Design and experimental results of a built-in voltage sensor for mixed signal testing

Among test techniques for analog circuits, DC test is one of the simplest methods for BIST application since it is easy to integrate the test pattern generator but also the response analyzer. This paper presents such a technique and focuses on the design and the experimental results obtained with a Built-In Voltage Sensor that corresponds in our proposal to the analyzer module. Since this sensor gives directly a logical value, simple or multiple DC observation points can easily guarantee at low cost a maximal fault coverage detection. Experimental results obtained on an integrated chip validate the efficiency and the simplicity of this technique. Finally, the sensitivity of this sensor to process variations, temperature and power supply is discussed