Datasheet NPN transistors

Some common NPN transistor types include:

  • 2N3904: A widely used general-purpose NPN transistor.
  • BC547: Popular in various electronic circuits.
  • 2SC1815: Known for its good performance.
  • 2N2222: A very common and versatile transistor.
  • TIP41: Often used in power amplifier circuits.
  • MJE13003: Commonly employed in switching applications.


NPN transistors are fundamental components in the world of electronics, playing crucial roles in a wide range of applications. A detailed datasheet provides essential information about their characteristics, performance, and specifications.

The datasheet typically begins with an overview of the transistor model, highlighting its key features and intended applications. It may include details about the packaging type, which can impact its physical size and mounting options.

One of the primary sections in the datasheet is the electrical specifications. This includes parameters such as the collector-emitter voltage rating (VCEO), which indicates the maximum voltage that can be applied between the collector and emitter without causing damage. The base-emitter voltage (VBE) and collector current (IC) specifications are also important, as they define the transistor's operating limits.

The gain characteristics of the NPN transistor are often specified. This can be expressed as the current gain (hFE), which represents the ratio of collector current to base current under certain conditions. The datasheet may provide a range or typical value for hFE to give an indication of the transistor's amplification capabilities.

Switching characteristics are crucial in applications where the transistor is used for on/off control. Parameters such as the turn-on and turn-off times, as well as the storage time, are detailed to understand the transistor's speed and efficiency in switching operations.

Thermal specifications are also significant. The maximum junction temperature (TJmax) indicates the highest temperature the transistor can tolerate without degradation. Information about the thermal resistance (Rθ) helps in determining how effectively heat can be dissipated from the device.

In addition to these core specifications, the datasheet may include other details such as the recommended operating conditions, such as temperature range and supply voltage range. It may also provide information about the transistor's equivalent circuit model, which is useful for circuit analysis and simulation.

Furthermore, some datasheets may include graphs and curves to visually represent key characteristics. For example, a collector current vs. collector-emitter voltage curve can provide a more comprehensive understanding of the transistor's behavior across different voltage and current conditions.

It's important to note that different NPN transistor models will have specific datasheets tailored to their unique properties and intended uses. Engineers and designers rely on these datasheets to select the appropriate transistor for their specific circuits, ensuring optimal performance and reliability. When working with NPN transistors, a careful examination of the datasheet is essential to make informed decisions and design circuits that meet the required specifications and functionality.