Kits Tins Extra parts
(0 Items in Cart)

Back to products listing page

NPN Transistor (pack of 5) £1.00

Generic placeholder image

NPN Transistor 2N3904

The 2N3904 is a common NPN bipolar junction transistor used for general purpose low-power amplifying or switching applications. The type was registered by Motorola Semiconductor in the mid-sixties, together with the complementary PNP type 2N3906, and represented a significant performance/cost improvement, with the plastic TO-92 case replacing metal cans.

It is designed for low current and power, medium voltage, and can operate at moderately high speeds. This transistor is low cost, widely available and sufficiently robust to be of use by experimenters.


Tech Tin Files: John Bardeen Inventor of the Transistor

  • John Bardeen (May 23, 1908 - January 30, 1991) was an American physicist and electrical engineer, the only person to have won the Nobel Prize in Physics twice: first in 1956 with William Shockley and Walter Brattain for the invention of the transistor; and again in 1972 with Leon N Cooper and John Robert Schrieffer for a fundamental theory of conventional superconductivity known as the BCS theory.
  • On December 23, 1947, Bardeen and Brattain (working without Shockley) succeeded in creating a point-contact transistor that achieved amplification. By the next month, Bell Labs' patent attorneys started to work on the patent applications. Shockley took the lion's share of the credit in public for the invention of transistor, which led to a deterioration of Bardeen's relationship with Shockley.
  • Shockley eventually infuriated and alienated Bardeen and Brattain, and he essentially blocked the two from working on the junction transistor. Bardeen began pursuing a theory for superconductivity and left Bell Labs in 1951. Brattain refused to work with Shockley further and was assigned to another group. Neither Bardeen nor Brattain had much to do with the development of the transistor beyond the first year after its invention
  • The "transistor" (a combination of "transconductance" and "resistor") was 1/50 as large as the vacuum tubes it replaced in televisions and radios and allowed electrical devices to become more compact. This invention of the transistor ushered in our modern electronics revolution, which is without question, the biggest technology changing event in the whole of human history.