Phase Comparison Carrier Protection: The phase comparison pilot-relaying operates on the principle of comparing the phase position of the currents at the two ends of the protected section. The Phase…
Thyristors Articles: Silicon Controlled Rectifier Principle Operation: Silicon Controlled Rectifier Principle Operation (SCR) consists of four layers of semiconductor material, alternately p-type and n-type as illustrated in Fig. 19-1(a). Because…
Audio Power Amplifiers Articles: Transformer Coupled Class A Amplifier: Class A Circuit – Instead of capacitor coupling, a Transformer Coupled Class A Amplifier may be used to ac couple amplifier…
Optocoupler Circuit Operation: An Optocoupler Circuit Operation (optoelectronic coupler) is essentially a photo-transistor and an LED combined in one package. Figure 20-35(a) and (b) shows the typical circuit and terminal…
Photodarlington Working: The Photodarlington Working shown in (Fig. 20-33) consists of a phototransistor connected in Darlington arrangement with another transistor. This device is capable of producing much higher output currents…
Photoconductive Cell Construction and Working: Photoconductive Cell Construction and Working - Light striking the surface of a material can provide sufficient energy to cause electrons within the material to break…
UJT Circuit Diagram: UJT Circuit Diagram Operation : The Unijunction transistor (UJT) consists of a bar of lightly-doped n-type silicon with a block of p-type material on one side, [see…
Silicon Bilateral Switch: It might be convenient to think of a Silicon Bilateral Switch (SBS) as an SUS with a gate terminal, or as a low-current TRIAC. However, the SBS is…