Article · Wikipedia archive · Last revised Jun 5, 2026

Static induction transistor

The static induction transistor (SIT) is a type of field-effect transistor (FET) capable of high-speed and high-power operation, with low distortion and low noise. It is a vertical structure device with short multichannel. The device was originally known as a VFET, with V being short for vertical. Being a vertical device, the SIT structure offers advantages in obtaining higher breakdown voltages than a conventional FET. For the SIT, the breakdown voltage is not limited by the surface breakdown between gate and drain, allowing it to operate at a very high current and voltage. The SIT has a current-voltage characteristic similar to a vacuum tube triode and it was therefore used in high-end audio products, including power amplifiers from Sony in the second half of the 1970s and Yamaha from 1973-1980. The Sony n-channel SIT had the model number 2SK82 with its p-channel complement named 2SJ28.

Last revised
Jun 5, 2026
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The static induction transistor (SIT) is a type of field-effect transistor (FET) capable of high-speed and high-power operation, with low distortion and low noise.1 It is a vertical structure device with short multichannel. The device was originally known as a VFET, with V being short for vertical.2 Being a vertical device, the SIT structure offers advantages in obtaining higher breakdown voltages than a conventional FET. For the SIT, the breakdown voltage is not limited by the surface breakdown between gate and drain, allowing it to operate at a very high current and voltage. The SIT has a current-voltage characteristic similar to a vacuum tube triode and it was therefore used in high-end audio products, including power amplifiers from Sony in the second half of the 1970s and Yamaha from 1973-1980. The Sony n-channel SIT had the model number 2SK82 with its p-channel complement named 2SJ28.2

Characteristics

A SIT has:

  • short channel length
  • low gate series resistance
  • low gate-source capacitance
  • small thermal resistance
  • low noise
  • low distortion
  • high audio frequency power capability
  • short turn-on and turn-off time, typically 0.25 μs

History

The SIT was invented by Japanese engineers Jun-ichi Nishizawa and Y. Watanabe in 1950.3

See also

See also

References

References

  1. Nishizawa, Jun-ichi (December 15, 1974). "Field-effect transistor versus analog transistor (static induction transistor)". IEEE Transactions on Electron Devices. 22 (4): 185–197. doi:10.1109/T-ED.1975.18103. S2CID 37015648.
  2. Pass, Nelson (2013). "The Sony VFET Amplifier 40 Year Commemorative" (PDF). First Watt. Retrieved August 17, 2022.
  3. F. Patrick McCluskey; Thomas Podlesak; Richard Grzybowski, eds. (1996). High Temperature Electronics. CRC Press. p. 82. ISBN 0-8493-9623-9.