Appliance Electronics & Control Boards worked example

Functional Test Yield Calculator at 70% target first-pass functional yield: a worked example

This worked example runs the functional test yield calculator numbers for a tougher week than the baseline: 70% target first-pass functional yield instead of the typical 97%. Calculate appliance control board functional test yield from passed boards, tested boards, and the target first-pass yield.

The inputs for this scenario

  • Boards passed functional test: 4,720 boards (held at the documented default)
  • Total appliance boards tested: 5,000 boards (held at the documented default)
  • Target first-pass functional yield: 70 % (the input this scenario stresses; the baseline uses 97)

Working through the calculation

  • The calculation starts from the formula this tool documents: First-pass functional test yield = boards passed functional test ÷ total appliance boards tested × 100.
  • First-pass functional test yield works out to 94.4 % at these inputs, and this is the headline figure for the scenario.
  • Yield gap to target works out to -24.4 points at these inputs.
  • Boards passed functional test works out to 4,720 boards at these inputs.
  • Total appliance boards tested works out to 5,000 boards at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where target first-pass functional yield sits at 97% and the headline result is 94.4 %, this scenario lands almost exactly on the baseline at 94.4 %.
  • Use it at end of shift or end of lot to gauge functional test performance on a control board line and flag when you are drifting under your committed yield. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • First-pass functional test yield: 94.4 % (headline result)
  • Yield gap to target: -24.4 points
  • Boards passed functional test: 4,720 boards
  • Total appliance boards tested: 5,000 boards

Run it with your numbers

  • To rerun this with your own numbers, open the live Functional Test Yield Calculator calculator, set target first-pass functional yield to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.