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.
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?
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?
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.
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?
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?
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.