2n3904: what you should know about this transistor


Between the electronic components analyzed in this blog there are already several types of transistors, both bipolar and field effect. Now is the time to add another one to the list, as is the 2n3904, which is one of the most used in a multitude of electronics projects. In this case it is another BJT, or bipolar, but with some quite interesting characteristics that you should know.

Here you will know what it is exactly, its pinout, where to find device datasheets, how to buy one of them, and a long etc.

What is the 2n3904 transistor?

BJT transistor pinout

El 2N3904 transistor It is a type of bipolar transistor, BJT type for small signal (low intensity and low power, with medium voltages). This type of transistor is an NPN, and it has some interesting characteristics, such as fast switching (it can work with high frequencies), low saturation voltage, and it is suitable for communication and amplification.

You can see inside very everyday gadgets such as televisions, radios, video or audio players, quartz clocks, fluorescent lamps, telephones, etc.

This transistor device is very common. It was patented by Motorola Semiconductor in the 60s, along with PNP 2N3906 (its companion). Thanks to him, efficiency was increased. Plus, it's cheap, with a TO-92 package today, as a replacement for your old metal package.

In addition to Motorola, it has been manufactured by many other companies such as Fairchild, ON Semiconductor, Semtech, Transys Electronics, KEC, Vishay, Rohm Semiconductor, Texas Instruments (TI), Central Semiconductor Corp, etc.

As for the your pinout, you can see it in the previous image, that as is usual in transistors, you have three numbered pins leaving the rounded part of the package towards the back, that is, to interpret the drawing and match the one you hold in your hand now, you should put the flat part in front of you.

Features and datasheet

If you wonder about the detailed features of this type of transistor, here are some of them:

  • Device: Semiconductor transistor
  • Type: bipolar or BJT
  • Package: TO-92
  • Polarity: NPN
  • Voltage: 40v
  • Frequency transition: 300Mhz
  • Power dissipation: 625mW
  • Collector current for direct current: 200mA
  • Direct Current Gain (hFE): 100
  • Joint operating temperature range: -55ºC to 150ºC
  • Emitter collector - saturation voltage less than 300 mV at Ic = 10mA
  • Pins: 3
  • Alternative: NTE123AP

More information on transistors - hwlibre.com

Download datasheet

Where to buy a 2N3904

For, buy a transistor Of these characteristics, you can use the different services of stores specialized in electronics, or on platforms such as Amazon. For example, here are some recommendations:

  • Bojack briefcase with 250 pieces. Transistors of multiple types, among which is the 2n3904.
  • No products found. It also has this pack of 50 units of the 2n3904.
  • TooGoo It also offers another pack somewhat cheaper and with 25 units of the 2n3904.

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