On the line side, a crowbar protection element is usually chosen to take the initial surge. A crowbar device exhibits a discontinuous IV curve characteristic with a sufficiently high turn on voltage to ensure that the protection element does not interfere with the telephone network ring signal. This approach has one disadvantage inherent to the protection scheme – crowbar elements such as GDTs and thyristors generally allows a relatively large let-through transient to the line driver side of the xDSL circuit. The means that the residual energy will transfer to the line driver side, thus place a higher burden on the line side protection. To address this concern, the protection on the line side must shunt the high frequency portion of the transient quickly enough for ESD and cable discharge and also provide sufficient surge handling to arrest a residual lightning pulse. It is always best to use line side shunt components that provide a robust rating to lighting surge. A device rated for ESD transients only is not sufficient for today’s line driver circuitry.
The RClamp0522T and RClamp0524T are ultra-low capacitance ESDprotection devices that have been optimized for use on next generation serial display inter- faces. Each have a typical capacitance of only 0.30pF between I/O pins and 0.80pF between any I/O pin and ground. This allows it to be used on circuits operat- ing in excess of 3GHz without signal attenuation. They may be used to meet the ESD immunity requirements of IEC 61000-4-2, Level 4 (±15kV air, ±8kV contact discharge). The RClamp0522T is designed to protect two lines, while the RClamp0524T will protect four lines. The RClamp0522T is in a 6-pin, RoHS/WEEE compliant, SLP1610P4T package. It measures 1.6 x 1.0 x 0.40mm. The RClamp0524T is in a 10-pin, RoHS/WEEE compliant, SLP2510P8T package. It measures 2.5 x 1.0 x 0.40mm. The leads are spaced at a pitch of 0.5mm. They are designed for easy PCB layout by allowing the traces to run straight through the device. The leadless design and flow through layout minimizes impedance stubs for maximum signal integrity.
In Section 2, we suggest low-voltage triggering thy- ristor protectiondevice structures assuming usage of standard CMOS processes, and introduce device charac- teristics based on DC device simulations. In Section 3, we briefly explain discharge modes in HBM tests and introduce two input protection scheme utilizing the sug- gested protection devices. In Section 4, we construct an equivalent circuit model for CMOS chips equipped with the input protection devices to simulate various input HBM test situations, and execute mixed-mode transient simulations. Based on the simulation results, we figure out weak modes in real discharge tests, and present in- depth analysis results relating critical characteristics such as peak voltages developed across gate oxides in input buffers, locations of peak temperature inside protection devices, and so on. In Section 5, based on the simulation results, considerations relating device and circuit design are discussed.
Abstract: For three fundamental input-protection schemes suitable for high-frequency CMOS ICs, which utilize protection devices such as NMOS transistors, thyristors, and diodes, we attempt an in-depth compari- son on HBM ESD robustness in terms of lattice heating inside protection devices and peak voltages devel- oped across gate oxides in input buffers, based on DC, mixed-mode transient, and AC analyses utilizing a 2-dimensional device simulator. For this purpose, we construct an equivalent circuit model of input HBM test environments for CMOS chips equipped with input ESDprotection circuits, which allows mixed-mode tran- sient simulations for various HBM test modes. By executing mixed-mode simulations including up to six ac- tive protection devices in a circuit, we attempt a detailed analysis on the problems, which can occur in real tests. In the procedure, we suggest to a recipe to ease the bipolar trigger in the protection devices and figure out that oxide failure in internal circuits is determined by the peak voltage developed in the later stage of dis- charge, which corresponds to the junction breakdown voltage of the NMOS structure residing in the protec- tion devices. We explain strength and weakness of each protection scheme as an input ESDprotection circuit for high-frequency ICs, and suggest valuable guidelines relating design of the protection devices and circuits.
Abstract: For a long time, in the process of mine hoisting system design, the installation position of overwind and overwind protectiondevice is determined according to experience, which is widely disputed, indicating that the system safety has not reached the perfect state, and the traditional experience conclusion needs to be analyzed theoretically. It is necessary to study the parameter matching problem, analyze the impact of overwind protection devices on the system protection results at different installation positions, and improve the safety of the prompt system from a system perspective. The research about parameters matching of overwinding safety protection system of the shaft multi-rope hoisting system has been worked on in this essay by carrying out simulation analysis with numerical methods, involved with specific examples, in the perspective of the dynamics. According to the research, the braking force on the over wind side is significantly greater than that on the under wind side, there is the best matching relation between overwinding and underwinding braking force, making the braking stroke on the overwinding and underwinding side equal, or the overwinding is slightly larger than the underwinding stroke, which will be more beneficial to the safety of the system. The conclusion of this study is helpful to perfect the theory of overwind protection and improve the security of the system.
The ZT13085E transceivers incorporate internal protection structures on all pins to protect against ESD charges encoun- tered during handling and assembly. The driver outputs and receiver inputs have extra protection against static electricity as they are directly interfacing to the outside environment. As such, these pins against ESD of ±15kV without damage in all states of the transceiver's operation in the static state. After multiple ESD events, Zywyn’s ZT13085E transceivers keep working without latchup. These devices eliminate the need for external transient suppressor diodes and the associated high capacitance loading, allowing reliable high-speed data communications.
