Signal-to-Noise Ratio / SINAD / ENOB Calculator mechanism

Model scope

NEEDS_REVIEW because the exact supported conversion direction and the meaning of an input labeled SNR versus SINAD are ambiguous. The stated SINAD-to-ENOB formula is numerically valid under its documented ADC assumptions, but the instrument claims conversions that are not defined by the specification. The honest label should state that it computes approximate ENOB from SINAD in dB unless the missing SNR, THD, and reverse-conversion formulas are added.

• Only ENOB=(SINAD−1.76)/6.02 is specified, so conversion from SNR, THD, or ENOB back to other metrics is not defined.
• The formula is standard only for SINAD expressed in dB and is an ADC full-scale sine-wave approximation; it is not a universal SNR-to-ENOB formula when distortion is significant.
• No formula is provided for combining SNR and THD into SINAD, or for converting SINAD/THD between amplitude-ratio and power-ratio definitions.
• The claimed bidirectional conversion between SNR, SINAD, THD, and ENOB is therefore incomplete.

Units and conventions

• SINAD input is in decibels (dB), not a linear ratio.
• ENOB output is reported in bits and is dimensionless mathematically.
• The constants 1.76 and 6.02 assume the conventional ideal ADC quantization-noise model with a full-scale sine-wave input.
• SNR, SINAD, and THD must have explicitly documented reference and ratio conventions before conversions among them are implemented.

Inspectable vector

One of 4 source-bound review vectors:

{
  "inputs": {
    "SINAD_dB": 1.76
  },
  "expected_outputs": {
    "ENOB_bits": 0
  },
  "working": "ENOB=(SINAD−1.76)/6.02=(1.76−1.76)/6.02=0/6.02=0 bits. Boundary case: SINAD equal to 1.76 dB produces zero ENOB."
}

Failure boundary

BREAK_CLAIMED · SELF_FLAGGED

The only supplied equation defines SINAD-to-ENOB arithmetic. It does not define SNR-to-SINAD, THD-to-SINAD, or any actual formula branches, and it does not specify validation for units or extreme magnitudes. Large finite JavaScript inputs also lose the 1.76 subtraction through floating-point precision.

Other records

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
• BOUNDARY_HAZARD_CATALOG.json