2N3904

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title: "2N3904" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["jedec-standards", "commercial-transistors", "bipolar-transistors"] description: "Common NPN bipolar junction transistor" topic_path: "general/jedec-standards" source: "https://en.wikipedia.org/wiki/2N3904" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Common NPN bipolar junction transistor ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/4/4c/2N3904.jpg" caption="A 2N3904 made by [[Motorola]]. The pinout from left to right is: Emitter, Base, Collector."] ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/5/57/Joule_thief.jpg" caption="A 2N3904 (lower left) in a [[TO-92]] package on a breadboard"] ::

The 2N3904 is a common NPN bipolar junction transistor used for general-purpose low-power amplifying or switching applications. It is designed for low current and power, medium voltage, and can operate at moderately high speeds. It is complementary to the 2N3906 PNP transistor. Both types were registered by Motorola Semiconductor in the mid-1960s.

Device packaging and specifications

The construction of the 2N3904 and 2N3906 in the 1960s represented a significant performance and cost improvement, with the plastic TO-92 case replacing metal cans. This transistor is a low-cost device, widely available and sufficiently robust to be of use by experimenters and electronics hobbyists.

It is a 200 mA, 40 V, 625 mW transistor with a transition frequency of 300 MHz, with a minimum beta, or current gain, of 100 at a collector current of 10 mA.

Related parts

Electrically similar devices, such as the MMBT3904, are available in a variety of small through-hole and surface-mount packages, including TO-92, SOT-23, and SOT-223, with package-dependent thermal ratings from 625 milliwatts to 1 watt.

The complementary PNP transistor is 2N3906.

Part numbers

::figure[src="https://upload.wikimedia.org/wikipedia/commons/e/ea/2n3904.jpg" caption="Pinout of 2N3904 in TO-92 package. Top view or PCB layout view is shown in the lower right corner."] ::

The 2N3904 (NPN) and 2N3906 (PNP) are complementary transistor pairs. These transistors are available in package styles TO-92, SOT23, SOT223 with different prefixes.

::data[format=table title="Transistor part numbers"]

BJT	Thru-hole	Surface-mount	TO92	SOT23	SOT223
NPN	2N3904	MMBT3904	PZT3904
PNP	2N3906	MMBT3906	PZT3906
::

References

References

1. JEDEC]]
2. (August 2012). "2N3904 Datasheet (TO-92)".
3. (February 2010). "2N3906 Datasheet (TO-92)".
4. (January 2013). "2N3904 Datasheet (TO-92)".
5. (October 2017). "2N3904 Datasheet (TO-92)".
6. Silver, H. Ward. (2008). "Circuitbuilding do-it-yourself for Dummies". For Dummies.
7. Predko, Michael. (2004). "123 robotics experiments for the evil genius". McGraw-Hill Professional.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::