CP Testing

Untested Die Cost: Assembly + FT Test Cost: CP Test Cost (Total): CP Yield (%): ATE Yield after CP (%):

Raw cost =

Add CP test if ATE-only yield is below: %

CP testing calculator help

Fields and assumptions

CP means chip probe; FT means final test; ATE means automated test equipment. Use the same currency and per-die basis for all costs: Untested Die Cost (D), Assembly + FT Test Cost (A), and CP Test Cost (C). Despite the “Total” label, CP cost is added to each untested die in this model; divide a batch total by the number of dies first.

CP Yield is the percentage passing probe (p). ATE Yield after CP is the percentage of those passing final test (q). Enter yields from above 0 to 100%; zero yields cause division by zero.

Formulas

Raw cost per good unit X = ((D + C) ÷ p + A) ÷ q
ATE-only break-even yield (%) = (D + A) ÷ X × 100

In the formula, p and q are decimal yields (90% = 0.90). The threshold is rounded up to the next 0.1 percentage point; raw cost is displayed to two decimals. The comparison assumes the same die and assembly costs without CP and does not include other overhead.

Example

D = 2, A = 0.50, C = 0.10, CP Yield = 90, ATE Yield = 95 → raw cost 2.98, threshold 83.9%. CP is cheaper in this model when the ATE-only yield is below the unrounded break-even threshold (about 83.82%).

Calculator help v1.0