BUILT IN ANALOG TESTABILITY
Original Publication Date: 1992-May-01
Included in the Prior Art Database: 2001-Dec-31
While built in testability is common place in digital integrated circuits, this issue has not been explored in the analog arena. In the case of analog VLSI circuits valuable test time is lost before it is determined that the device has failed the test. The more complex the device, the more di&ult it is to characterize the failure and its location in the signal path. To circumvent this problem analog designers use probe pads to monitor critical bias voltages/currents and even signals at probe, before mak- ing AC measurements in order to screen out defective devices in a shorter time. This method however, has several disadvantages: a. Extra silicon is needed for probe pads and cir- cuits to drive the test probe b. Drive circuitry dissipates too much power c. The increase in probe pads also reduces test relia- bility because of additional circuitry and probe needles.