Voltage divider facts for kids

A potentiometer, pictured here, is a variable-strength resistor.

In electronics, a voltage divider is a simple electrical circuit. It takes an input voltage and creates a smaller output voltage from it. You can think of it like a "voltage splitter." Voltage dividers are also known as resistor dividers or potential dividers.

Most voltage dividers are made from two resistors connected in a series. Sometimes, they can be made from a single potentiometer, which is a special type of resistor that you can change. The output voltage depends on the values of the parts used. If you connect something to the divider, the voltage might change a little.

How Voltage Dividers Work

Imagine you have a big slice of pizza, and you want to share it equally with a friend. You cut it in half. A voltage divider does something similar with electricity. It takes a certain amount of electrical "push" (voltage) and divides it into smaller pushes.

• It usually has two resistors connected one after the other.
• The original voltage goes across both resistors.
• The output voltage is taken from the point between the two resistors.
• The size of the output voltage depends on the size of the second resistor compared to the total size of both resistors.

This setup allows you to get exactly the voltage you need for different parts of an electronic device.

Why We Use Voltage Dividers

Voltage dividers are super useful in many electronic gadgets. Here are a few ways they are used:

• Adjusting Volume: In radios or music players, a voltage divider helps control how loud the sound is. When you turn the volume knob, you are often changing a voltage divider.
• Dimming Lights: Some light dimmers use a voltage divider to control the brightness of a light bulb.
• Sensors: Many sensors, like those that measure light or temperature, use a voltage divider. As the light or temperature changes, the sensor's resistance changes, which then changes the output voltage of the divider. This voltage can then tell a computer how much light or heat there is.
• Battery Monitors: They can be used to check the voltage of a battery. If a battery has a high voltage, a divider can lower it to a safe level for a measuring device.

Potentiometers as Dividers

A potentiometer is a special kind of resistor. You can turn a knob or slide a lever to change its resistance. Because of this, a potentiometer can act like a variable voltage divider.

• It has three connections.
• The full input voltage goes across the two outer connections.
• The middle connection acts like the "output" point of the divider.
• When you turn the knob, you change where the middle connection is "tapped" along the resistor. This changes the ratio of the resistance, which in turn changes the output voltage.

This is exactly how volume knobs on stereos or brightness controls on some screens work!

Images for kids

• 

  High voltage (HV) resistor divider probe. The high voltage to be measured (VIN) is applied to the corona ball probe tip. Ground is connected to the other end of the divider using the black cable. The divider output (VOUT) comes out on the connector next to the cable.

See also

In Spanish: Divisor de tensión para niños