Design with Rotary Potentiometer in Cirkit DesignerA rotary potentiometer, often referred to simply as a "pot," is a variable resistor with a knob or dial that can be turned to adjust resistance. It is a passive electronic component that provides a variable resistance, which can be used to control voltage or current in an electronic circuit. Rotary potentiometers are commonly used in applications such as volume control in audio equipment, as a control input for analog signals, and in various other applications where user input is needed to adjust a parameter.
This circuit consists of two 16-channel analog multiplexers, each connected to 16 rotary potentiometers. The potentiometers' wiper terminals are connected to the multiplexer channels, allowing the multiplexers to select and output the analog voltage from any of the potentiometers.
Open Project in Cirkit Designer
This circuit features a Teensy 4.1 microcontroller interfaced with a SparkFun 74HC4051 8-channel multiplexer to read multiple rotary potentiometers. The AMS1117 3.3V voltage regulator provides a stable 3.3V supply to the multiplexer and potentiometers, while electrolytic and ceramic capacitors are used for power supply filtering and stabilization.
Open Project in Cirkit Designer
This circuit uses a 16-channel analog multiplexer to sequentially read the wiper positions of 16 rotary potentiometers. The multiplexer channels the analog signals from the potentiometers to a single output, allowing for efficient monitoring of multiple analog inputs.
Open Project in Cirkit Designer
This circuit features an Arduino UNO used to control the brightness of a red LED based on the position of a rotary potentiometer. The potentiometer's adjustable voltage is read by the Arduino's analog input, and the LED's current is limited by a series resistor.
Open Project in Cirkit Designer| Pin Number | Description |
|---|---|
| 1 | Counter-clockwise terminal (CCW) |
| 2 | Wiper terminal (the adjustable output) |
| 3 | Clockwise terminal (CW) |
Connection: Connect the CCW terminal to the ground and the CW terminal to the supply voltage. The wiper terminal will provide a variable voltage output that ranges between the supply voltage and ground, depending on the position of the knob.
Adjustment: Turning the knob clockwise typically increases the resistance between the wiper and the CCW terminal, and decreases the resistance between the wiper and the CW terminal.
Reading Values: To read the analog value from a potentiometer using a microcontroller like an Arduino, connect the wiper to one of the analog input pins.
// Define the pin connected to the potentiometer wiper
const int potPin = A0;
void setup() {
// Initialize serial communication at 9600 bits per second:
Serial.begin(9600);
}
void loop() {
// Read the value from the potentiometer
int potValue = analogRead(potPin);
// Convert the reading to a voltage assuming a 5V supply
float voltage = potValue * (5.0 / 1023.0);
// Print out the value in volts
Serial.println(voltage);
// Delay for a bit to avoid spamming the serial output
delay(250);
}
Q: Can I use a potentiometer to control the brightness of an LED? A: Yes, you can use a potentiometer to adjust the current through an LED, thereby controlling its brightness. However, ensure that the current does not exceed the LED's maximum rating.
Q: What happens if I reverse the connections to the CW and CCW terminals? A: Reversing these connections will simply reverse the direction in which the resistance increases or decreases when the knob is turned.
Q: How do I choose the right value of potentiometer for my application? A: Consider the voltage and current in your circuit, as well as the desired range of adjustment. Choose a potentiometer with a maximum resistance that allows for the required variation in your application.