A New Miniaturized Gas Sensor Based on Zener Diode Network Covered by Metal Oxide

The development of “portable, low cost and low consumption” gas microsensors is one of the strong needs for embedded portable devices in many fields such as public domain. In this paper, a new approach is presented on making, on the same chip, a network of head-to-tail facing PN junctions in order to miniaturize the sensor network and considerably reduce the required power for heating each cell independently. This paper is about recognizing a device that integrates both sensing and self-heating. This first study aims to evaluate the possibilities of this type of diode network for use as a gas sensor. The first part concerns the description of the technological process that is based on a doped polysilicon wafer in which a thin layer of metal oxide (a gallium-doped zinc oxide in our case) is deposited by RF sputtering. An electrical model will be proposed to explain the operation and advantage of this approach. We will show the two types of tests that have been carried out (static and dynamic) as well as the first encouraging results of these electrical characterizations under variable atmospheres.

Development of an H-shaped antenna with FR4 for 1–10 GHz wireless communications

Wireless networking is now central to modern life, and is anticipated to become ever more pervasive. Therefore, there may be several possible uses for combining lightweight fabric antennas. A flexible fabric is used to increase convenience, and the inclusion of antennas in garments ensures they do not have to be hand-held. Wireless deployment, a single-feed and a dual-frequency H-shaped antenna is presented. The transmitting model is used to build the H-shaped antenna. Varying the dual frequency is achieved with the aid of a capacitive range between 3.85 and 1.88 pF and a Zener diode. The operating frequencies for the cellular implementations of the H-shaped antenna are 2.5–4.5 GHz. The configuration of the antenna is built on an 80 mm × 60 mm dielectric by using FR4 epoxy substrate; the scale of the switch dimension is 0.7 mm × 1.4 mm with relative permittivity of 3.68 and the height of the substratum is 1.6 mm. The patch of the planned structure is supplied by a 50 ohm matching impedance co-axial cable. In this research work the proposed antenna structure gain is 8.2 dBi (86%) for wireless devices. Under the current structure, the high and minimal return losses are from –39.05 to –18.68 dB. The highest and lowest Voltage Standing Wave Ratio values of the proposed structure are 1.78 and 1.02, respectively.

Turbine flow meter with increased metrological reliability

Рассматривается турбинный расходомер применяющийся в качестве элемента бортовой системы управления объектов космической, авиационной, судовой техники для контроля расхода рабочих жидкостей, в котором преобразование частоты в напряжение осуществляется путем сглаживания импульсов с постоянной вольт-секундной площадью, формируемых из сигнала магнитоиндукционного преобразователя. Величина площади задается с помощью генератора с кварцевой стабилизацией частоты и прецизионного стабилитрона. Показывается, что функция преобразования расходомера остается неизменной в течение всего срока эксплуатации. Описывается встроенная схема самодиагностики, обеспечивающая автоматизированную проверку метрологической исправности расходомера в процессе эксплуатации. The article considers a turbine flow meter used as an element of the on-board control system of objects of space, aviation, ship equipment to control the flow of working fluids, in which the conversion of frequency into voltage is carried out by smoothing pulses with a constant volt-second area formed from the signal of a magnetic induction converter. The size of the area is set using a crystal oscillator with frequency stabilization and a precision zener diode. It is shown that the conversion function of the flow meter remains unchanged throughout the life of the meter. A built-in self-diagnosis circuit is described, which provides an automated check of the metrological serviceability of the flow meter during operation.

Circuit Model and Analysis of Molded Case Circuit Breaker Interruption Phenomenon

There are complex physical phenomena for the interpretation of a molded case circuit breaker (MCCB) in a distribution system. Most of the studies of MCCB interruption phenomena were conducted with numerical analysis and experiments. This traditional approach may help improve the performance of the MCCB itself, but it is difficult to find connectivity with other systems. In this paper, the circuit model is proposed and the interruption phenomenon of MCCB is analyzed. The interruption of the MCCB is divided into three sections to deal with physical phenomena occurring in each area. A simplified model is proposed considering the characteristics of each section. Based on this model, the circuit model is proposed. To implement the features of each section, the calculation of physical phenomena is carried out, and this is expressed in the circuit model with resistance and zener diode. Comparing the results of the simulation with the experimental results is as follows. For 7-plates (basic state), the error rate is −5.6% in section II and 16.8% in section III. For 1-plate, the error rate is 36.5% in section II and −17.0% in section III. This case shows much difference from the simplified model in this paper, resulting in the largest error rate. The 7-plates and 5-plates cases, which are available in the general MCCB owing to the shortest distance from the arc, represent a relatively small error rate. Using the proposed circuit model, it is expected that the entire system, including the interruption phenomenon, can be interpreted as a single circuit model.

Designing A Zener Diode Using Ag2O(1-X)Zno(X)/Psi Structures Deposited by Laser Induced Plasma Technique

In this paper Zener diode was designed by mixing three mixing ratios of Ag2O(1-x)ZnO(x), where x is 0.5, 0.3, and 0.1, that are deposited on a p-type porous silicon using laser induced plasma technique at room temperature (RT). The results of the Zener diode showed a decrease in knee and Zener voltage when the mixing ratio of Ag2O(1-x)ZnO(x) structure was increased. Nanofilms of 200nm thickness were prepared from pure ZnO and Ag2O as well as Ag2O(1-x)ZnO(x) with three maxing ratios and deposited on glass slides at RT to analyze the structure and optical properties. The structures of Ag2O and Ag2O(1-x)ZnO(x) showed high absorbance in the visible region with redshift in spectra when the mixing ratio was increased, while ZnO had a high absorbance in the ultraviolet region. It is concluded that when the value of x increases the energy gap value for the Ag2O(1-x)ZnO(x) structure decreases.

Lead-Wire-Resistance Compensation Technique Using a Single Zener Diode for Two-Wire Resistance Temperature Detectors (RTDs)

In remote measurement systems, the lead wire resistance of the resistance sensor will produce a large measurement error. In order to ensure the accuracy of remote measurement, a novel lead-wire-resistance compensation technique is proposed, which is suitable for a two-wire resistance temperature detector. By connecting a zener diode in parallel with the resistance temperature detector (RTD) and an interface circuit specially designed for it, the lead-wire-resistance value can be accurately measured by virtue of the constant voltage characteristic of the zener diode when reverse breakdown occurs, and compensation can thereby be made when calculating the resistance of RTD. Through simulation verification and practical circuit testing, when the sensor resistance is in 848–2120 Ω scope and the lead wire resistance is less than 50 Ω, the proposed technology can ensure the measuring error of the sensor resistance within ±1 Ω and the temperature measurement error within ±0.3 °C for RTDs performing 1000 Ω at 0 °C. Therefore, this method is able to accurately compensate the measurement error caused by the lead wire resistance in two-wire RTDsand is suitable for most applications.

Manufacturing Zener diode using ZnO-CuO-ZnO/Si structures deposited laser induced plasma technique

In this paper Zener diode was manufactured using ZnO-CuO-ZnO/Si heterojunction structure that used laser induced plasma technique to prepare the nanofilms. Six samples were prepared with a different number of laser pulses, started with 200 to 600 pulses on ZnO tablet with fixed the number of laser pulses on CuO tablet at 300 pulses. The pulse energy of laser deposited was 900mJ using ZnO tablet and 600mJ using CuO tablet. All prepared films shown good behavior as Zener diode when using porous silicon as substrate.