The Process Capability Analysis report is designed for high volume (hundreds of thousands of units) and deep SPC analysis. The data warehouse pre-aggregates measurements down to a 1 hour resolution (meaning that if you test 100 UUTs within one hour, all measurements will be aggregated into a few calculated values).
The well-known WATS filter is present and you start the report by selecting parameters and applying the filter.
The first result level is a list of Part Numbers matching your filter options. Each record is matching Part Number and Process. The list display Tot# (Unique UUTs tested), FPY# (number of passed UUTs), FPY (First Pass Yield), SPY (Second Pass Yield), TPY (Third Pass Yield), CPK1 (test step with worst CPK value first), wo/F (CPK with step status = PASSED), # (number of step failures). TIP: Hold the mouse over a CPK value to see test step name.
Yield KPI Targets are highlighted:
Red = Alarm
Orange = Warning
Green = Good
(To edit the KPI Targets, browse to Control Panel>Configure/settings>KPI Targets)
Red: CPK < 1.33
Green: 1.33 =< CPK =< 4
Blue: CPK > 4
Select one or several records and Apply Selected. A list with all test steps will be displayed (only test steps returning a numeric value (Numeric Limit Test, Multiple Numeric Limit Test))
The step list shows CPK calculations with and without failures, step yield, total (test) count, mean value, standard deviation, low limit and high limit.
The left margin gives 2 “View Details” options:
Unit View. Presents data from the relation database equal to the detail report view in the Test Step Yield & Analysis report. Can plot every single measurement and drill down on serial numbers (not available if number of units exceed 10K)
- Aggregated View. Presents data from the data warehouse. More usable when large data sets. No serial number details.
The aggregated view shows a zoom able chart where you can select grouping method and different calculation options. When you change grouping, the data will be recalculated based on the selection. It will also list SPC calculations below the chart.
Further, it will list distribution charts for SW filename and version, Revision and Station Name with CPK line.
In the Station Name chart, click on one of the columns to open the same detailed view filtered for that one station (similar to Captains View functionality)