Source: https://guthlabs.ai/docs/instruments/zener-diode-regulator-design-calculator/implementation/

instrument implementation / implementation-contract

# Zener Diode Regulator Design Calculator implementation

A source-bound implementation contract for Zener Diode Regulator Design Calculator; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**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-clean

**Evidence ID**: t5-144

**Effect**: Computation or source lookup only

## Input and validation requirements

The model produces undefined results when Izmin+Iload=0 and produces negative, physically invalid resistance and power when Vin<Vz or when a signed-current convention is used without explicit handling.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

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

````
{
  "inputs": {
    "Vin_min_V": 12,
    "Vin_max_V": 15,
    "Vz_V": 5.1,
    "Iload_min_A": 0,
    "Iload_max_A": 0.02,
    "Izmin_A": 0.005,
    "Pz_max_W": 0.5
  },
  "expected_outputs": {
    "R_ohm": 276,
    "resistor_dissipation_max_W": 0.3551,
    "zener_dissipation_max_W": 0.1829,
    "zener_power_check": "PASS"
  },
  "working": "R=(12−5.1)/(0.005+0.020)=6.9/0.025=276 ohm. At maximum input, resistor dissipation=(15−5.1)^2/276=9.9^2/276=98.01/276=0.3551 W. At maximum input and zero load, Iz=(15−5.1)/276−0=9.9/276=0.03587 A. Pz=5.1×0.03587=0.1829 W. Since 0.1829≤0.5, the Zener check passes."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/zener-diode-regulator-design-calculator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/zener-diode-regulator-design-calculator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/zener-diode-regulator-design-calculator/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`