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.

RMS drain current (A)

Required number input.

RDS(on) (ohm)

Required number input.

Compute MOSFET conduction loss as the square of RMS drain current times RDS(on). 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]

Conduction loss (W)

The resulting conduction loss returned as a number.

• MOSFET threshold voltage is not a recommended fully-on gate voltage. Conduction and switching loss depend on gate drive, charge plateaus, current, drain voltage, switching speed, temperature, package parasitics, reverse recovery, dead time, and thermal conditions.
• 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.

• Power Module Loss Conduction

  Estimate resistive power-module conduction loss as RMS current squared times hot on-state resistance; use the operating-temperature resistance.

• Diode Conduction Loss

  Compute diode conduction loss as forward voltage times average forward current.

• ESR Power Loss

  Compute capacitor ESR power dissipation as RMS ripple current squared times equivalent series resistance.