BC109 NPN Transistor Technical Summary

Overview

The BC109 is a silicon NPN transistor housed in a hermetically sealed TO-18 metal package, designed for general-purpose amplification and switching applications. It is part of the BC107/BC108/BC109 family, offering reliable performance in a robust package. The transistor is suitable for use in environments requiring stable operation across a wide temperature range, thanks to its hermetically sealed construction.

With its high voltage ratings and low noise characteristics, the BC109 is ideal for audio amplification, signal processing, and other low-power applications. The device is available with various screening options to meet stringent quality and reliability requirements.

Features

• Silicon NPN Construction: Provides reliable performance with low leakage currents.
• Hermetically Sealed TO-18 Package: Ensures durability and protection against environmental factors.
• High Voltage Ratings: VCBO (Collector-Base Voltage) of 50V, VCEO (Collector-Emitter Voltage) of 30V, and VEBO (Emitter-Base Voltage) of 6V.
• Low Noise: Suitable for audio and sensitive signal amplification.
• Wide Operating Temperature Range: -65°C to +175°C ambient operating and storage temperature range.
• Screening Options Available: Enhanced testing and quality assurance for critical applications.

Applications

The BC109 is versatile and finds use in a variety of electronic circuits, including:

• Audio Amplification: Low-noise characteristics make it ideal for preamplifiers and audio signal processing.
• Signal Switching: Can be used in switching circuits due to its fast response times.
• General-Purpose Amplification: Suitable for small-signal amplification in analog circuits.
• Industrial Control Systems: Robust construction allows for use in harsh environments.
• Test and Measurement Equipment: Reliable performance in precision instruments.

Electrical Characteristics

The following table summarizes the key electrical characteristics of the BC109 transistor at TA = 25°C unless otherwise specified:

Absolute Maximum Ratings

• Collector-Base Voltage (VCBO): 50V
• Collector-Emitter Voltage (VCEO): 30V
• Emitter-Base Voltage (VEBO): 6V
• Continuous Collector Current (IC): 100mA
• Peak Collector Current (ICM): 200mA
• Power Dissipation (Ptot): 300mW at Tamb = 25°C
• Ambient Operating Temperature Range (Tamb): -65°C to +175°C
• Storage Temperature Range (Tstg): -65°C to +175°C

Typical Performance Characteristics

The BC109 exhibits the following typical performance characteristics under standard operating conditions:

• DC Current Gain (hFE): Typically 110 to 450 at IC = 2mA, VCE = 5V.
• Transition Frequency (fT): Typically 150MHz at IC = 10mA, VCE = 5V.
• Noise Figure (NF): Typically 4dB at f = 1kHz, IC = 100µA, VCE = 5V.
• Collector-Emitter Saturation Voltage (VCE(sat)): Typically 0.6V at IC = 100mA, IB = 10mA.

Package Information

The BC109 is housed in a TO-18 metal can package, which provides excellent thermal and mechanical stability. The package dimensions and pin configuration are as follows:

Mechanical Data

• Package Type: TO-18 (Metal Can)
• Dimensions: 5.33mm (0.210 inches) diameter, 4.19mm (0.165 inches) height.
• Lead Spacing: 2.54mm (0.100 inches) nominal between pins.
• Lead Diameter: 0.48mm (0.019 inches) nominal.

Pin Configuration

Viewed from the underside of the package (lead side), the pinout is as follows:

• Pin 1: Emitter
• Pin 2: Base
• Pin 3: Collector

Conclusion

The BC109 is a high-performance NPN transistor designed for general-purpose amplification and switching applications. Its hermetically sealed TO-18 package ensures reliability in demanding environments, while its electrical characteristics make it suitable for a wide range of low-power circuits. With screening options available, the BC109 meets the needs of both commercial and industrial applications where quality and performance are critical.