This book provides readers with a single-source reference to current sensing integrated circuit design. It is written in handbook style, including systematic guidelines and implementation examples. The authors focus on the implementation of wide-bandwidth current sensing on a single microchip, toward usage in applications such as sensing, control and optimization of the energy flow in growth areas like industrial electronics, renewable energies, smart grids, electromobility and the Internet of Things. Provides readers with a comprehensive, all-in-one source for current sensing integrated circuit design, including implementation examples; Discusses modeling and optimization of on-chip Rogowski coil and Hall sensor in both lateral and vertical orientation; Includes noise reduction techniques, such as auto-zeroing and chopping; Covers open-loop and closed-loop sensor front-end design; Presents the first on-chip current sensor with a planar coil placed besides a power line to measure internal signal currents and the first off-chip current sensor with a helix-shaped coil for external signal currents in the multi-MHz region.

High bandwidth sensors are required to measure the wide-bandgap devices’ transient behavior because of their very fast switching speed. In addition to high bandwidth, the current sensor must introduce little disturbance to the switching power loop. Specifically, excessive parasitic inductance introduced by the current sensor drastically changes the switching behavior, making the measurement result invalid. Conventional high bandwidth current sensors are first reviewed to understand their limitations. By combining the structure of coaxial shunt resistor and alumina substrate of surface mount thin film resistors, a novel current sensor surface mount coaxial shunt resistor (SMDCSR) is introduced. Its performance is then modeled and experimentally characterized. Experimental testing verifies its capability of achieving very high bandwidth of up to 2 GHz while introducing little parasitic inductance of less than 0.2 nH. Compared with state-of-the-art commercial products, SMDCSR achieves more than 10x higher bandwidth and less than 1/10 insertion inductance. SMDCSRs are thus ideal for current measurement where high bandwidth and low electrical footprint are required, especially for wide-bandgap devices’ dynamic characterization.

Environmental and chemical sensors in optical fiber sensor technology The nature of the environment in which we live and work, and the precarious state of many aspects of the natural environment, has been a major lesson for scientists over the last few decades. Public awareness of the issues involved is high, and often coupled with a scepticism of the ability of the scientist and engineer to provide an adequate, or even rapid solution to the preservation of the environment before further damage is done, and to achieve this with a mini mum of expenditure. Monitoring of the various aspects of the environment, whether it be external or internal to ourselves and involving chemical, physical or biomedical parameters is an essential process for the well-being of mankind and of the individual. Legis lative requirements set new standards for measurement and control all around us, which must be met by the most appropriate of the technologies available, commensurate with the costs involved. Optical fiber sensor technology has a major part to play in this process, both to complement existing technologies and to promote new solutions to difficult measurement issues. The developments in new sources and detectors covering wider ranges of the electromagnetic spectrum, with higher sensitivity, allow the use of techniques that some time ago would have been considered inappropriate or lacking in sufficient sensitivity.

ABSTRACT: In very deep submicron technologies, supply current testing techniques are essential to achieve high fault coverage and to reduce test length. Due to high supply leakage currents, the quiescent power supply current (IDDQ) testing technique is no longer applicable for deep submicron technologies. However, the transient power supply current (IDDT) testing technique can be used in an environment of high leakage current and offers high fault coverage and reduced test time. A new built-in current sensor is presented here that has the potential to overcome some of the limitations of the other current sensors proposed previously. The current sensor can find application for testing embedded static random access memories (SRAMs) at high frequencies. It employs a high pass filter circuit to eliminate the effects of leakage current and utilizes cascaded high bandwidth amplifiers for high IDDT measurement sensitivity. Open defects in SRAMs are modeled as resistive open defects and studied using the new built-in current sensor for a 0.35 [(mu symbol)m] process technology. The current sensor efficiently detects the open defects in SRAMs that cause transition faults and destructive read-out faults. A two-vector test pattern is suggested with the current sensor for the detection of these faults. The first test vector is used to initialize the SRAM memory cell being tested, and the second test vector is applied to activate the fault.