Novel architecture cuts cost and increases speed of boundary-scan digital-pc-board testing
By Dan Strassberg -- EDN, October 30, 2003
Intellitech's PT100 probably looks unlike any pc-board tester you’ve ever seen. It is also unlikely that the compact, rack-mountable system works in quite the same way as any digital-board tester you’re familiar with—even if you compare the low cost (from $9750), highly ex-pandable PT100 with the small group of testers that, like the PT100, are based on the IEEE 1149.1 boundary-scan standard (Picture). What’s more, according to Intellitech, the PT100 is much faster than other boundary-scan-based testers.
Underlying all of those attributes is patent-pending, proprietary technology, behind which is an equation that Intellitech chief executive officer CJ Clark has modestly named Clark’s formula: N=TCP/(U+L–TS–CS), where N is the number of UUTs (units under test) to test in parallel, TCP is the test and configuration time in parallel, U is the handling time to unload the UUT from the tester, L is the handling time to load the UUT onto the tester, TS is the time for tests and diagnostics that must occur sequentially, and CS is the time for configuration that must occur sequentially.
The gist of Clark’s formula is that you can greatly reduce test time if you break a board’s or a device’s scan chains into multiple chains, load the scan-test vectors into the multiple chains in parallel, and run the tests in parallel. The PT100 consists of a 3U-high rack-mountable unit into which you can plug as many as 16 identical scan-test modules. The com-pany ships the basic system with four modules; additional modules cost approximately $1800 each. You can expand the system by daisy-chaining additional 3U-high units.
Intellitech Corp, 1-603-868-7116, www.intellitech.com.
