2N5551

The 2N5551 is a widely used NPN bipolar junction transistor (BJT) manufactured by Central Semiconductor Corp, among other manufacturers. It is designed for general-purpose amplification and switching applications. Here’s a detailed description of its characteristics and specifications:

Physical Characteristics:

• Package Type: The 2N5551 typically comes in a TO-220 package, which is a metal can with three leads extending from the bottom. This package design allows for efficient heat dissipation, making it suitable for applications that require higher power handling.
• Lead Configuration: The transistor has three leads: the collector (C), base (B), and emitter (E). The standard pinout for the TO-220 package is:
  • Pin 1: Base
  • Pin 2: Collector
  • Pin 3: Emitter

Electrical Characteristics:

• Maximum Collector-Emitter Voltage (Vce): The 2N5551 can handle a maximum Vce of 160V, making it suitable for high-voltage applications.
• Maximum Collector Current (Ic): It has a maximum collector current rating of 15A, allowing it to drive significant loads.
• DC Current Gain (hFE): The transistor exhibits a DC current gain (hFE) ranging from 20 to 150, depending on the collector current, which indicates its efficiency in amplifying input signals.
• Transition Frequency (fT): The transition frequency is typically around 100 MHz, which defines the frequency range over which the transistor can operate effectively.

Thermal Characteristics:

• Junction Temperature (Tj): The maximum junction temperature is rated at 150°C, allowing for operation in high-temperature environments.
• Thermal Resistance: The thermal resistance from junction to case is low, which helps in maintaining performance under load.

Applications:

The 2N5551 is suitable for a variety of applications, including:

• Amplification: It can be used in audio amplifiers, RF amplifiers, and other signal amplification circuits.
• Switching: The transistor is effective in switching applications, such as driving relays, motors, and other inductive loads.
• Linear Regulators: It can be used in linear voltage regulator circuits due to its ability to handle significant current and voltage levels.

Key Features:

• High voltage and current ratings make it versatile for various applications.
• Good thermal performance due to its TO-220 package.
• Suitable for both analog and digital applications.

Conclusion:

The 2N5551 from Central Semiconductor Corp is a robust and reliable NPN transistor that is widely used in electronic circuits for amplification and switching. Its combination of high voltage, high current capabilities, and good thermal performance makes it a popular choice among engineers and hobbyists alike.