Ohm's Law states that Voltage = Current * Resistance (V = I * R), foundational to electrical circuit analysis.

Can I use a voltage divider to power a motor?

No! Voltage dividers are intended for reference signals (ADCs, logic level shifting). Heavy load currents cause significant voltage drops.

How do I choose R1 and R2 values?

Choose values large enough to minimize quiescent current draw, but small enough that input impedance of the receiving circuit doesn't distort the signal.

Back to Calculators

General & Scientific Calculators● INSTANT WASM ENGINE

Electronics Voltage Divider & Ohm’s Law Calculator

Design resistive voltage divider circuits, calculate precise output voltage ($V_{out}$), circuit current ($I$), and thermal power dissipation in Watts.

Input Parameters

Input Voltage (V_in)

Resistor R1 (Ohms)

Resistor R2 (Ohms)

Output Voltage (V_out) Instant

3.84 V

Divider Ratio: 0.320 | Current: 0.82 mA

Proportional Breakdown100% Total

Voltage Drop Across R1:8.16 V

Output Voltage across R2:3.84 V

Analytical Summary

Total Series Resistance14.70 kΩ

Quiescent Loop Current0.816 mA

R1 Power Dissipation6.7 mW

R2 Power Dissipation3.1 mW

Mathematical Formula & Methodology

Underlying equations and mathematical logic governing this engine

Step 01

Voltage Divider Equation

V_out = V_in * [R2 / (R1 + R2)]

Fractional voltage drop across resistor R2.

Step 02

Circuit Loop Current (Ohm's Law)

I = V_in / (R1 + R2)

Total quiescent current flowing through the series divider.

Step 03

Power Dissipation

P = I² * R

Verify thermal load stays within resistor wattage ratings (e.g. 1/4W).

How to Use This Calculator

Supply Input Rail Voltage

Common logic levels include 3.3V, 5V, 12V, and 24V.

Select Standard E24/E96 Resistors

Higher resistance values reduce idle battery drain.

Check Power Dissipation

Ensure heat dissipation does not exceed component wattage ratings.