potential divider

A potential divider is a resistor or a chain of resistors connected in series in an electrical circuit. It is used to obtain a known fraction of the total voltage across the whole resistor or chain. When a variable resistor, or potentiometer, is used as a potential divider, the output voltage can be varied continuously by sliding a contact along the resistor. Devices like this are used in electronic equipment to to vary volume, tone, and brightness control.

Two resistors connected in series in an electrical circuit in order to obtain a fraction of the potential difference, or voltage, across the battery or electrical source. The potential difference is divided across the two resistors in direct proportion to their resistances.

If the input voltage is Vin volts and the resistors have resistances of R1 and R2 ohms, then the output voltage Vout, or fraction of the potential difference across the first resistor, is given by the equation: Vout = Vin(R1/ (R1 + R2)) When a variable resistor, or potentiometer, is used as a potential divider, the output voltage can be varied continuously from zero to the value of the input voltage by sliding a contact along the resistor. Devices like this are used in electronic equipment as the variable controls for functions such as volume, tone, and brightness control.