A potential divider circuit is a very common circuit used in electronics where an input voltage has to be converted to another voltage less than it. This circuit is very useful for all analog circuits where variable voltages are required, hence it is important to understand how this circuit works and how to calculate the values of Resistors.

This circuit creates a voltage inversely proportional to a variable resistance.

The basic circuit operates at a frequency determined by R1, R2 and C1 and has a pulse width range of 0 to 100 percent.

The following diagram shows a basic circuit with an open collector output that would require a pull up resistor at its output. The parts values are the nominal values of the components used.