Leading Power Semiconductor Manufacturer





Bridge Rectifier

Stud Fast Switching Thyristors 100A - 320A

Fast Switching Thyristors (TFI), also known as Fast Impulse Thyristors (TFI), are advanced semiconductor devices designed for rapid switching applications. These thyristors excel in high di/dt resistance, minimal switching losses, and brief turn-on and turn-off times. They efficiently regulate and convert DC and AC currents up to 320A, operating at frequencies up to 10kHz, and are suitable for circuits with voltages up to 1800V, depending on the series.

Key Features and Specifications

  • Current Ratings: Available in a range of current ratings: 100A, 120A, 125A, 150A, 160A, 200A, 250A, 300A, and 320A.
  • High-Power Stud Design: Designed for high-power applications with reduced tq, trr, and Qrr values, and high diT/dt capability (up to 2500 A/µs).
  • Voltage Range: Handles voltages from 600V to 1800V.
  • Applications: Ideal for welding, induction heating and melting, electric transportation, AC drives, UPS systems, and other applications requiring swift turn-on and turn-off times.
  • Construction: Features a ceramic sealed housing that isolates the functional part and semiconductor element from mechanical impacts and environmental factors.
  • Cooling: Utilizes air and water heat sinks, with a focus on ensuring reliable thermal and electrical contact through specified tightening torque and the use of heat-conducting paste.

Technical and Installation Details

  • Part Numbering and Technical Passport: Detailed guides for part numbering, technical specifications, polarity, dimensions, and recommended coolers are available.
  • Assembly Recommendations: Emphasizes the importance of observing the tightening torque (Md) and using heat-conducting paste for optimal heat dissipation during assembly.
  • Polarity: Clearly marked on the case for easy identification.

Performance and Reliability

  • Switching Characteristics: Fast thyristors have very low turn-off times, setting them apart from standard models.
  • Losses: Low static and dynamic losses with high VDRM/VRRM values.
  • Thermal and Electric Cycling: High resistance to both thermal and electric cycling.
  • Cooling Options: Supports both natural and forced air cooling.
  • Quality Assurance: LJ-MD provides a quality guarantee, including a declaration and certificate of conformity if required.

Purchasing Information

  • Price Factors: The final price is influenced by the voltage class, quantity, delivery terms, manufacturer, country of origin, and payment terms.


Fast Switching Thyristors from LJ-MD offer reliable performance for a variety of industrial applications, backed by com


LJTFI 271200149 6 3

  • LJ-MD
  • TFI Fast Switching Thyristor
  • 271 series
  • 200 A, IT(AV)
  • 14 *100V = VRRM
  • 9 Digital code of (dVD//dt)crit
  • 6 Digital code of tq
  • 3 Digital code of tgt
100 A
TypeIT(AV) (Tcase)VDRM
ITSMI2tdv/dtdi/dttqTvj maxRth(j-c)Md ±10%W
LJ-TFI361-100100 (93)600-12002.5312100080012.5-501250.15025240
125 A
TypeIT(AV) (Tcase)VDRM
ITSMI2tdv/dtdi/dttqTvj maxRth(j-c)Md ±10%W
LJ-TFI261-125125 (88)800-14004.580200-2500100016-321250.15025240
LJ-TFI361-125129 (80)600-12002.5100100080020-251250.16025240
160 A
TypeIT(AV) (Tcase)VDRM
ITSMI2tdv/dtdi/dttqTvj maxRth(j-c)Md ±10%W
LJ-TFI261-160160 (83)800-14005.5140200-2500100020-401250.15025240
LJ-TFI271-160160 (98)1000-14006.0170200-2500160016-321250.08530440
LJ-TFI371-160160 (98)600-12004.0801000100010-321250.08430440
200 A
TypeIT(AV) (Tcase)VDRM
ITSMI2tdv/dtdi/dttqTvj maxRth(j-c)Md ±10%W
LJ-TFI271-200200 (95)1000-14006.5200200-2500160020-401250.08530440
LJ-TFI371-200200 (90)600-18009.01801000100025-501250.08430440
250 A
TypeIT(AV) (Tcase)VDRM
ITSMI2tdv/dtdi/dttqTvj maxRth(j-c)Md ±10%W
LJ-TFI271-250250 (88)1000-14007.0230200-2500160025-501250.08530440
LJ-TFI371-250250 (93)1000-14007.0240200-2500160025-501250.08530470
320 A
TypeIT(AV) (Tcase)VDRM
ITSMI2tdv/dtdi/dttqTvj maxRth(j-c)Md ±10%W
LJ-TFI271-320320 (77)1000-14007.5260200-2500160032-631250.08030440
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and discover how our high-performance solutions can drive your innovation.

Our company specializes in manufacturing and selling a diverse range of power semiconductors, including power thyristors, modules, rectifier diodes, avalanche diodes, rotor diodes, welding diodes, triacs, and more. These semiconductors are capable of handling currents up to 15000A and voltages up to 9000V. We also offer air and water heatsinks tailored for these semiconductor devices.

Whether you need a single unit or large volumes, we accommodate orders of any size. Bulk orders benefit from reduced pricing. With a strong track record of customer trust, we supply our products to clients worldwide.

Looking to revolutionize your power control solutions? Look no further. At LJ-MD, we specialize in delivering cutting-edge diode and thyristor technologies that meet the highest industry standards. With a strong focus on innovation, reliability, and performance, our products are designed to excel in a wide range of power applications.

From high surge current capability to precise power control, our diodes and thyristors offer exceptional features that cater to your specific needs. Whether you require efficient rectification, fast switching, or precise phase control, our products deliver reliable and precise results.

At LJ-MD, we understand that every project is unique. That’s why we provide personalized support and guidance to ensure you find the perfect solution for your requirements. Our team of experts is always ready to assist you in selecting the right product and providing technical assistance.

Don’t miss out on the opportunity to optimize your power control systems. CONTACT US now or mail to chen@lj-md.com to discuss your project requirements, and let us help you find the ideal diode or thyristor solution to drive your success.

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