Reduce DC Voltage with Resistor Calculator

Voltage Divider Formula:

\[ V_{out} = V_{in} \times \frac{R2}{R1 + R2} \]

Output Voltage (V_out): volts

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1. What is a Voltage Divider Calculator?

Definition: This calculator determines the output voltage of a simple resistor voltage divider circuit.

Purpose: It helps electronics engineers, hobbyists, and students design circuits that reduce DC voltage levels.

2. How Does the Calculator Work?

The calculator uses the voltage divider formula:

\[ V_{out} = V_{in} \times \frac{R2}{R1 + R2} \]

Where:

\( V_{out} \) — Output voltage (volts)
\( V_{in} \) — Input voltage (volts)
\( R1 \) — First resistor (ohms)
\( R2 \) — Second resistor (ohms)

Explanation: The input voltage is divided proportionally based on the ratio of R2 to the total resistance.

3. Importance of Voltage Division

Details: Voltage dividers are fundamental in electronics for creating reference voltages, biasing transistors, and interfacing different voltage level circuits.

4. Using the Calculator

Tips: Enter the input voltage and both resistor values. All values must be > 0. The output will always be less than the input voltage.

5. Frequently Asked Questions (FAQ)

Q1: What's the maximum current through the resistors?
A: Current = V_in/(R1+R2). Ensure resistors can handle the power (P=I²R).

Q2: Can I use this for AC voltage?
A: Yes, but only for instantaneous voltage calculations. For AC, consider reactance.

Q3: What happens if R2 is much larger than R1?
A: V_out approaches V_in (minimal voltage drop).

Q4: What if R1 is much larger than R2?
A: V_out approaches 0 (maximum voltage drop).

Q5: How accurate is this in practice?
A: Accuracy depends on resistor tolerance and load impedance (add buffer for precision).