Electronic Components
Diode Power Dissipation Calculator
Diode Power Dissipation provides a checkable estimate of diode loss. It is intended for scenario comparison, not as automatic approval of a component or installation.
Enter values for Diode loss
Keep every entry on the units shown below.
Values this page needs
Keep nominal component markings separate from measured operating values. If operating conditions changed between readings, calculate separate cases.
Convert units once, retain the original reading, and verify the converted magnitude. If you also need capacity remaining, continue with Battery Self-Discharge Calculator.
- Forward voltage
- Default example: 0.8 V. Enter forward voltage in V.
- Average current
- Default example: 5 A. Enter average current in A.
Before accepting the number
An unlabeled assumption can make an otherwise correct result unusable.
Verify sign, scale, and physical meaning before accepting the number.
How the result is calculated
The displayed result follows P = Vf × Iavg. Only Forward voltage and Average current enter the numerical result.
Using the loaded examples gives 4.00 W. Your saved case should identify where each entry came from.
Calculate diode loss from forward voltage and average current. The broader analysis may also use LED Series String Calculator.
Applying the result
Read Diode loss as the outcome of this equation, not as automatic equipment approval. Compare it with minimum, nominal, and worst-case component values.
Save the raw entries before testing another scenario. Continue to MOSFET Conduction Loss Calculator if conduction loss is also needed.
Compare two operating cases
Change Forward voltage from 0.8 V to 0.96 V while preserving the other measurements. The output changes from 4.00 W to 4.80 W.
This isolates one variable; a real system may change several at once.
Practical limits
Reverse recovery can add loss in switching circuits.
The equation does not include bias dependence, ESR, leakage, saturation, and self-heating. Resolve material omissions before selecting a standard size or rating.
Keep nominal component markings separate from measured operating values. MOSFET Switching Loss Calculator covers the related switching loss step.
Before carrying the answer forward
Check the source of average current before calculating. A credible result requires every field to describe the same physical condition and unit basis.
The displayed diode loss should be checked against minimum, nominal, and worst-case component values. Investigate an unexpected magnitude before changing the model or adding margin.
Document any effect handled outside this page, especially parasitics, layout inductance, tolerance stack-up, switching edges, and thermal resistance. That note prevents a later reader from assuming the simple equation covered it.
Before relying on the answer
Why does the field result disagree with this page?
Recheck units and operating state before investigating pulse ratings, frequency behavior, package temperature, and layout.
Can I change several inputs at once?
Change one uncertain entry at a time and preserve the baseline. Use data-sheet values at the intended voltage, current, frequency, and temperature.
What else is required before final selection?
Use the number as one check, then review voltage rating, current rating, dissipation, tolerance, and transient stress.