In-system test of chips in functional systems

Manufacturers perform tests on chips before the chips are shipped to customers. However, defects can occur on a chip after the manufacturer testing and when the chips are used in a system or device. The defects can occur due to aging or the environment in which the chip is employed and can be critical; especially when the chips are used in systems such as autonomous vehicles. To verify the structural integrity of the IC during the lifetime of the product, an in-system test (IST) is disclosed. The IST enables self-testing mechanisms for an IC in working systems. The IST mechanisms provide structural testing of the ICs when in a functional system and at a manufacturer's level of testing. Unlike ATE tests that are running on a separate environment, the IST provides the ability to go from a functional world view to a test mode.