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Lately, built-in self-test (BIST) has been of great importance in the manufacture of very large scale integration (VLSI) circuits. Most BIST schemes compress the test response into a compact signature using space and/or time compaction. A fundamental problem associated with response compaction is error masking or aliasing. In this paper, an alternative zero-aliasing test response evaluation scheme for BIST is presented. The main conceptual ingredient utilized to build the proposed scheme is the application of the Berlekamp–Massey algorithm (BMA). The BMA provides a general solution for synthesizing the shortest linear feedback shift register (LFSR) capable of generating a given finite sequence. Basically, on the BIST design stage and considering the fault-free test response sequence, the BMA is used to synthesize an LFSR capable of generating this sequence in an economical way. The BIST testing stage consists in comparing the obtained test response sequence of the circuit under test (CUT) with the fault-free test response sequence generated by the LFSR previously designed. This way, a testing of the CUT can be made. It is observed that there is no aliasing using the proposed scheme. The key to make this scheme attractive is to keep the LFSR length as small as possible. Based on it, two derived schemes, called Simple-LFSR and Multi-LFSR, are shown to try to solve this problem. Experimental results are shown for some ISCAS85 benchmarks. [ABSTRACT FROM PUBLISHER]

In this paper, a survey on the characteristics of thermoresistive sensors [positive temperature coefficient (PTC) and negative temperature coefficient (NTC)] and their applications to measurement structures that use the electric equivalence principle, in special radiometers and anemometers, is presented. The dynamic responses of the architectures and the influence of the operational amplifier offset voltage on the instrument performance are discussed. Alternative architectures employing pulsewidth modulation (PWM) and sigma-delta analog-to-digital (A/D) converters are also shown. [ABSTRACT FROM AUTHOR]

The performance of a hot-wire anemometer configuration is affected by variation in the fluid temperature The classical temperature compensation techniques in such anemometers employ two sensors. The performance of a temperature-compensated hot-wire anemometer configuration using a single sensor alternating between two Operating temperature and proposed for constant fluid velocity is investigated under conditions of time-varying fluid velocity. The measurement error introduced is quantified and can be practically eliminated using low-pass digital filter. [ABSTRACT FROM AUTHOR]

Programmable analog signal conditioning Circuits can be programmed in the field to permit their use in several applications with a variety of sensors with different output signal characteristics. The digital programming of the gain and dc level shift of a conditioning circuit can affect the measurement resolution and cause a reduction in the range of the measuring system in which it is employed. For a specified maximum acceptable loss in the measurement resolution, a procedure for defining and employing the programming values that guarantees the full measurement range is proposed. The proposed methodology takes into account practical implementation considerations and can be employed for designing either discrete or integrated circuits. [ABSTRACT FROM AUTHOR]