The integration of a diverse knowledge base under a common user interface poses both a conceptual and a technical challenge. Interoper- ability between data and models raises relatively simple challenges such as units and numerical domain, to highly complex ones such as scale and representation of time, space, and behavior. These issues apply equally to ‘static’ information (data) and ‘dynamic’ information (models). The role of dynamic process information in the ESD is multi- fold. First of all, models of various kinds are necessary for projection of known phenomena, scenario generation and analysis. Patterns of global change and environmental processes can be simulated to analyze the effects of particular deci- sions or decision-making strategies, or to project the consequences of current situations into the future. In addition, support functions such as parameter search, sensitivity analysis, and opti- mization can all be described and included in the database as specialized dynamic content.
Research on reliability of relaying protection in smart substation not only has a positive effect on the rational configuration scheme of relaying protection in smart substation, but also can promote the stability and safety of the over- all operation of power system. There are many reliability strategies for relay- ing protection in smart substation. In practice, the key points of relaying pro- tection should be clarified. Based on the reality, the protection configuration should be strengthened; the voltage limited delay should be used for protec- tion, and the protection configuration scheme of actual lines should be paid attention to, so as to improve the reliability of relaying protection in smart substation and promote the realization of stable and sustainable development of power system and smart substation.
CHD603BM-U is a high-performance Mifare card reader/writer which has standard USB communication interface and with ESD electrostatic protection function, it use for read Mifare card, it mainly use for smart card system especially for background of the card issuer and writer, the characteristics of the product is that have good appearance, quickly response, long distance reading, stable performance, easy for use, needless external power supply, installation of wiring simple and solid, it adopt of a USB virtual serial, and the system software can use it directly without changes.
A second challenge surrounding the response to a DC fault is that it can be difficult to detect and discriminate faults on a DC network . For example, the converter topology used in a DC system architecture can either have a high or low capacitance filter and either be a current limiting or non-current limiting topology . If the converter filter has a high capacitance, then in response to a fault, there will be an initial high peak current, as the capacitor discharges followed by a sustained fault current. It is difficult to coordinate a protection system to discriminate between these two current levels. However, if the converter is current limited and has a low filter capacitance, then there is no fault current source. In this scenario, it is difficult to detect and determine the location of a fault. If a fault is not detected and protection activated quickly enough, then unacceptable consequences of the fault will occur. These include converter voltage reversal and over voltage transients. Another type of fault that induces undesired heat generation is DC partial discharge due to voids or contaminates in the dielectric layer of the distribution cable. Partial discharges are small discharges of pico to nanocoulombs of charge. The resulting current would not exceed the circuit protection fault current magnitude and is difficult to detect. Other difficult to detect faults include a partial, or soft, fault between DC poles. The current may be well within the circuit protection current limits, yet generate damaging localized
3 Afterwards, ESD was installed in a house with single phase house power supply. The installation was done in a house in Melaka. Then, the data were collected through power consumption of daily electrical appliances usage. The value of voltages, currents, real powers and power factors of electrical appliances in the house has recorded by the digital wattmeter and fluke digital multimeter. The data were collected in a week for before and after the installation of the ESD. This study only limited to the effectiveness of the ESD.
Building on these design experiences from existing technologies, identifying D2D candi- dates in a network assisted scheme can be based on the alternatives depicted by Fig. 3. In a-priori schemes, the network (and/or the devices them- selves) detect D2D candidates prior to com- mencing a communication session between the devices (left hand side schemes of Fig. 3). As an extreme approach (upper left), the network does not actively participate in the discovery process other than assigning beacon resources to the devices. Such beacon assignments are broadcast in the coverage area of the cell so that D2D servers (transmitting a beacon) as well as D2D clients (detecting beacons) can readily find one another. According to an alternative approach (lower left) the server first registers to the net- work, and the client willing to engage in D2D communications sends a request to the network (e.g. the serving eNB or other network entity (NWE)). Such registration and request messages may contain other information such as an own identity, a buddy list, or offered/required ser- vices. In this case the NWE takes a more active role in the discovery process mediating between the server and the client and requesting the D2D server to generate the beacon (Step 3 in the lower left scheme).
