Circuit for Auto Calibration of a Tester Within a Test Program
Original Publication Date: 1985-May-01
Included in the Prior Art Database: 2005-Feb-18
A circuit is disclosed to enable an integrated circuit chip tester to make measurements to an accuracy which is better than the tester design limits. Tester accuracy in existing integrated circuit chip testers is a function of many errors in the signal load and measurement paths. While some of these errors may be adjusted, they cannot be adjusted to a zero value and thus the test system cannot hold a predefined precision for any appreciable length of time. In general, no matter what adjustments are made to the tester electronics, a no better than 10-millivolt tolerance is possible. Since an increasing number of integrated circuit parts require limits where the Å10-millivolt tolerance is over 40% of the limit window, serious yield or quality degradation will occur.