I don't think it does, but I had to ask... see attachment.
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As pointed out in post #6.I understand about CW and CCW and orientation. Let me be more specific. Do both ends and the wiper need to be connected or just one end and the wiper. I have encountered the argument before dealing with pots to adjust LCD backlight and it was stated that only the + to one end of the pot and the wiper to the device needed connecting. Is this valid (it obviously works) and are there any problems doing that? Or even connecting the wiper to + and one end to the device. I wouldn't think so, but am I missing something?
BINGO! That's the answer I needed. Now I understand why both ends are connected. Thank you!In two of the circuits you have a dangling part of the potentiometer that will act like a noise antenna. Is that a difference that matters?
If, in your four schematic, the wiper moves upward with CW rotation, then resistance decreases in #1 and #2, and increases in #3 and #4. It depends entirely on how you connect the device. Hint: an industry standard convention for normal pots and trimpots is that pin 1 is the CCW end, pin 2 is the wiper, and pin 3 is the CW end. If you add pin numbers (or CW and CCW) notations to the two end pins, it is more clear what happens when the wiper turns each way.I understand about CW and CCW and orientation although I thought CW was supposed to increase resistance.
In a perfect world, just one end. But ...Do both ends and the wiper need to be connected or just one end and the wiper.
Ahhh… Another good reason that I didn't consider. Thanks.IF shock or vibration causes the wiper to bounce and momentarily lose contact with the resistive element
OR IF a particulate contaminant gets inside and the wiper loses contact
THEN the impedance at the wiper node jumps to infinity.
Except digipots, but I can program for that. Don't see log pots much anymore. 50+ years ago I built an electronic slide rule using log pots and a beat frequency oscillator. Not very accurate compared to my 12" K&E, but a fun little project. That was before pocket calculators and it was nowhere near pocket size.not all potentiometers are linear, by design
What about audio taper pots? Another name for log pots. They are necessary in audio circuits for volume setting.Except digipots, but I can program for that. Don't see log pots much anymore. 50+ years ago I built an electronic slide rule using log pots and a beat frequency oscillator. Not very accurate compared to my 12" K&E, but a fun little project. That was before pocket calculators and it was nowhere near pocket size.
It was just a quickie schematic for demo purposes, not something I would use. I have learned to protect against low resistance. Most audio has gone digital so the log pot is becoming scarce (is that the word I want?). I tend to use linear pots (usually a trimmer) as a voltage divider to tweak a timer circuit or to control LED brightness.I do not like to see that in all four of your schematics the pots short the V1 power supply, then each pot smokes and burns when its resistance is turned down vey low. None of your pots are used as an adjustable potentiometer(DC or volume control), they are just shown as a shorting rheostat.
I mentioned that several posts back and it has been diligently ignored. Except to say that nobody uses them any more. Folks need to keep in mind that the real world is all analog and not as linear as many would wish.What about audio taper pots? Another name for log pots. They are necessary in audio circuits for volume setting.
Maxim, Analog Devices, et al.Except digipots,
Neat! thanks for the heads up. That's quite a bit more than the 3 wire control 8 pin dips I'm used to.Maxim, Analog Devices, et al.
https://www.maximintegrated.com/en/...onverters/digital-potentiometers/MAX5456.html
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