What Is the Main Function of IGBT Compared to Other Transistors?

Understanding the IGBT’s Role

What is the main function of IGBT in modern electronics? Simply put, it acts as a high-power switch that combines the best features of MOSFETs and BJTs.

What are IGBTs exactly? They are Insulated Gate Bipolar Transistors—devices designed for efficient high-voltage switching. Unlike standard transistors, they excel in applications demanding both power and precision.

This article compares IGBTs to MOSFETs and BJTs, explaining why they dominate in industries like renewable energy, EVs, and industrial automation.

What Is IGBT and How It Works?

An IGBT’s cross-section reveals three layers:

1. Gate – Controls switching (like a MOSFET)

2. Collector & Emitter – Handle high current (like a BJT)

3. N-drift region – Optimizes voltage blocking

IGBT module function:

✔ Efficiently switches high power

✔ Reduces heat loss

✔ Integrates protection features

Where IGBTs Outperform Other Transistors

1. Electric Vehicles (EVs)

• SiC IGBT module variants improve efficiency
• Handles rapid acceleration power demands

2. Solar Inverters

• Converts DC to AC with minimal loss
• More reliable than MOSFETs at high voltages

3. Industrial Motor Drives

• IGBT discrete units control heavy machinery
• Better thermal performance than BJTs

IGBT vs. MOSFET vs. BJT: Key Differences

1. Control Method

• IGBT: Voltage-controlled (like a MOSFET)
• BJT: Current-controlled
• MOSFET: Voltage-controlled but limited at high voltages

2. Power Handling

• IGBT: Best for 600V+ applications
• MOSFET: Ideal for high-frequency, low-voltage
• BJT: Older tech, less efficient

3. Switching Speed

• MOSFET: Fastest (MHz range)
• IGBT: Medium (kHz range)
• BJT: Slowest

IGBT Advantages Over Alternatives

When to Choose IGBTs

1. High-power systems (e.g., wind turbines)

2. Medium-frequency switching (e.g., motor drives)

3.Harsh environments (e.g., industrial settings)

Future of IGBTs

Hybrid SiC IGBT modules – Boosting efficiency further

Smarter gate drivers – Enhancing switching precision

Lower costs – Expanding into more applications

Conclusion

What is the main function of IGBT? It bridges the gap between power and control, outperforming other transistors in critical applications.

Key takeaways:

✔ IGBTs dominate high-voltage, medium-speed switching

✔ They’re more efficient than BJTs for power apps

✔ Future SiC IGBT modules will push boundaries further