Source: https://guthlabs.ai/docs/instruments/rectifier-dc-power-supply-ripple-calculator/

instrument / verified-clean

# Rectifier/DC Power Supply Ripple Calculator

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Status: **VERIFIED_CLEAN**Lifecycle: **verified-clean**

## Inspectable records

[01**Overview**Purpose and lifecycle](<https://guthlabs.ai/docs/instruments/rectifier-dc-power-supply-ripple-calculator/>)[02**Mechanism**Method and assumptions](<https://guthlabs.ai/docs/instruments/rectifier-dc-power-supply-ripple-calculator/mechanism/>)[03**Implementation**Binding and validation](<https://guthlabs.ai/docs/instruments/rectifier-dc-power-supply-ripple-calculator/implementation/>)[04**Qualification**Evidence and errata](<https://guthlabs.ai/docs/instruments/rectifier-dc-power-supply-ripple-calculator/qualification/>)

## Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

**Area**: Electrical & Electronics Engineering — Circuits, Power Systems, Electronics Lab

**Tranche**: tranche-5

**Evidence ID**: t5-152

**Ledger rows**: 1

No ledger note is attached.

## Review findings

The supplied equations are standard simplified capacitor-input-filter approximations under ideal-diode, constant-current, small-ripple assumptions. Review is required because the transformer-secondary voltage convention, diode-drop treatment, rectifier-type mapping, percentage-ripple definition, and claimed peak/RMS outputs are not fully specified.

### Formula and scope findings

- Vripple≈Iload/(f·C) is the standard constant-load, ideal-capacitor sawtooth approximation, but only when C is in farads, Iload is in amperes, and f is the capacitor recharge frequency.

- Vdc≈Vpeak−Vripple/2 is the standard average-output approximation for a small, approximately linear capacitor discharge, but the specification does not define how Vpeak is obtained from transformer secondary voltage.

- The claimed computation of Peak and RMS is incomplete: no explicit peak-voltage formula is supplied, and no ripple-RMS formula or RMS output definition is supplied.

- The rectifier-type handling is underspecified. Half-wave uses f=line frequency, while both full-wave center-tapped and bridge rectifiers use f=2×line frequency; bridge and center-tapped circuits have different diode-drop and transformer-secondary-voltage interpretations.

- The %ripple formula is not explicitly stated. This review assumes %ripple=100×Vripple_pk-pk/Vdc.

### Unit assumptions

- Transformer secondary voltage is assumed to be RMS AC voltage.

- Vpeak is assumed to be the ideal secondary peak, Vsecondary_RMS×sqrt(2), with no diode-voltage subtraction.

- For a half-wave rectifier, f=line frequency; for full-wave or bridge rectification, f=2×line frequency.

- Capacitance must be converted to farads and load current to amperes.

- The reported Vdc is the approximate average DC output, and ripple voltage is peak-to-peak.

- The calculations assume steady state, constant load current, negligible capacitor ESR, ideal rectifier behavior, and ripple small enough for the linear-discharge approximation.

## Boundary hardening

**BREAK_CLAIMED** · SELF_FLAGGED

Zero filter capacitance makes the ripple denominator vanish, producing an undefined result that requires input rejection. The specification also leaves the transformer-secondary voltage convention unspecified, causing materially different Vpeak, Vdc, and percent-ripple results for the same displayed voltage.

## Errata and corrections

No applied erratum is attached to this unique-name record.

## Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

````
{
  "inputs": {
    "transformer_secondary": "12 VAC RMS",
    "rectifier_type": "half-wave",
    "load_current": "0.50 A",
    "filter_capacitance": "10000 µF",
    "line_frequency": "60 Hz"
  },
  "expected_outputs": {
    "Vpeak_ideal_V": 16.9706,
    "Vdc_V": 16.5539,
    "Vripple_pk_pk_V": 0.8333,
    "percent_ripple": 5.0341
  },
  "working": "C=10000 µF=0.010000 F. For half-wave, f=60 Hz. Vripple=I/(f×C)=0.50/(60×0.010000)=0.50/0.60=0.833333 V peak-to-peak. Vpeak=12×sqrt(2)=12×1.41421356=16.970563 V. Vdc=Vpeak−Vripple/2=16.970563−0.833333/2=16.970563−0.416667=16.553896 V. %ripple=100×0.833333/16.553896=5.0341%."
}
````

## Related workflows

No source-defined multi-instrument workflow membership is recorded.

## Sources and evidence

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

- `VERIFIED_LEDGER.json · VERIFIED_CLEAN`

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

- `BOUNDARY_HAZARD_CATALOG.json`