Oscillation built-in self test (OBIST) scheme for functional and structural testing of analog and mixed-signal integrated circuits

TLDR

ADC functional characteristics such as conversion rate, DNL, and INL are considered the most important. The paper proposes an oscillation‑based built‑in self‑test (OBIST) technique for functional and structural testing of analog and mixed‑signal circuits. OBIST employs an ADC as a test vehicle, designs its structure, measures conversion rate, DNL, and INL at each quantization band edge, investigates oversampled sigma‑delta ADCs for structural testing, and evaluates hard and soft faults. Experiments on real‑world successive‑approximation and flash ADCs confirm OBIST’s accuracy for functional testing, and simulations of a 3‑bit flash ADC and sigma‑delta ADCs demonstrate its effectiveness for both functional and structural testing.

Abstract

This paper describes a new built-in self test (BIST) technique suitable for both functional and structural testing of analog and mixed-signal circuits based on the oscillation-test methodology. Analog-to-digital converter (ADC) is used as a test vehicle to demonstrate the capability of the proposed OBIST technique for both functional and structural testing. Design of different parts of OBIST structure is also presented. The ADC conversion rate, differential nonlinearity (DNL) and integral nonlinearity (INL) at each quantization band edge (QBE) are tested as functional parameters. These parameters are considered to be the most important functional characteristics of an ADC. Practical experimentation using real-world successive approximation and flash ADCs confirms the accuracy of OBIST for functional testing of ADCs. Simulation results using a 3-bit flash ADC designed using a CMOS 1.2 /spl mu/m technology are also presented. For structural testing, oversampled sigma-delta ADCs are investigated. Both hard and soft faults are considered and some simulation results are presented.