potentiometer and led

[riboli]

hello
I have a problem I would like to include in the volume control a strip of LED indicators
I have to take a potentiometer with 3 outputs, or can I use a stereo one ?

Thanks to all

 

[Enzo]

Do you want the LEDs to simply tell you where the knob is pointed or do you want them to indicate the signal level?

 

[maxshark]

Do you want the LEDs to simply tell you where the knob is pointed or do you want them to indicate the signal level?

I do think he means to indicate pot position.

Riboli, you may think to combine two pots linking shafts instead of one dedicated ( maybe one stereo of good quality and one poor for led strips ? )

Never tried but it could works !

 

[riboli]

I want to indicate the position.

My idea was to use a pot with 3 outputs, 2 for audio and one for the position but it's hard for me to find it.

then I thought about using stereo potentiometer for volume and also for the position by entering an offset to the signal of +5 V and using two filters to send the audio signals (to the amplifier) and continues for the position (to the uC ) .. .

you think it will work or is a bad idea?

thanks roberto

 

[DigitalJunkie]

A 3 section pot might be hard to find,perhaps a 4 section pot would be easier? Maybe a second pot linked mechanically,
Use a LM391x IC,then you can choose between bar or dot mode.

 

[Mooly]

It's a bad idea to pass DC through a pot that's carrying audio... it makes them very noisy as you turn them.

No easy way... you could mix a low distortion HF signal (100khz say) with the audio and use a notch filter to recover the HF and then fectify and use that to drive a level indicator.

 

[riboli]

I understand... I think I will use a pot with 4 outputs and the LM3914 IC or
I found this component PGA2311PA Datasheet - +/-5V Stereo Audio Volume Control PGA2311PA so in the future will also insert a remote control

thanks!

 

[maxshark]

Maybe a second pot linked mechanically,

Exactly as i suggested.

I think that the main advantage is to use a very good pot for analog volume and a poor ( read cheap ) for the visualization function.

Dunno about quality of double stereo pots ( and costs )

Riboli, I also thought to do a thing as you want to do, in my case mechanical link is a must cause i use a stepped attenuator instead of pot 🙂