Power Electronics MCQs Part 3 Which of following doping is done to make a signal diode suitable for high current high voltage applications with minimum losses Which of following doping is done to make a signal diode suitable for high current high voltage applications with minimum losses Correct answer: 1. A lightly doped n layer … Read more
Power Electronics MCQs Part 2 Of following, the device that does not belong to the transistor family is Of following, the device that does not belong to the transistor family is Correct Answer: 2. GTO Explanation: GTO or gate turn off switch (GTO) belongs to Thyristors. Thyristors are a broad classification of bipolar-conducting semiconductor devices having … Read more
The SPICE (simulation program, integrated circuit emphesis) electronic simulation program provides circuit elements and models for semiconductors. The SPICE element names begin with d, q, j, or m correspond to diode, BJT, JFET and MOSFET elements, respectively. These elements are accompanied by corresponding “models” These models have extensive lists of parameters describing the device. Though, we do not list … Read more
Superconducting devices, though not widely used, have some unique characteristics not available in standard semiconductor devices. High sensitivity with respect to amplification of electrical signals, detection of magnetic fields, and detection of light are prized applications. High speed switching is also possible, though not applied to computers at this time. Conventional superconducting devices must be … Read more
Most integrated circuits are digital, based on MOS (CMOS) transistors. Every couple of years since the late 1960’s a geometry shrink has taken place, increasing the circuit density– more circuitry at lower cost in the same space. As of this writing (2006), the MOS transistor gate length is 65-nm for leading edge production, with 45-nm … Read more
The manufacture of only silicon based semiconductors is described in this section; most semiconductors are silicon. Silicon is particularly suitable for integrated circuits because it readily forms an oxide coating, useful in patterning integrated components like transistors. Silicon is the second most common element in the Earth’s crust in the form of silicon dioxide, SiO2, … Read more
Thyristors are a broad classification of bipolar-conducting semiconductor devices having four (or more) alternating N-P-N-P layers. Thyristors include: silicon controlled rectifier (SCR), TRIAC, gate turn off switch (GTO), silicon controlled switch (SCS), AC diode (DIAC), unijunction transistor (UJT), programmable unijunction transistor (PUT). Only the SCR is examined in this section; though the GTO is mentioned. Shockley … Read more
The insulated-gate field-effect transistor (IGFET), also known as the metal oxide field effect transistor (MOSFET), is a derivative of the field effect transistor (FET). Today, most transistors are of the MOSFET type as components of digital integrated circuits. Though discrete BJT’s are more numerous than discrete MOSFET’s. The MOSFET transistor count within an integrated circuit may approach hundreds of … Read more
The field effect transistor was proposed by Julius Lilienfeld in US patents in 1926 and 1933 (1,900,018). Moreover, Shockley, Brattain, and Bardeen were investigating the field effect transistor in 1947. Though, the extreme difficulties sidetracked them into inventing the bipolar transistor instead. Shockley’s field effect transistor theory was published in 1952. However, the materials processing … Read more
The bipolar junction transistor (BJT) was named because its operation involves conduction by two carriers: electrons and holes in the same crystal. The first bipolar transistor was invented at Bell Labs by William Shockley, Walter Brattain, and John Bardeen so late in 1947 that it was not published until 1948. Thus, many texts differ as to the … Read more