How to Put a Potentiometer on a Digital System
- 1). Connect the supply voltage to the right-hand terminal of the potentiometer, and connect the left-hand terminal to the ground on your device.
- 2). Connect the center terminal of the potentiometer, called the "wiper," to an input pin of the analog-digital converter. Consult the chip's datasheet, available free online from the manufacturer or dealer, for the pin descriptions, diagrams and other useful information. If you're using the potentiometer with a digital system based on a microcontroller, you may not need a separate ADC chip. Many microcontrollers include a built-in ADC, so consult your microcontroller's datasheet to see which pins are connected to an ADC.
- 3). Connect the supply voltage and ground pins of the ADC chip to the circuit power and ground.
- 4). Set the measurement range of the ADC by connecting the upper limit reference pin to the supply voltage and the lower limit reference pin to the ground. Again, there are thousands of different ADC chips available in a wide variety of configurations, so consult your chip's datasheet for specifics. If you're using a microcontroller with an integrated ADC, it may automatically use the microcontroller's power and ground connections as the reference, in which case you can skip this step.
- 5). Connect the output of the ADC to wherever you need the data in your digital system, and program the system to use the data. For example, you could connect the output to a digital input pin on a microcontroller. You'll need to program the microcontroller to communicate with the ADC and read the input before you can use the data in a program. The ADC chip's datasheet will tell you what pins it uses to communicate, and how to read it.
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