on October 10th 286

Understanding the BC107 Transistor

The BC107 transistor is a versatile and widely used electronic component that can be found in many circuits for switching and amplifying signals. Known for its reliability and stability, this NPN transistor is easy to use and works well in various projects, from audio systems to control applications. In this article, you’ll learn everything you need to know about the BC107, including its structure, how it works, and why it’s still a great choice for your electronics projects.

Catalog

BC107 Transistor Overview

The BC107 is a popular NPN bipolar junction transistor used in many circuits for switching and amplification. It comes in a TO-18 metal case and has three main terminals: the emitter, base, and collector. When you apply a small current to the base, it controls a larger current flowing between the emitter and collector, making it easy to manage current flow in electronic circuits.

The emitter is designed to inject electrons into the base, while the base itself is thin and lightly doped, allowing you to control the flow of electrons with precision. Adjusting the base voltage lets you influence the overall behavior of the transistor, making it a good choice for projects that need accurate control of current.

The collector, which operates at a higher voltage than the base, captures the electrons moving through the transistor. This setup helps maintain signal quality, especially in amplification tasks. The BC107’s design, which uses the interaction between the emitter-base and base-collector junctions, supports effective switching and clear signal amplification.

Another feature of the BC107 is its strong thermal stability, which ensures consistent performance even in changing temperatures. This makes it reliable in different environments and helps maintain the overall stability of your circuit.

BC107 Pinout and Functionality

Base

The base of the BC107 transistor plays a key role in controlling its behavior and determining its ON or OFF states. It acts as a gatekeeper, deciding when the transistor will conduct. When you apply the right amount of current to the base, the transistor begins to operate according to its intended function.

In practical use, it’s necessary to set the base current accurately to ensure the transistor performs well within its limits. You may use resistors or biasing networks to adjust the base current and fine-tune how the transistor responds to signals.

Emitter

The emitter of the BC107 transistor is where current exits. It is often connected to ground in typical circuit setups, such as common-emitter configurations. The emitter plays an important part in achieving voltage gain in these circuits.

The way you connect and ground the emitter can significantly impact the stability and performance of the circuit. Therefore, it’s worth paying attention to these details during the design phase.

Collector

The collector of the BC107 is where current enters the transistor. It’s usually connected to the load in the circuit, working together with the base and emitter to either amplify or switch electronic signals.

To keep the transistor functioning reliably, you need to consider the collector’s voltage, current handling, and power dissipation capabilities. Proper thermal management, such as using heat sinks, can help maintain stable performance and prevent overheating in various conditions.

BC107 CAD Representation

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Symbol

Key Features of the BC107 Transistor

Small Signal Transistor Classification

The BC107 is classified as a small signal NPN transistor, which allows it to amplify or switch low-level signals in electronic circuits. This type of transistor is ideal for applications like audio amplification, signal processing, and switching tasks within digital circuits.

High Current Gain

The BC107 offers a maximum current gain (hFE) of 450, enabling it to amplify a small base current into a much larger collector current. This characteristic is beneficial for circuits where maintaining the integrity and strength of signals is important.

Continuous Collector Current Capability

The BC107 can handle a continuous collector current (IC) of up to 100mA, making it a reliable choice for circuits that have moderate current needs. This makes it suitable for hobby projects, prototypes, and for powering components like LEDs or small motors.

Voltage Ratings

The BC107 has clearly defined voltage ratings that set its operational limits: a Collector-Emitter voltage (VCEO) of 45V, a Collector-Base voltage (VCB0) of 50V, and an Emitter-Base voltage (VBE0) of 6V. These ratings provide a solid framework for designing circuits that are stable and can handle different electrical conditions.

Packaging

The BC107 is enclosed in a TO-18 metal can package, offering strong physical protection and enhanced thermal dissipation. This type of packaging is favored in environments where durability and heat management are priorities, such as in industrial electronics or aerospace applications.

