A built-in multi-mode stimuli generator for analogue and mixed-signal testing

Among other applications, programmable oscillators are used to generate patterns for analogue and mixed-signal built-in self-test. The switched-capacitor multi-mode stimuli generator presented in this work associates programmability with lower area overheads. The type of signal (pulse, ramp or sinewave), the amplitude and the frequency of oscillation can be easily programmed. The stimuli generator is expected to alleviate surface penalties, because digital programming of the oscillation frequency can be achieved by changing the switching frequency using an embedded frequency divider. Experimental results involving a biquad filter show that a very high fault coverage can be obtained in both transient and multifrequency modes of the stimuli generator