Voltage Divider Calculator
Calculate output voltage for a resistive voltage divider.
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Enter the input voltage, R1 (connected to input), and R2 (connected to ground). The calculator shows the output voltage, division ratio, and current through the divider.
About Voltage Divider
A voltage divider is one of the most fundamental circuits in electronics. Two resistors in series divide the input voltage according to the formula Vout = Vin x R2 / (R1 + R2). The output voltage is always less than the input. Voltage dividers are used for level shifting, creating reference voltages, biasing active components, and reading sensor outputs. Understanding their limitations (loading effects, power dissipation) is essential for effective circuit design.
Frequently Asked Questions
What is a voltage divider?
A voltage divider uses two resistors in series to produce an output voltage that is a fraction of the input. The output is taken across the second resistor (R2).
When does the voltage divider formula break down?
The formula assumes no load (infinite impedance) at the output. If a load is connected, it acts as a parallel resistance with R2, reducing the output voltage.
What are common uses of voltage dividers?
Level shifting, sensor reading, biasing transistors, creating reference voltages, and measuring high voltages with a voltmeter.