Power Device & Converter Loss Calculator

Configure a converter, quantify semiconductor loss, and review thermal and rating margin.

LOCAL-FIRST · NO UPLOADS
What it doesModels per-device and converter loss across twelve standard power topologies.
What it needsAn operating point, device data, switching method, and thermal assumptions.
Model boundarySteady-state screening model. Confirm dynamic stress, SOA, and temperature on hardware.
Fast answer · Synchronous buck

Steady-state converter analysis

Enter a generic design operating point, then calculate. All inputs and results remain in this browser session.

Analysis stateREADYReview inputs, then calculate.
Resolved mode—
Output power—
Design check—
READY Review the operating point, then calculate.
MOSFET die loss Calculated — Die dissipation; gate-driver power is separate system consumption
Modeled efficiency Calculated — Based on losses included in the current model.
Maximum Tj Calculated — Iterated RDS(on) thermal estimate
VDS margin Derived — Entered rating minus modeled voltage stress
Topology result Calculated — Available after calculation.
Detailed analysis

Power-device results

Per modeled device
DeviceDutyIpkIrms PcondPswGate (system)TjDie lossCheck
Loss breakdown

Where the power goes

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Advanced analysis

Explore sensitivity and device tradeoffs

Runs only when requested
Visible proof

Topology schematic

Synchronous buck · labeled semiconductor map
IDEALIZED
Click a FET label to highlight its calculated row. Functional power-stage diagram only — not a gate-drive, protection, or PCB-layout schematic.
Visible proof

Calculated waveforms

Ten steady-state switching cycles
Idealized engineering waveforms; parasitic ringing is not simulated. —
Electrical inputs and calculated results exist only in this browser session and are excluded from optional analytics. Engineering estimate — verify against datasheets and measured hardware.
How it works

From operating point to an explainable loss estimate

PowerFET Lab uses standard steady-state converter relationships and user-entered datasheet parameters. It keeps conduction, switching, gate-drive, body-diode, ripple, passive, and thermal estimates visible so each result can be reviewed instead of treated as a black box.

01 · DEFINE

Select the power stage

Choose a recognized converter topology and enter the electrical operating point.

02 · MODEL

Enter component data

Use public MOSFET datasheet values, passive values, switching frequency, and thermal assumptions.

03 · REVIEW

Inspect every result

Compare per-device loss, junction temperature, ripple, waveforms, equations, and design margins.

Topology directory

Standard power-converter stages covered by the calculator

All descriptions and default values are generic educational examples. The calculator contains no company designs, proprietary component databases, customer records, or uploaded documents.

General

PWM

Manual PWM switch

A single switch with user-defined voltage, current, duty cycle, and switching conditions.

DC

Fully-on MOSFET

A continuous-current pass FET model focused on resistance and temperature-dependent conduction loss.

Non-isolated PWM

BUCK

Synchronous buck

A step-down stage with high-side and synchronous low-side MOSFETs.

BOOST

Boost converter

A step-up stage using an inductor, main MOSFET, diode rectifier, and output capacitor.

S-BOOST

Synchronous boost

A boost stage with an actively controlled MOSFET replacing the output rectifier diode.

Isolated PWM

FLY

Flyback

An isolated stored-energy stage with explicit magnetizing current, reflected voltage, and CCM/DCM timing.

FWD

Single-switch Forward

An isolated on-time energy-transfer stage with an output inductor and reset-winding validation.

HB

Half bridge

Two complementary MOSFETs that create a switching midpoint from a DC bus.

FB

Full-bridge PWM

Four switches generating a bipolar differential voltage across a transformer or load.

Resonant

LLC

Full-bridge LLC

A resonant full bridge using an Lr–Cr tank and transformer magnetizing inductance.

CLLC

Dual full-bridge CLLC

A bidirectional isolated resonant stage with primary and secondary active bridges.

AC/DC

PFC

Totem-pole PFC

A bridgeless boost power-factor-correction stage with high- and line-frequency legs.

Independent reference checks

Textbook equations checked against the calculator engine

These simplified cases intentionally disable secondary dynamic effects so a key result can be reproduced directly from the displayed equation. They are separate from the broader topology model regression suite.

PASS means every displayed calculator value is within the stated numerical tolerance of the independently evaluated reference equation. Hardware accuracy still depends on datasheet and measurement quality.
Responsible use

A design-screening tool, not a replacement for validation

Results depend on the entered data and simplified models. Before hardware release, check nonlinear capacitance and switching-energy curves, temperature-dependent parameters, magnetic behavior, SOA, transient thermal impedance, control stability, parasitic ringing, PCB layout, protection behavior, and measured waveforms.

Readable mathematical calculation

Engineering analysis tools

Only parameters used by this topology and switching-loss method are offered. Gate-resistance sweeps require Qgd / gate current.

Run a sweep to find worst modeled loss, minimum modeled efficiency and highest junction temperature.
Tolerance percentages are read from the Tolerances input tab.
RankCandidateDie lossModeled system lossModeled efficiencyMax TjStatus