Is it possible?? Microcontroller based Potentio meter ( Variable resistance) ? URGENT

[0killingsoul0]

Is it possible to make a microcontroller ( say 8051) based potentiometer . ??????????? How????

 

[FoxyRick]

If you really need a digital potentiometer (rather than a variable voltage or current source) then you are best to simply buy a digital potentiometer i.c.

There are a lot to choose from, with interfaces such as SPI, i2c or even just up/down pins. All easy to connect to an 8051.

https://www.analog.com/en/digital-to-analog-converters/digital-potentiometers/products/index.html

https://www.microchip.com/ParamChartSearch/chart.aspx?branchID=11026

 

[alexan_e]

A potentiometer is a very generic requirement, what do you want to control?
Is it a volume control , does it control current or voltage and at what levels, will it be connected as an adjustment pot to another device?

Alex

 

[0killingsoul0]

A potentiometer is a very generic requirement, what do you want to control?
Is it a volume control , does it control current or voltage and at what levels, will it be connected as an adjustment pot to another device?

Alex

Actually i have a dc motor drive circuit which uses a potentiometer to control speed. So in order to control speed through microcontroller i need to replace it with a digital one.

 

[alexan_e]

I'm not sure that you can replace that with a digital pot, digital pots usually have a max voltage limit of 5v.
What is the voltage across the pot in your circuit?

 

[FoxyRick]

Do you have a circuit diagram of the controller?

 

[0killingsoul0]

I'm not sure that you can replace that with a digital pot, digital pots usually have a max voltage limit of 5v.
What is the voltage across the pot in your circuit?

Its about 10 volts

 

[ibrar]

You can use DAC with micro controller to generate analog voltage for that purpose.

 

[FoxyRick]

You can use DAC with micro controller to generate analog voltage for that purpose.

Possibly, but we can't be sure until we know how the potentiometer is used - what the control circuit is.

 

[ibrar]

Possibly, but we can't be sure until we know how the potentiometer is used - what the control circuit is.

You are right but i was saying in general. Final decision is up on circuit design.

 

[doraemon]

Hello!

If you want to control the motor from a micro controller, one good way to do it is to
change the control: control the motor in PWM directly from the micro controller using
a H bridge. I don't know anything about the motor you are using, but just in case, I
made recently a DC motor driver with RS 232 input. It can drive DC motors and also
2-phase steppers. It's for a very small device, so it is unlikely to fit your 10-V application.
Just for info:
http://search.digikey.com/us/en/products/A3901SEJTR-T/620-1159-1-ND/1108988

Search Digiky, you will certainly find a device that fits your needs.

Dora.