THYRISTOR STRUCTURE AND
SPECIFICATION
Eric Canniff
Cody Johnson
INTRODUCTION AND OUTLINE
History
 Basic Characteristics
 Structure
 Specifications
 Applications

HISTORY
William Shockley proposed the concept of the
Silicon Controlled Rectifier (SCR) in 1950
 Engineers at Bell Labs supported this idea
 In 1956 Under the supervision of Gordon Hall,
General Electric created an SCR
 Soon became a commercial product, due to the
efforts of Frank W. Gutzwiller
 Predecessor was a gas filled tube device called a
Thyratron

BASIC CHARACTERISTICS

Thyristor is composed of four alternate layers of
N-type and P-type material
TWO TRANSISTORS EQUIVALENT CIRCUIT
I-V CHARACTERISTICS
STRUCTURE
BILATERAL STRUCTURE
Allows for positive and negative voltages to pass
TRIAC STRUCTURE
MOS TURN-OFF THYRISTOR
MOS GATED THYRISTOR

V Groove Mos gated thyristor
LIGHT TRIGGERED THYRISTOR (LTT)
Have an optically sensitive region in the gate
 Used for protection of control circuit for HVDC
 Usually triggered by Infrared Light

SPECIFICATIONS

50A Medium Power Thyristor
APPLICATIONS
DC transmission of
power from Manitoba
Hydro dams
 Heart of High-voltage
direct current
conversions now a days

SUMMARY AND CONCLUSION
Thyristor is a 4-layered alternating pn-material
device
 Semiconductor Controlled Rectifier (SCR)
 Needs only a small gate pulse to stay on
 4 Basic structures
 Mainly used in high voltage application

REFERENCE SLIDE
Neamen, Donald A. Semiconductor Physics and
Devices. Fourth ed. New York: McGraw-Hill,
2012. 691-701. Print.
 Vishay, . Medium Power Thyristors. N.p., 19
Sept. 2008. Web. 27 Apr. 2013.
<http://www.vishay.com/docs/93711/50ria.pdf>.
 Sentaurus Technology Template: Light-Triggered
Thyristor. N.p., 2013. Web. 28 Apr. 2013.
<http://www.synopsys.com/Tools/TCAD/Pages/thy
ristor.aspx>.

KEY CONCEPTS
Structures
 Switching Characteristics
 Triggering
 Types
 Applications
