An insulated-gate bipolar transistor (IGBT) is a three-terminal semiconductor device that combines high efficiency and fast switching. It consists of alternating P-N-P-N layers controlled by a metal-oxide-semiconductor (MOS) gate structure, without regenerative action. The IGBT structure is similar to a thyristor with an isolated MOS gate that completely suppresses the thyristor action. IGBTs are used in switching power supplies for applications requiring high power, such as variable frequency drives, electric vehicles, and air conditioners. The IGBT combines the simple gate drive of MOSFETs with the high-current and low-saturation-voltage capabilities of bipolar transistors.

1. BasicsofBiomedicalEngineering
INSULATED-GATE
BIPOLAR TRANSISTOR
(IGBT)
PREPARED BY ATHEENA PANDIAN

2. Today's
Agenda
P R E S ENTATION OUTLI N E
What is insulated-gate bipolar
transistor (IGBT)?
Symbol
Uses
Characteristics
Advantages
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3. An insulated-gate bipolar transistor
(IGBT) is a three-terminal power
semiconductor device primarily
used as an electronic switch which,
as it was developed, came to
combine high efficiency and fast
switching.
IG B T

4. Symbol

5. Construction
It consists of four
alternating layers (P-N-P-
N) that are controlled by
a metal–oxide–
semiconductor (MOS) gate
structure without
regenerative action.

6. S T R U CTURE
The structure of the IGBT is topologically
the same as a thyristor with a 'MOS' gate
(MOS gate thyristor), the thyristor action is
completely suppressed and only
the transistor action is permitted in the
entire device operation range.

7. D E V I CE STRUCTURE
An IGBT cell is constructed similarly to a n-
channel vertical-construction power
MOSFET, except the n+ drain is replaced
with a p+ collector layer, thus forming a
vertical PNP bipolar junction transistor.
This additional p+ region creates a cascade
connection of a PNP bipolar junction
transistor with the surface n-
channel MOSFET.

8. It is used in switching power
supplies in high power
applications: variable-frequency
drives (VFDs), electric cars, trains,
variable speed refrigerators, lamp
ballasts, and air-conditioners.
uses

9. Static characteristic of an IGBT

10. Advantages
The IGBT combines the simple gate-drive characteristics
of power MOSFETs with the high-current and low-
saturation-voltage capability of bipolar transistors
The IGBT combines an isolated-gate FET for the control
input and a bipolar power transistor as a switch in a
single device
The IGBT is used in medium- to high-power applications
like switched-mode power supplies, traction motor
control and induction heating.
Large IGBT modules typically consist of many devices in
parallel and can have very high current-handling
capabilities in the order of hundreds of amperes with
blocking voltages of 6500 V.
These IGBTs can control loads of hundreds of kilowatts.
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11. Thank You