US Patent 11170867 Test system

A test system is provided that includes a memory test circuit, a memory, an input logic circuit, a bypass circuit, an output logic circuit and a register. The register is operated as a pipeline register of the memory test circuit and the output logic circuit. In a first test mode, the memory test circuit transmits a first test signal to the memory such that the memory outputs a memory output test signal to be stored in the register and further transmitted to the memory test circuit or the output logic circuit to perform test.