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:

Shockley or 4-layer diode (PNPN diode)
Figure 1.0 Shockley or 4-layer diode (PNPN diode)

Transistor equivalent of Shockley diode
Figure 1.1 Transistor equivalent
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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.

Diac structure
Figure 1.0 Diac Structure
Diac Symbol
Figure 1.1 Diac Symbol

Operation

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Basic Features of Power Semiconductor Controlled Drives

Power electronics deals with the applications of solid state electronics for the control and conversion of electric power. The conversion systems require switching power semiconductor devices on and off.

The key components of an electric drive controlled by a power … Read more

Surge Suppression in Power Systems

Causes of Power Surges

Transient overvoltages in power systems may arise from a number of sources. Power disturbances resulting from lightning strikes or switching operations on transmission and distribution lines.

The switching of power factor correction capacitors for voltage control … Read more

Switchgear

Switchgear can be defined as equipment used for controlling, regulating and switching ON and OFF power circuits. Switchgear units range from the small moulded-case unit circuit breakers in a household panel board to the huge, air break switches on 750 … Read more

Solid-state Relays (SSR) Features and Operation

A solid-state relay (SSR) is a purely solid-state device used for turning ON and OFF AC loads such as motors.

Features of a Solid-state Relay

Let’s consider the figure below:

Figure (a) SSR being used to drive a motor
Figure (a) SSR being used to drive a motor

Physically, … Read more