FGA15N120 IGBT : Pin Configuration & Its Applications

Fairchild Semiconductor has different types of IGBTs under the list of FGAxxN120 series one of the NPT semiconductor is FGA15N120 IGBT, all types of IGBTs from this series uses NPT (Non-Punch Though) technology. This transistor includes less saturation voltage & very little switching loss so that it can be used to design less voltage circuit switching drivers with high efficiency.

In FGA15N120 IGBT, the current rating is denoted after the prefix FGA, current rating is 15A at 125°C and the last number like 120 specifies that the IGBT includes collector-emitter voltage (VCE) is 1200V. This article discusses an overview of FGA15N120 IGBT, pin configuration, features & its applications.

What is FGA15N120 IGBT?

FGA15N120 IGBT (insulated-gate bipolar transistor) is a 3 terminal power semiconductor device like collector, gate & emitter which is used as an electronic switch. This is a high voltage-based IGBT including some features like Collector to Emitter voltage (VCE) is 1200V, the continuous collector current is 30A, very less collector to emitter (CE) saturation voltage is 1.9V & less switching losses.


Similar to all IGBT’s, FGA15N20 also experiences some less switching speed & maximum voltage drop beyond emitter & collector terminals as compared to MOSFETs. So if your application needs maximum efficiency & a quick switching device then you must choose MOSFETs instead of IGBT because IGBTs are mainly used where high voltage switching & current are required.

Pin Configuration:

The pin configuration of FGA15N120 IGBT includes three pins where each pin and its functionality are explained below.

FGA15N120 IGBT Pin Configuration
FGA15N120 IGBT Pin Configuration
  • Pin1 (Gate): This gate terminal is used to control the biasing of the IGBT.
  • Pin2 (Collector): This collector terminal is used to allow the flow of current.
  • Pin3 (Emitter): Current flows out from this terminal.

Features & Specifications:

The features and specifications of FGA15N120 IGBT include the following.

  • The available package is To-3P.
  • The technology used is the advanced NPT Trench.
  • Mount type is through-hole
  • The number of pins is three
  • High Voltage IGBT.
  • Tube packaging
  • Type of input is standard
  • Less saturation voltage typically 1.9V.
  • Voltage from collector to emitter terminal or VCE is 1200V
  • The Collector current of IC is 30A at 25°C temperature.
  • Gate threshold voltage minimum or VGE is 4.5V.
  • Gate threshold voltage maximum or VGE is 8.5V.
  • Voltage from Gate to emitter maximum or VGE is ±20V.
  • Rise time & fall time is 20ns & 100ns correspondingly.
  • The temperature coefficient is Positive.
  • Less switching loss.
  • Extremely improved avalanche capacity.
  • Fairchild’s proprietary trench design.
  • This IGBT provides superior conduction.
  • Avalanche ruggedness is high.
  • Switching performance is high.
  • Parallel operation is simple.

Alternative FGA15N120 IGBTs are TA49123, FGA25N120, FGA180N33, etc. Equivalent FGA15N120 IGBTs are; FGA180N33ATD, FGA15N120ANTDTU_F109, FGA20S120M, FGA25N120ANTD, FGA25N120FTD, FGA30N120FTD, FGA30N60LSD, FGA50N100BNT, FGA25N120ANTDTU_F109 & FGA20N120FTD.


How to use FGA15N120 IGBT/Circuit Diagram:

The combination of a BJT and MOSFET is called an IGBT because like a MOSFET, it has a gate terminal at the input side and collector & emitter on the output side like a BJT. So IGBT uses the benefits of both the transistors.

As compared to MOSFET, IGBT also includes the gate terminal and that has to be activating through the smallest amount of gate voltage to turn OFF the switch. So, the minimum saturation voltage of gate terminal for FGA15N120 IGBT is 4.5V although 5V is used usually in designs,

The circuit diagram of the IGBT is shown below. In this circuit, the Insulated Gate Bipolar Transistor can be switched ‘ON’ & ‘OFF’ by activating the gate terminal. The following circuit uses IGBT to switch the Motor & LED by providing input supply to the Gate terminal of the IGBT.

FGA15N120 IGBT as a Switch Circuit
FGA15N120 IGBT as a Switch Circuit

So, here IGBT in the circuit works as a switch to control these two loads. Once the gate terminal is activated then the IGBT will be activated even after the voltage is detached like a MOSFET due to the capacitance present at the gate terminal on the input. To deactivate the device, the capacitance at the gate terminal has to be released by connecting the gate terminal to the ground using a 10k pull-down resistor, or an IR2104 gate driver IC is used.

If we provide more supply to the Gate terminal, then the emitter terminal of the IGBT remains the transistor in ON condition. Similarly, if we make the Gate terminal negative then IGBT will be in OFF condition. It is similar in MOSFET & BJT switching.

Advantages & Disadvantages:

The advantages of FGA15N120 IGBT include the following.

  • Simple circuit design
  • High voltage capacity
  • Switching speed is fast
  • Switching loss is less
  • On stage power dissipation is low
  • Gate drive condition is low
  • Switching speed is high
  • Input impedance is high
  • It is very simple to turn ON & OFF
  • Outstanding forward & reverse blocking capacities
  • As compared to BJT, switching frequency is high

The disadvantages of FGA15N120 IGBT include the following.

  • Latching up issue
  • High turn off time
  • Cost is high
  • High reverse voltage cannot be blocked
  • Expensive

Where to use FGA15N120 IGBT/Applications:

The applications of FGA15N120 IGBT include the following.

  • The FGA15N120 IGBT has extensive avalanche capacity, so these are resistant to stray inductance problems. So due to this property, the collector to emitter voltage (VCE) exceeds the rated voltage then they do not collapse. Thus, these IGBTs are used in strong switching designs.
  • These are applicable where maximum switching current & voltage is used.
  • Used in high voltage-based applications which includes SMPS, PWM, AC to DC converter, variable speed control, frequency converter applications, etc.
  • This IGBT is used in soft switching & resonant applications like microwave ovens, induction heating, etc.
  • High voltage switching device.
  • High current switching device.
  • Large Solenoids.
  • Tesla Coils.
  • Current source inverter circuits.
  • Matrix converter circuits.
  • Bi-directional based switches
  • Resonant converters
  • Used as auxiliary switches in the major current lane for soft switching.

Please refer to this link to know more about FGA15N120 IGBT Datasheet

Thus, once FGA15N120 IGBT is used in the switching circuit applications, care must be taken that it is not utilized in high frequency-based designs because the voltage drop from collector to emitter of the IGBT enhances once switching frequency is enhanced. Here is a question for you, what are the different IGBT transistors available in the market?

Add Comment