Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Applied voltage (V)

Voltage applied across the resistor.

Max working voltage (V)

Maximum working voltage of the part.

Check whether the voltage applied across a resistor is within its maximum working voltage rating, which defaults to 250 volts. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Within rating

True when the applied voltage does not exceed the rating.

• Resistor value, power, noise, and color-code calculations must account for tolerance, temperature coefficient, voltage coefficient, pulse rating, working voltage, package thermal resistance, ambient temperature, and mounting. Required steady-state power should include the manufacturer's derating curve.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• Ripple Rating Check

  Compare the ripple current applied to a capacitor against its rated ripple current and report the signed margin percent; negative values mean the rating is exceeded.

• LVDS Swing Check

  Check whether an LVDS differential swing in millivolts falls within the 247 mV to 454 mV specification window.

• Current From Power Rating

  Compute the maximum safe continuous current in milliamps through a resistor from its power rating and resistance using I = sqrt(P/R).