Technical Specifications

Type	Parameter
Contact Plating	Tin
Mount	Through Hole
Mounting Type	Through Hole
Package / Case	TO-206AA, TO-18-3 Metal Can
Number of Pins	3
Transistor Element Material	SILICON
Collector-Emitter Breakdown Voltage	45V
Number of Elements	1
hFE Min	200
Operating Temperature	175°C TJ
Packaging	Tube
JESD-609 Code	e3
Part Status	Obsolete
Moisture Sensitivity Level (MSL)	1 (Unlimited)
Number of Terminations	3
Termination	Through Hole
ECCN Code	EAR99
Voltage - Rated DC	45V
Max Power Dissipation	300mW
Terminal Position	BOTTOM
Peak Reflow Temperature (Celsius)	NOT SPECIFIED
Current Rating	100mA
Time @ Peak Reflow Temperature - Max (s)	NOT SPECIFIED
Base Part Number	BC107
Pin Count	3
Qualification Status	Not Qualified
Element Configuration	Single
Power Dissipation	300mW
Transistor Application	AMPLIFIER
Polarity / Channel Type	NPN
Transistor Type	NPN
Collector Emitter Voltage (VCEO)	45V
Max Collector Current	100mA
DC Current Gain (hFE) (Min) @ Ic, Vce	110 @ 2mA 5V
Current - Collector Cutoff (Max)	15nA ICBO
Vce Saturation (Max) @ Ib, Ic	600mV @ 5mA, 100mA
Transition Frequency	150MHz
Collector Base Voltage (VCBO)	50V
Emitter Base Voltage (VEBO)	6V
Height	5.3mm
Length	5.8mm
Width	5.8mm
REACH SVHC	No SVHC
RoHS Status	ROHS3 Compliant

BC107 Alternatives

Part Number	Description	Manufacturer
JANTXV2N5581TRANSISTORS	Small Signal Bipolar Transistor, 0.8A I(C), 50V V(BR)CEO, 1-Element, NPN, Silicon, TO-46, HERMETIC SEALED, METAL CAN-3	Semicoa Semiconductors
2N706TRANSISTORS	Small Signal Bipolar Transistor, 0.05A I(C), 15V V(BR)CEO, 1-Element, NPN, Silicon, TO-18, TO-18, 3 PIN	Microsemi Corporation
2N2369ZTRANSISTORS	15V, NPN, Si, SMALL SIGNAL TRANSISTOR, TO-18	STMicroelectronics
BCW65ALT1TRANSISTORS	Small Signal Bipolar Transistor, 0.8A I(C), 32V V(BR)CEO, 1-Element, NPN, Silicon, TO-236AB	Motorola Semiconductor Products
MPSL51TRETRANSISTORS	Small Signal Bipolar Transistor, 100V V(BR)CEO, 1-Element, PNP, Silicon, TO-92	Central Semiconductor Corp
MPSL51/D27ZTRANSISTORS	600mA, PNP, Si, SMALL SIGNAL TRANSISTOR, TO-92	Texas Instruments
BCW65ATRTRANSISTORS	Small Signal Bipolar Transistor, 32V V(BR)CEO, 1-Element, NPN, Silicon	Central Semiconductor Corp
MPSL51/D75ZTRANSISTORS	600mA, PNP, Si, SMALL SIGNAL TRANSISTOR, TO-92	Texas Instruments
BCW65ATR13LEADFREETRANSISTORS	Small Signal Bipolar Transistor, 32V V(BR)CEO, 1-Element, NPN, Silicon	Central Semiconductor Corp
MPSL51TRELEADFREETRANSISTORS	Small Signal Bipolar Transistor, 100V V(BR)CEO, 1-Element, PNP, Silicon, TO-92	Central Semiconductor Corp

BC107 Usage Context

The BC107 transistor is well-suited for low-signal applications, making it a popular choice in sensitive signal processing systems and television receivers. Its low-noise characteristics help maintain signal clarity, making it ideal for environments where clean signal output is essential. Even with many newer transistors available, the BC107 has remained in use due to its consistent and reliable performance over the years.

In signal processing, the BC107's low noise capability preserves the integrity and quality of signals, making it effective in circuits where minimal distortion is necessary. Its use in TV receivers demonstrates its ability to maintain stable signals and prevent signal loss, ensuring smooth and uninterrupted performance.

The BC107 also performs well in analog circuits, especially those that require precise low-level signal amplification. Its specific characteristics make it a strong contender in analog applications, often surpassing newer alternatives that may not meet the unique demands of analog technology as effectively.

Maximum Ratings for BC107

Symbol	Parameter	Value	Unit
VCBO	Collector-Base Voltage (IE = 0)	50	V
VCEO	Collector-Emitter Voltage (IB = 0)	45	V
VEBO	Emitter-Base Voltage (IC = 0)	6	V
IC	Collector Current	100	mA
Ptot	Total Dissipation at Tamb ≤ 25°C / at TC ≤ 25°C	0.3 / 0.75	W / W
Tstg	Storage Temperature	-55 to 175	°C
Tj	Max. Operating Junction Temperature	175	°C

BC107 Applications

Common Uses in Electrical Drivers

The BC107 transistor is widely used in various driver applications, such as relay and LED drivers. In many electronic systems, it plays a role in switching and control functions. When used in relay drivers, the BC107 enables the actuation of switches without requiring a high power input. In LED driver circuits, it helps regulate current to ensure stable and efficient illumination. For example, in modern vehicles and consumer electronics, reliable transistors like the BC107 are often used to optimize LED brightness and performance.

