BC547 Datasheet – NPN Transistor

BC547 is a Bipolar Junction Transistor (NPN) type, used in a variety of applications such as small signal amplification, switching, and current control.

This transistor consists of three pins. It consists of base, collector, and emitter pins, and each pin operates through appropriate circuit connections.

Part number : BC547

Functions : 45V, 100mA, NPN Epitaxial Silicon Transistor

Package information : TO 92 Pin Type

Manufacturer : ON Semiconductor, Fairchild




NPN Silicon Epitaxial Planar Transistor for switching and AF amplifier application.

BC547 has an NPN structure and uses positive voltage to control current. Applying a positive voltage between the base and emitter allows regulating the current flow between the base and collector. This allows you to amplify small signals or perform switching tasks.

These transistors are subdivided into three groups A, B and C according to their current gain.

In an NPN transistor, the current flows from the emitter to the collector. To turn on the transistor, a small current is applied to the base, which allows a larger current to flow from the collector to the emitter. The base region of an NPN transistor is doped with a material that has fewer electrons than the emitter or collector regions.

The BC547 has characteristics suitable for low-voltage and low-current circuits, typically handling small currents of 100 mA or less. It is used in audio amplification circuits, signal conversion circuits, switching circuits, etc.


1. Switching and Amplifie

2. Low current (max. 100 mA)

3. Low voltage (max. 65 V)

4. Low-Noise: BC549, BC550

5. Complement to BC556, BC557, BC558, BC559, and BC560

Absolute Maximum Ratings


Maximum ratings are those values beyond which device damage can occur.
Maximum ratings applied to the device are individual stress limit values (not
normal operating conditions) and are not valid simultaneously. If these limits
are exceeded, device functional operation is not implied, damage may occur
and reliability may be affected.





1. General purpose switching and amplification.

BC547 Datasheet PDF


Other data sheets within the file : BC546, BC548

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