electronics

Digital Integrated Circuits Digital integrated circuits are all classified as being one of the following: (i) a small-scale integrated circuit (SSI), (ii) a medium-scale integrated circuit (MSI), (iii) a large-scale integrated circuit (LSI) and (iv) a very-large-scale integrated circuit (VLSI). These categories are based on the number of transistors within each 1C. An SSI 1C […]
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Linear and digital integrated circuits Most integrated circuits (ICs) are classified as being either linear or digital devices. A linear circuit is one whose output signal has a linear relationship with the input signal. Linear ICs are also known as analogue ICs because the signals that they handle may vary continuously over a range of […]
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The fabrication of a complete integrated circuit The main differences between integrated and discrete circuits which perform the same function are that the integrated circuit uses transistors and diodes as liberally as possible. This is because resistors and capacitors occupy more space in the chip than do transistors and they In the fabrication of a […]
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Integrated Circuit Capacitor Integrated capacitors can be fabricated in two ways: either the capacitance of a reverse-biased p-n junction can be utilized, or the capacitance can be provided by a layer of silicon dioxide separating two conducting areas. The construction of a junction-type capacitor is shown in Fig. 14(a). The p-n junction is formed at […]
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Integrated Circuit Resistor Integrated resistors are made using a thin layer of p-type silicon that is diffused at the same time as the base of the transistor. The resistance of a silicon layer depends on the length /, area a and resistivity p of the layer according to                        (5.1) The area a of the […]
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Integrated Circuits The methods used to fabricate silicon planar bipolar and field-effect transistors can be extended to allow a complete circuit to be manufactured in a single silicon chip. All the components, active and passive, which are required by the circuit are formed at the same time in a small piece of silicon, known as […]
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When a transistor is used as a switch it is either biased to be non­conducting or OFF, or it is biased to conduct the maximum possible collector current or be ON. If the base current of a transistor with a collector resistor rl is gradually increased from zero the collector current will increase as well, […]
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Frequency Characteristics The current gain of a transistor is not the same value at all frequencies, but, instead, falls off at the higher frequencies (see Fig. 17). The frequency at which the magnitude of the current gain hfe has fallen to 1/√2 times its low-frequency value hfeo is known as the cut-off frequency fβ of […]
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A number of current-voltage plots are available for the analysis and design of a transistor circuit. The static characteristic curves give information on the value of current flowing into or out of one terminal, for either a given current flowing into or out of another terminal, or a given voltage applied between two terminals. Four […]
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The basic arrangement of the common-base connection (or configuration) is shown in Fig. 4. The transistor has an alternating source of e.m.f. Vs volts r.m.s. and internal resistance Rs ohms connected to its input terminals. The alternating source is connected in series with the emitter-base voltage VEB and it varies the forward bias applied to […]
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