Abstract: In the large-scale mixed analog-digital IC,the key and difficulty is the analog test.The Built-In-Self-Test (BIST) techniques can not only shorten the time consumed on test and verification,but also improve the fault coverage.Therefore,it has been applied in the analog circuits test more and more.In this paper,the traditional analog circuit BIST methods are discussed,and a kind of analog circuit Built-In Self-Test scheme is present,in which the square signal is utilized as the drive source and the fault diagnosis is conducted through comparing the waveform changes of the circuit response outputs.Its structure is simple and easy to be integrated.And the test complexity and cost can be reduced.The simulation results indicate that the circuit tolerance fault can be detected effectively through the designed scheme.It is fit for the BIST of the analog integrated circuit.