The challenge of this project is to create a model of a capacitive touch screen, including physical modeling of a user`s finger, the touch screen materials, and the touch-detection circuitry. A capacitive touch screen works by measuring the change in capacitance between two conductors caused by a nearby finger. In the touch screen, two transparent
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conductors, which run in perpendicular directions, are separated by the screen. These conductors act as a parallel-plate capacitor where they overlap; the capacitance is determined by numerous physical parameters. For example, the conductor width, length, resistivity, and separation, along with the screen material properties and thickness, all affect the coupling between the conductors. To operate a single pixel of the touch screen, a particular frequency is transmitted along one conductor and received by the other. The capacitive coupling between the conductors causes a particular phase shift in the received signal. When a finger is close enough to where the conductors overlap, it changes the capacitance between the conductors because the finger appears to be grounded. This causes an additional phase shift, which is detected by a simple demodulator circuit and converted into a DC signal. When the DC signal exceeds a given threshold, a touch is detected by the pixel. This process occurs for all of the touch screen pixels to determine which locations are being touched. The traditional approach to modeling a touch screen uses a purely circuit-based design that uses components whose values must be precomputed in another environment. Changes in the design parameters would require the recalculation and re-entry of these and other values into the circuit model before subsequent simulations; this process makes experimentation...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
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The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
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In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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