These machines operate automatically as it is controlled by a microcontroller system and powered by 12 DC power supply. The advantages of Express Sole Dryer (ESD) from the previous floor mat are, it can dry shoe sole without disturbing user movement. Express Sole Dryer (ESD) will rub user shoe sole automatically while user walks on it. It also can remove water automatically that which has already been absorbed by the floor mat.
be involved in their learning processes (Ausubel, 1968; Novak, 1976), and (b) the development of the notion of Emotional Quantity (EQ) as a prerequisite for success at work and in life (Goleman, 1998; McClelland, 1973). The evolvement of new learning theories, alongside with the emergence of EE and later ESD, opened an unofficial entrance to emotional learning. These processes are reflected in EE and ESD literature as well. Posch (1999), in his definition to the term school ecologisation, explained that "Ecologisation means shaping our interaction with the environment in an intellectual, material, spatial, social, and emotional sense, to achieve a lasting/sustainable quality of life for all" (p. 341). Breiting & Mogensen (1999), when referring to the action competence approach to EE, found co-variances between emotional and cognitive aspects that contribute to the formation of action competence among students. Breiting et al. (2005) claimed that in the context of ESD, cognition is not only rational but also emotional and values-based. Mogesen & Mayer (2005) argued that action-taking in a natural environment allows linking emotions to values and to rational thought. The philosopher, Ronald de Sousa (1987), described emotions as a philosophical hub, which leads us to problems of epistemology, ontology, logical form, and ethics. He posed a question, "what would someone be like if he had no faculty of emotions?” De Sousa answered that the faculty of emotions is actually required for the more conventional mechanisms of rationality to function. Emotions, through their role as a hub, also act as motivators for action taking and by thus expressing one's most active self. De Sousa (1987) claimed that "Emotions concern what gives meaning to life; they frame, transform and make sense of our perceptions, thoughts and activities" (p. 2). By this, emotions inherently involve raising questions of values and ethics, which form a central part in any educational effort towards sustainable development.
Having solid modeling and design analysis, such as finite element analysis (FEA), integrated within a single environment means you can evaluate design performance at a much earlier stage and not waiting until you build a prototype for testing. You can review the results used to refine and optimize the design, rather than performing these tasks as a final validation check prior to prototyping and production. You can use the Simulation tools built into SOLIDWORKS Premium to determine the stress, strain, deformed shape, and displacement of components under operational loads or upgrade to even more capable simulation capabilities with SIMULATION Standard, Professional or Premium. Simulation-based design tools allow you to identify problems quickly and inexpensively and then modify your design to address them early in the process when the cost of change is substantially lower. For example, the Drop Test feature in SOLIDWORKS Simulation allows you to determine the effect of impact on the proposed design when someone drops it from various heights. Another example is a company that used SOLIDWORKS Simulation capabilities to evaluate a concept for a needle-free injection system, using integrated analysis to determine the contact pressure and safety factor.
Works. A picture of the design is shown in figure 3.2 Two main parts can be distinguished. One is the main body colored in green. The other is the as- sembly (cyan rods with magenta bars), which presses on the springs (gray) and holds the magnet (blue). There are also two adjustment mechanisms installed. One changes the effective lengths of the springs by adjusting the positions of the little red blocks. By turning screws on the side, the little rim on the red block is moved. Due to the change in effective length, the spring constant is altered (appendix B on page 29). The other mechanism changes the point of engagement of the springs by moving the magenta pressure plates up and down with the nuts.
Abstract: Optical communication uses light to carry information. It does not conduct electricity. This prevents problems with ground loops and conduction of lightning. Optical fiber communication is unaffected by neighboring electromagnetic radiation compared to electrical communication. The optical fiber is electrically non-conductive, so it does not act as an antenna to pick up electromagnetic signals. Purpose of this project is to design an optical device between both the equipment’s and transmission and reception of signals is done using optical communication. Signals from different protocols will be multiplexed before transmission and demultiplexed after reception of signals through optical fiber. Keywords: Optical fibre, optical communication, protocols, multiplex, demultiplex.
In conclusion, we have presented circuits for reducing leakage in a variety of MOS ESD power supply clamps in 0.18µm and 0.13µm processes. The circuits have enabled substantial reduction of leakage without compromising ESD performance. A large payoff in leakage reduction comes with various backgating schemes to reduce the subthreshold leakage of the clamping MOSFETs (PMOS in our case, but the same principles would apply to NMOS). These effects are most pronounced when that subthreshold leakage dominates the total leakage, and are less noticeable when gate oxide leakage is substantial. In addition, stacked voltage-tolerant ESD clamps benefit from improving on the resistive voltage divider as a way to establish internal bias in the clamp. An active circuit targets the bias current distribution in a more efficient way and reduces leakage current in these clamps for all processes, whether or not gate oxide leakage is substantial. Finally, the total charge required for power-up of the supply clamp at ordinary supply ramp rates can be reduced by adding a single resistive element to the circuit, but this has no appreciable effect on the circuit’s behavior at the ESD time scale.
“The protection of ESDS is accomplished by providing a ground path to bring ESD protective materials and personnel to the same electrical potential. All conductor and dissipative items in the enviroment, including personnel, shall be bonded or electrically connected to a known ground or common connection point [EBP earth bonding point]. This connection results in sharing of charge which equalizes the voltage across all items and personnel and eliminates the chances of an ESD event to ESD sensitive devices. Electrostatic protection can be maintained at a potential different from a “zero” voltage ground reference as long as all items in the system are at the same potential.” [CLC/TR 61340-5-2:2008 User guide clause 4.4.1 Grounding/bonding systems Introduction]