BC817-25

The BC817-25 is a versatile NPN bipolar junction transistor (BJT) commonly used in various electronic applications. It is part of the BC817 series, which is known for its reliability and efficiency in switching and amplification tasks. Here’s a detailed description of its key features and specifications:

Physical Characteristics:

• Package Type: The BC817-25 typically comes in a TO-92 package, which is a cylindrical plastic housing with three leads extending from the base. This package is compact and suitable for through-hole mounting on printed circuit boards (PCBs).
• Dimensions: The TO-92 package generally measures about 4.5 mm in diameter and 10 mm in height, making it small enough for space-constrained applications.

Electrical Specifications:

• Maximum Collector-Emitter Voltage (Vce): The BC817-25 can handle a maximum voltage of 45V between the collector and emitter, making it suitable for a wide range of applications.
• Maximum Collector Current (Ic): It has a maximum collector current rating of 500 mA, allowing it to drive moderate loads effectively.
• DC Current Gain (hFE): The transistor has a current gain (hFE) ranging from 100 to 800, depending on the specific operating conditions. This high gain makes it effective for amplification purposes.
• Transition Frequency (fT): The BC817-25 has a transition frequency of approximately 100 MHz, which indicates its capability for high-speed switching applications.

Thermal Characteristics:

• Junction Temperature (Tj): The maximum junction temperature is typically rated at 150°C, allowing it to operate in various thermal environments.
• Thermal Resistance: The thermal resistance from junction to ambient is relatively low, which helps in managing heat dissipation during operation.

Applications:

The BC817-25 is widely used in:

• Switching Circuits: It can be employed in low to medium power switching applications, such as driving relays, LEDs, and small motors.
• Amplification: It is suitable for audio and RF amplification due to its high gain and frequency response.
• Signal Processing: The transistor can be used in signal processing circuits, including oscillators and amplifiers.

Pin Configuration:

The BC817-25 has a standard pin configuration:

1. Emitter (E): The lead connected to the emitter.
2. Base (B): The lead connected to the base, which controls the transistor's operation.
3. Collector (C): The lead connected to the collector, where the output is taken.

Conclusion:

The BC817-25 from Multicomp is a reliable and efficient NPN transistor suitable for a variety of electronic applications. Its robust specifications, compact size, and versatility make it a popular choice among engineers and hobbyists alike for both switching and amplification tasks.