Calculators / Resistor voltage divider

Resistor voltage divider

State the tolerance you need. It returns the cheapest E-series pair that meets it, then shows the error budget, so you can see whether the resistors were ever the problem.

tune

Requirement

How is the output used?

Source error passes straight through to the output.

Input Voltage V

Source Tolerance ±%

Target Output V

Max Output Tolerance ±%

Worst case must stay inside this band. It is a constraint, not a goal — the solver buys the cheapest parts that meet it.

speed Impedance Envelope

Max Source Impedance kΩ

Max Divider Current µA

Rₜₕ is the ceiling your ADC or FB pin sets; current is your power budget. The solver takes the weakest divider both allow — lower the Rₜₕ ceiling for a stiffer one.

push_pin Resistors — blank = solve for me

Pin R1 kΩ

Pin R2 kΩ

Pin one to fit around a part you already stock; pin both to verify an existing divider. Pinned values are used exactly as entered.

device_hub Load

R_L kΩ

R_L Tolerance ±%

Load Return V

Return Tolerance ±%

0 V = ground. With a load present the divider is sized for it, so the loaded spec governs.

thermostat Thermal Environment

Temp Min °C

Temp Max °C

Resistor TCR ppm/°C

100 = thick film, 25 = thin film, 10 = precision metal film.

Design

—

Worst case gates

—

all corners at once

Statistical (RSS)

—

independent sources

insights Error Budget

Output
—V

Source Impedance (R_th)

—kΩ

R1 ∥ R2

Divider Current

—µA

Dissipation

—mW

R1 / R2

schema Circuit

alt_route What would change this?

troubleshoot Extreme Value Analysis

Output Min

—

worst-case low

Nominal

—

centre value

Output Max

—

worst-case high

— —

Total Spread

—

Corners

—

No-load Output

—

bar_chart Monte Carlo —

Iterations 10000

Yield

—

within spec

Mean

—

Std Dev

—

Min

—

Max

—

3σ Range

—

Run at one temperature corner, not averaged across the range — yield is a manufacturing number, temperature is an operating condition.

Use these values in the editor

Place the divider on a design and the simulation carries on from here.

These tools and articles give theoretical estimates for educational purposes. Real results depend on component tolerances, parasitics and thermal conditions.