Source: https://guthlabs.ai/docs/instruments/mosfet-switching-power-loss-estimator/implementation/

instrument implementation / implementation-contract

# MOSFET Switching Power Loss Estimator implementation

A source-bound implementation contract for MOSFET Switching Power Loss Estimator; deployment and executable qualification remain separate.

Status: **VERIFIED_WITH_ERRATA**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-with-binding-errata

**Evidence ID**: t5-177

**Effect**: Computation or source lookup only

## Input and validation requirements

The literal formula accepts negative Iout and produces a negative switching loss instead of rejecting the input or applying a reverse-current model. Extreme magnitudes can also produce Infinity in ordinary JavaScript evaluation, and unlabeled resistance/time units can change the result by orders of magnitude.

## Required corrections

````
[
  {
    "vector": 1,
    "field": "conduction_loss_W / total_loss_W",
    "wrong": "0.0768 / 2.7648",
    "correct": "0.768 / 3.456",
    "cause": "64×0.012 written as 0.0768 (10× low); switching loss correct"
  }
]
````

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "RDS_on_ohm": 0.012,
    "Irms_A": 8,
    "Vin_V": 48,
    "Iout_A": 8,
    "tr_s": 3e-8,
    "tf_s": 4e-8,
    "fsw_Hz": 200000
  },
  "expected_outputs": {
    "conduction_loss_W": 0.0768,
    "switching_loss_W": 2.688,
    "total_loss_W": 2.7648
  },
  "working": "Pcond = Irms²×RDS(on) = 8²×0.012 = 64×0.012 = 0.0768 W.\\ntr+tf = 0.00000003+0.00000004 = 0.00000007 s.\\nPsw = 0.5×48×8×0.00000007×200000 = 192×0.014 = 2.688 W.\\nPtotal = 0.0768+2.688 = 2.7648 W."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/mosfet-switching-power-loss-estimator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/mosfet-switching-power-loss-estimator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/mosfet-switching-power-loss-estimator/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`

- `tranche errata record`