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Wearable Electronics
Published in Muhammad Mustafa Hussain, Nazek El-Atab, Handbook of Flexible and Stretchable Electronics, 2019
Sherjeel M. Khan, Muhammad Mustafa Hussain
A circuit board, commonly referred to as printed circuit board (PCB), is the substrate that holds the electronic components on insulating material and connects the components to each other using electrically conductive metal tracks. A flexible circuit board is very similar to a rigid circuit board where the only difference is that the substrate is now flexible instead of being rigid. The metal interconnects are inherently flexible as their thickness is less than 500 µm. This allows the circuit board to possess any shape provided it stays within the bending limits of the substrate material. In previous subsections, we have discussed the flexibility of all the components in a wearable, and their integration on a flexible circuit board can help us envision a fully compliant wearable system. Commercial companies like Flexible Circuit© Technologies are dedicated to making flexible circuit boards for companies in need of making a flexible wearable device. The circuit boards need to be tested for performance under long term bending conditions.
Electric Circuits and Components
Published in Quamrul H. Mazumder, Introduction to Engineering, 2018
When a voltage is applied using a battery across a conductive wire, electrons flow from the negative terminal to the positive terminal of the battery due to the phenomenon that opposite charges attract. This flow of electrons is termed as current. Note that, even though electrons flow from the negative to positive polarity of the battery, direction of current in the circuit is always shown from higher potential to lower potential. The current-carrying conductor creates an electric field that, when applied across a capacitor, reaches right across the insulating material of the capacitor and traps charge. As a quick refresher, a capacitor is an electronic component that is used to store charge when connected to a voltage source. It is made of two metal plates separated by a dielectric material, as shown in Figure 8.2a. Four different types of capacitors have been mentioned in Section 8.2, and they are categorized using the type of dielectric material used in manufacturing. The ability to store electric charge is known as capacitance.
Allotropic Carbon-Based Nanomaterials
Published in Wesley C. Sanders, Basic Principles of Nanotechnology, 2018
CNTs offer considerable improvements to the field of semiconductors and electronics. Higher storage density, faster processing speeds, and higher energy efficiencies are all possible with CNT-based electronics. To understand the potential advantages of CNT-based electronics, an understanding of the operation of transistors is necessary. Transistors are the most ubiquitous and versatile piece of electronics ever created (Rogers, Adams and Pennathur 2013). A transistor is a three-terminal semiconductor device used to amplify and switch electronic signals and electrical power (Gupta 2013). Currently, integrated circuits (ICs) in personal computers have over a billion transistors, each one turning on and off a billion times every second (Wilson et al. 2002). These on and off states generate the ones and zeros digital computers need for calculations (Kumar and Dubey 2013). Since the invention of the transistor, the semiconductor industry has affected nearly every aspect of our daily life (Chae and Lee 2014). The first transistor was invented in 1947 by William Shockley, John Bardeen, and Walter Brattain (Figure 4.13); they were awarded the Nobel prize in physics in 1956 for their invention (Rogers, Adams and Pennathur 2013). The first transistor was approximately a centimeter high and made of two gold wires separated by 0.02 inches on a germanium crystal (Riordan and Herring 1999; Wilson et al. 2002).
Discovery of fault-introducing tool groups with a numerical association rule mining method in a printed circuit board production line
Published in International Journal of Production Research, 2023
Yeonju Lee, Youngju Kim, Bogyeong Lee, Chang Ouk Kim
Printed circuit boards (PCBs) are thin electronic circuit boards on which copper lines are printed; PCBs connect electronic components such as semiconductor chips and resistors. A PCB production line is a multistage line with various process steps and tools for each process step. The products are processed in units of lots; one lot comprises dozens of panels, which are large sheets containing several PCBs and hundreds of chips. Once all process work is completed, some panels in each lot are sampled, the number of faulty chips in each lot is counted, and the yield of the process, which is the ratio of nondefective products, is calculated. The PCBs are subsequently separated from the panels, yielding the finished PCB products. It is important for PCB manufacturers to reduce the number of faulty chips (i.e. increase the yield of the process) to ensure competitiveness.
Electrochemical double-pulse technique to modulate the roughened surface of copper foil for copper-clad laminates
Published in Transactions of the IMF, 2022
Ni Wang, Qi Chen, Xinyu Gong, Wencheng Hu
With the development of electronic products, higher requirements are being demanded for the intermediate materials, devices, and components of electronic terminal products. As an important component of electronic products, the printed circuit board (PCB) offers a mechanical support to mount electronic components, including resistors, capacitors, inductors, and chips.1 Meanwhile, the fine circuits formed by appropriate etching and metallised holes act as conductive networks to obtain electrical interconnections between the above-mentioned components.2 The core raw material of a PCB is the copper-clad laminate (CCL), which determines the characteristics of a PCB assembly and application fields. The current technology is primarily based on the etching method to prepare single- or double-sided PCBs and an additional laminating process to manufacture multilayer PCBs.
Design reviews on a multipurpose power sockets for different applications
Published in Cogent Engineering, 2018
Chin jie Wong, Umar Nirmal, Sharmeeni Murugan
By introducing the applications of sensor into the socket, it will only be switched on whenever a certain gesture or condition is detected. A sensor is an electronic components that detect any changes or differences in a particular environment and send the related information to other electronic devices, usually a computer processor. The sensor is often used together with other electronic devices to perform an operation whether as simple as a light or as complex as a computer. In today’s lighting technology, the use of sensor in the lighting system is very common as this helps in saving the cost of operating the system, increasing the efficiency of the system and providing automatic control. The types of sensor that will be focusing in this part are motion detector sensor and light sensor.