my hands on the datasheet or a similar components datasheet.

It is used to change the volume of the device in question. Rolling is infinite in both directions, it has a small click. I tried measuring it's workings with the multi-meter but I'm baffled by its working.

One click in either direction shorts all three pins. The very next click measures a 620ohm between the three pins, along with a 3.2v between pin 3 and 1/2.

I'm a real noob on electrical engineering, never came across something like this.

From left to right, pin 1-3

The silk screen identifier 'SW2' gives a clue that it is a type of switch rather than a potentiometer. — HandyHowie, Mar 13 '19 at 09:37
That's a co-incidence, I just took my mouse apart to clean mine up a bit. It still sticks though. — Baldrickk, Mar 14 '19 at 13:50

score 34 · Accepted Answer · answered Mar 13 '19 at 09:36

34

That's a rotary encoder - not a potentiometer. The encoder pulses are sent to the microcontroller which adjusts the volume of the system.

Figure 1. 2-bit rotary encoder waveforms. The relative phase of the signals indicates clockwise/anti-clockwise rotation and can be used by the controller to count up or down.

Links:

answered Mar 13 '19 at 09:36

Transistor

168,990
12
186
385

Thank you for your detailed explanation. It all made sense now! – Ricardo Snoek Mar 13 '19 at 09:42
1

@RicardoSnoek Does this answer not deserve to be marked as accepted? – Red.Wave Mar 14 '19 at 06:18
It does! Just forgot to mark it :-) – Ricardo Snoek Mar 14 '19 at 15:02

score 12 · Answer 2 · answered Mar 13 '19 at 09:35

12

It's a rotary encoder, rather than a potentiometer. It looks like this may be your part, but you may need to contact them to get a datasheet.

answered Mar 13 '19 at 09:35

Colin

4,499
2
19
33

Potentiometer like component

2 Answers2