Test control point insertion and x-bounding for logic built-in self-test (lbist) using observation circuitry

Abstract

Test control point insertion and x-bounding for Logic Built-In Self-Test (LBIST) using observation circuitry. In some embodiments, LBIST circuitry may include a plurality of test control circuits coupled to a scan chain of a Circuit Under Test (CUT), and a plurality of observation circuits coupled to the test control circuits, each of the plurality of observation circuits including one or more latch devices configured to drive a respective one of the plurality of test control circuits. In other embodiments, a method of testing an integrated circuit may include issuing an instruction that a plurality of observation circuits and a plurality of input/output (I/O) control circuits within the integrated circuit enter a test mode, and providing, one or more test patterns to a selected one or more of a plurality of scan chains within the integrated circuit and to each of the plurality of observation circuits.