A voltage divider circuit is a simple and widely used electronic circuit that divides a voltage into smaller parts based on the values of two resistors connected in series. It is an essential component in various electronic systems and is used for a variety of purposes, such as generating reference voltages, setting bias levels, or providing input voltage scaling.
The voltage divider circuit consists of two resistors, R1 and R2, connected in series across a voltage source (usually a DC voltage). The output voltage, Vout, is taken from the connection point between the two resistors. The relative values of R1 and R2 determine the ratio of the output voltage to the input voltage.
The voltage division ratio is given by the formula:
Vout = Vin * (R2 / (R1 + R2))
where:
Vout is the output voltage.
Vin is the input voltage (the voltage across the whole series resistor combination).
R1 is the resistance value of the first resistor.
R2 is the resistance value of the second resistor.
The voltage divider circuit works based on the principle that the voltage drop across a resistor is proportional to its resistance value. As current flows through the series resistors, the voltage across each resistor is determined by Ohm's law (V = I * R). The sum of the voltage drops across R1 and R2 equals the input voltage (Vin).
It's important to note that the output voltage (Vout) is affected by the total resistance of the two resistors. As a result, the load connected to Vout should have a much higher resistance compared to the total resistance of R1 and R2 to avoid significant loading effects and maintain accurate voltage division.
Voltage divider circuits have numerous applications in electronics, including level shifting, sensor interfacing, setting bias points for transistors, and generating stable reference voltages for analog circuits. However, they have limitations, and the output voltage can be sensitive to changes in load resistance or changes in the input voltage, which might impact the accuracy of certain applications. In such cases, more sophisticated voltage regulation circuits may be used.