Category: Electronics
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Voltage Doubler Circuit Operation
A voltage multiplier is a specialized rectifier circuit capable of producing dc output voltage which is theoretically an integer times the AC peak input, for instance, it is possible to get 200 VDC from a 100 Vpeak AC source using a voltage doubler, 300 VDC using a voltage tripler or 400 VDC using a voltage…
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Clamper Circuits – Features & Applications
A clamper circuit or dc restorer is used to clamp a peak of a waveform to a specific DC level compared with a capacitive coupled signal which swings about its average DC level (normally 0 V). If the diode is removed from the clamper, it defaults to a simple coupling capacitor – that is, no…
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Clipper Circuits – Features & Applications
A clipper also referred to as a limiter is a circuit which removes the peak of a waveform. A clipper consists of diodes, resistors and sometimes DC sources to clip or limit the output to a certain level. The input-output characteristics of clipper circuits are typically similar to those of the forward-biased and reverse-biased diode…
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Linear/Analog vs. Digital Integrated Circuits (ICs)
Linear ICs (LICs) also referred to as analog ICs are characterized by inputs and outputs that can take a continuous range of values. In addition, the outputs are generally proportional to the inputs. On the other hand, Digital ICs contain circuits whose input and output voltages are limited to two possible levels i.e. low or…
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PIN Diode – Features & Applications
PIN diode is characterized by fast low capacitance switching. A PIN diode is fabricated in a similar fashion to a silicon switching diode with an intrinsic region added between the PN junction layers. This generates a thicker depletion region, the insulating layer at the junction of a reverse biased diode. This results in lower capacitance…
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Schottky Diode – Features & Applications
Schottky diode is fabricated as a metal-to-N junction rather than a P-N semiconductor junction. Also referred to as hot-carrier diodes, Schottky diodes are characterized by fast switching times (low reverse-recovery time), low forward voltage drop (normally 0.25 to 0.4 volts for a metal-silicon junction), and low junction capacitance. The forward voltage drop (VF), reverse-recovery time…
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The Principle and Application of IMPATT Diode
The Impact Avalanche Transit Time (IMPATT) diode is a high power radio frequency (RF) generator that operates from 3 to 100 GHz. IMPATT diodes are manufactured from silicon, gallium arsenide or silicon carbide. An IMPATT diode is reverse biased above the breakdown voltage. The high doping levels produce a thin depletion region. The arising high…
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The Shockley Diode Features & Operation
The Shockey diode is a four layer sandwich of PNPN semiconductor material very similar to the SCR but without a gate as illustrated in the Figure 1.0 below: The Operation of Shockley Diode A Shockley diode can be turned ON by applying enough voltage between anode and cathode. This voltage will cause one of the…
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The Diac Features & Applications
Features of a Diac The diac is a two-terminal, semiconductor, bi-directional switching device. It can conduct in both directions. The diac closely resembles a PNP transistor without an external base terminal. Operation of a Diac The diac does not conduct except for a small leakage current) until the breakover voltage VS is reached, typically 20…
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Unijunction Transistor Features and Operation
The unijunction transistor (UJT) is a three terminal, single-junction device which exhibits negative resistance and switching characteristics totally unlike those of conventional bipolar transistors. The UJT consists of a bar of n-type having ohmic contacts designated Base 1 (B1) and Base 2 (B2) on either side of a single PN junction designated the emitter. An…