Best practice - logging test data to WATS

In these article you will find best practices for WATS logging.

UUT ID - Mandatory fields

Serial Number

The serial number, in combination with the part number uniquely identifies the tested unit. This means that two different parts may share serial number provided that their part numbers are different.

Never use a static serial for repeat/reference/calibration testing as WATS will stop processing KPI's for a unit in a process after 100 retests. In cases where you want to do a repeat test or a test with "no" serial number, a unique serial should be generated using for example today's date and or a running number.

Part Number

The part number identifies the type of product, and can be accompanied with a more readable Product Name that can be configured in the Product Manager.

Test Operation (Process)

The Test Operation, also in some cases referred to as process identifies the stage/type of test performed. WATS will give one set of yield metrics for each process. To best be able to review your yield data in WATS we advise you use generic process names that can be shared across different products and production lines.

Start date/time

The start date/time determines the order of runs. 

These four properties should always be present in any UUT report. Creating a UUT report that matches an existing report on all these parameters will always result in a overwrite/update of the existing report.

Illegal characters

Throughout WATS, wildcards are available for filtering. Using any of these wildcard characters in your UUT fields may cause unwanted behaviour in your filtering.

Avoid these characters in Serial Number, Part Number, Revision, Station Name and preferably in any other field you might want to filter for.

• * or %: Zero or more characters
• ? or _:  Any character at given position
• []:  The character at given position must be within defined range and/or list of characters
• [^]: The character at given position must NOT be within range and/or list of characters
• !: Exclude filter value.
• / or \