A voltage divider circuit is a simple electronic circuit used to divide a voltage into smaller fractions. It consists of two or more resistors connected in series, with an input voltage applied across the series combination. The output voltage is then taken across one of the resistors or between them. The ratio of the resistance values determines the division of the input voltage into the desired output voltage.
The formula to calculate the output voltage in a voltage divider circuit is:
Vout = Vin * (R2 / (R1 + R2))
Where:
Vout is the output voltage.
Vin is the input voltage.
R1 is the resistance of the first resistor.
R2 is the resistance of the second resistor.
The circuit can be constructed using discrete resistors or potentiometers (variable resistors). Here's how you can construct a basic voltage divider circuit with two resistors:
Choose the resistance values: Decide on the desired output voltage and select appropriate resistor values for R1 and R2. The ratio of R1 and R2 determines the output voltage ratio.
Connect the resistors in series: Place the resistors in series, one after the other, with one end of each resistor connected to the other.
Apply the input voltage: Connect the input voltage (Vin) across the entire series combination of resistors. One end of the input voltage is connected to the first resistor (R1), and the other end is connected to the second resistor (R2).
Measure the output voltage: Measure the output voltage (Vout) across one of the resistors (R2) or between the two resistors (R1 and R2). Depending on your application, you may use a multimeter or an oscilloscope to measure the output voltage.
It's essential to ensure that the resistors you use can handle the power dissipated in the circuit to avoid damaging the components. Also, keep in mind that the voltage divider is a passive circuit, and it might not be suitable for high-power applications due to power dissipation issues in the resistors.
Additionally, the output voltage in a voltage divider circuit is sensitive to changes in load impedance. Therefore, if the load connected to the output changes, the output voltage will vary accordingly. For some applications, buffering the output using an operational amplifier (op-amp) might be necessary to maintain stability and isolate the circuit from load variations.