Amplification in Audio and Signal Systems

The BC107 performs effectively in amplifier circuits, where it amplifies weak signals for enhanced audio and signal quality. It is commonly found in home audio systems and sound engineering applications, where maintaining sound fidelity and clear signal transmission is crucial for delivering a high-quality auditory experience.

Integration into Darlington Pairs

The BC107 is often integrated into Darlington pair configurations to achieve a higher current gain. This setup is highly efficient for high-load switching applications, making it useful in industrial automation systems that require reliable and efficient transistor switching.

Signal Processing Capabilities

The BC107 excels in signal processing tasks such as filtering, modulation, and amplification. Its capabilities are particularly useful in communication devices, where it ensures signal clarity and strength, which are necessary for effective transmission and reception.

Power Management Applications

In power management circuits, the BC107 plays a role in regulating voltage and current to keep devices operating within safe limits. This is especially beneficial for battery-operated devices, as it helps extend their operational life by using power efficiently. Devices like tools and compact electronics often rely on such power regulation mechanisms.

Usefulness in Portable Gadgets

The BC107’s adaptability makes it suitable for use in portable gadgets that need lightweight and efficient components. Due to its compact size and reliable performance, it is frequently used in portable medical devices, ensuring functionality and dependability even under varying power conditions.

Presence in Consumer Electronics

The BC107 is widely used in consumer electronics, from smartphones to household appliances. It contributes to the stable and efficient operation of these devices, demonstrating its reliability and consistency in supporting the seamless performance of today’s technology.

Industrial Utilization

In industrial applications, the BC107 is valued for its robustness and reliability. Industrial machinery and control systems use it for various tasks, ranging from basic switching to complex signal modulation and amplification. Its ability to withstand demanding conditions makes it an essential component in these settings.

Mechanical Data for BC107

Manufacturer Information for BC107

The BC107 transistor is produced by STMicroelectronics, a major global player in the semiconductor industry. Headquartered in Plan-les-Ouates near Geneva, Switzerland, the company was formed in 1987 through the merger of Thomson Semiconducteurs (France) and SGS Microelettronica (Italy). This merger brought together their expertise, establishing STMicroelectronics as a leader in semiconductor technology.

STMicroelectronics has a strong global presence, with its main administrative centers located strategically around the world. The EMEA (Europe, Middle East, and Africa) Headquarters are in Geneva, the US Headquarters are in Texas, the APAC (Asia-Pacific) Headquarters are in Singapore, and the Japan and Korea Headquarters are in Tokyo. Its China Headquarters are in Shanghai, further extending its reach into key markets. This global footprint helps the company efficiently meet customer needs across different regions.

As Europe’s top semiconductor manufacturer by revenue, STMicroelectronics provides solutions that cater to a wide range of industries, including automotive, industrial, personal electronics, and telecommunications. Their products are known to enhance efficiency and performance, driving innovation in these fields.

The company’s success is built on its strong commitment to research and development. With significant investments in R&D, STMicroelectronics consistently develops cutting-edge solutions in areas like analog and mixed-signal technology, digital electronics, MEMS (Micro-Electro-Mechanical Systems), and power management.

Looking ahead, STMicroelectronics plans to continue leading the market by adapting to emerging technologies and trends. Their focus on sustainable development aligns with global environmental goals, promoting renewable energy solutions and intelligent mobility. This forward-thinking approach positions the company to address future challenges while maintaining its influence in the semiconductor industry.

Frequently Asked Questions [FAQ]

1. What does "BC" in BC107 stand for?

"B" stands for Silicon Transistor, and "C" represents that it operates in the audio frequency range.

2. Is BC107 the same as BC547?

The BC107 and BC547 are both NPN bipolar transistors. The BC547 is a modern replacement for the BC107, with the main difference being in their packaging. They have similar electrical characteristics, including the same breakdown voltage, and the BC547 has a slightly better cutoff frequency. The current gain ranges are almost the same, making the BC547 a likely one-to-one substitute for the BC107.

3. What do the numbers "107" represent in BC107?

The "107" is a serial number that helps identify specific parameters found in the datasheet for the BC107 transistor.