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.