Specialized
Electronic
Devices
Electronics
Devices
Course Duration
60 minutes
This course covers several categories of semiconductor devices that have
unique characteristics. The specific devices covered include zener diodes, tunnel
diodes, light-emitting diodes, light-sensing diodes, unijunction transistors,
silicon-controlled rectifiers, and field effect transistors. To understand the
operation of these devices and to be able to troubleshoot circuits that contain
them, technicians must be familiar with their special characteristics as well as
with basic semiconductor principles.
Learning Objectives
Upon completion of this module, the student will be able to:
• For a given direction of change in bias voltage, determine the direction of change in depletion region resistance. Use a voltage-current graph to determine current flow for a given magnitude and polarity of bias voltage.
• Using a voltage-current graph, explain the relationship between current and voltage of a zener diode when it is forward biased and when it is reverse biased.
• Explain how a zener diode can regulate the voltage to a load.
• Using a voltage-current graph, explain the relationship between voltage and currenTof a tunnel diode when it is forward biased and when it is reverse biased.
• Explain what happens when a tunnel diode has negative resistance.
• Explain how light-emitting diodes and light-sensing diodes differ from conventional diodes.
• Demonstrate two typical uses of a light-emitting diode and explain the operation of each.
• Differentiate between photovoltaic and photoconductive light-sensing diodes. Describe the construction of a unijunction transistor (UJT).
• Explain how and why a UJT fires.
• Describe the operation of a UJT in a typical oscillator circuit.
• Describe the construction of a silicon-controlled rectifier (SCR) and show the effect of applying a negative potential to the cathode and a positive potential to the anode.
• Define the following terms: forward breakover voltage, holding current, gate, and gate potential.
• Describe or demonstrate the effect of applying different potentials to an SCR gate.
• Demonstrate two ways of reducing current flow through an SCR. Given an AC circuit containing an SCR and a UJT, show how the DC output from the SCR can be controlled.
Get in touch:
Aberdeen Energy Park,
Claymore Drive,
Aberdeen AB23 8GD
T: +44 (0) 1224 708430
info@atlasknowledge.com
www.atlasknowledge.com
Learning. Technology. Solutions.
To request a demonstration or to purchase this course please contact your
Atlas Account Manager or email info@atlasknowledge.com
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