A digital BIST for opamps embedded in mixed-signal circuits by analysing the transient response

Abstract

A new digital B E T for OAs embedded in mixed-signal circuits is proposed in this paper. During test mode, the transient response of the OA under test shall be measured in order to detect any deviation of the overshoot with respect to the fault-free circuit. The overshoot of the transient response is a very sensitive parameter and can be easily obtained by sampling at a particular time. The analog test stimuli signal can be easily generated by means of a current sink made of a single PMOS transistor. The test decision block is purely digital, with only two TDM comparators, two flip-flops and some logical circuitry just to compare fault-free and CUT two-bit signatures. Simulation results show the effectiveness of the proposed technique with low area overhead.

A TDC Based BIST Scheme for Operational Amplifier

“…The transient response analysis based test techniques are the most feasible for BIST technique. In [3], the Op Amp under test was converted into a voltage follower, and the transient response was analyzed in order to measure the overshoot and slew rate deviation with respect to the fault-free response. However, the parameters of overshoot and slew rate vary among different Op Amps with different architectures, the designed system must be modified to test other Op Amps, even in the same chip.…”

A diagnosis method of analog parts of mixed-signal systems controlled by microcontrollers

“…In addition, the offered BISTs are dedicated only for selected, non-numerous classes of circuits, e.g. : ADC-BIST for analog to digital converters [1][2][3], BISTs for fully differential circuits [4], BISTs based on the oscillation-test methodology for active analog filters [5][6][7], BISTs for opamps [8]. The feature of these BIST, which increases their production costs, is hardware excess.…”