BD707 Pinout, Equivalent, Applications, Datasheet

The BD707 is an NPN silicon power transistor designed for high current and medium voltage applications. With a collector current up to 12A and a collector-emitter voltage of 60V, this transistor is ideal for power amplification, switching, and motor driver circuits. Housed in a TO-220 package, the BD707 ensures efficient heat dissipation and pairs perfectly with its complementary PNP transistor, BD708 with the same pinout.

Introduction to BD707 NPN Transistor

The BD707 belongs to the BD700 transistor family, a popular series of silicon-based power transistors designed for efficient performance in high-current amplification and switching applications. The BD707 is an NPN power transistor, meaning it conducts current when a small base current flows into the base terminal.

Its rugged construction and excellent electrical characteristics make it suitable for general-purpose medium-power amplifiers, voltage regulators, and motor control circuits. The BD707 is also known for its low saturation voltage, high DC gain, and strong thermal stability, ensuring reliable operation under demanding conditions.

With a collector current capacity of 12A and maximum collector-emitter voltage of 45V, it serves as a durable choice for power electronics applications.

BD707 NPN Transistor

Pinout of BD707

Understanding the BD707 Pinout Configuration

The BD707 comes in the TO-220 package, a well-known standard for power transistors that provides good heat dissipation and ease of mounting. The transistor’s leads are arranged for easy identification and connection in circuits.

Pin Configuration of BD707 Pinout

Pin Orientation: When facing the flat side of the transistor with the leads pointing downward, the order from left to right is Base – Collector – Emitter.

Key Features of BD707 Transistor

• NPN silicon power transistor
• Collector current up to 12A
• Collector-emitter voltage of 60V
• Power dissipation up to 75W
• High current gain with stable performance
• Low collector-emitter saturation voltage
• Complementary to BD708 PNP transistor
• Suitable for high-current amplifier stages and switch control
• Excellent heat transfer capability in TO-220 package

BD707 Transistor Datasheet and Specifications

• Collector-Emitter Voltage (VCEO): 60V
• Collector-Base Voltage (VCBO): 60V
• Emitter-Base Voltage (VEBO): 5V
• Collector Current (IC): 12A
• Power Dissipation (PC): 75W (at Tc = 25°C)
• DC Current Gain (hFE): 40 (minimum at IC = 0.5A)
• Collector-Emitter Saturation Voltage (VCEsat): Max 1.0V at 4A
• Transition Frequency (fT): 3 MHz (typical)
• Junction Temperature (Tj): 150°C (maximum)
• Thermal Resistance (RθJC): 1.67°C/W

The BD707 provides a robust balance between current handling and thermal management, making it ideal for medium-power circuit designs.

Working Principle of BD707 NPN Transistor

The BD707 transistor operates based on current amplification. When a small base current is applied to the transistor, it allows a much larger current to flow between the collector and emitter.

As an NPN transistor, it conducts when the base is biased positively relative to the emitter. The current amplification property makes it useful in amplifier circuits, while its switching speed and power handling capability make it reliable for control circuits and power regulators.

In amplifier configurations, the BD707 operates in the active region, whereas in switching circuits, it alternates between saturation (ON) and cutoff (OFF) states for efficient power control.

More Circuit Layouts

Typical Applications of BD707

• Audio amplifier output stages
• DC motor driver circuits
• Power regulation and voltage control
• Switching power supplies and inverters
• Relay and solenoid drivers
• Industrial automation and control boards
• Complementary pair amplifier designs with BD708

PNP Complementary Transistor

The complementary transistor of BD707 is the BD708, a PNP silicon power transistor designed with matching electrical ratings. When paired together, BD707 and BD708 form a balanced push-pull configuration that enhances output symmetry and reduces distortion in audio and power amplifier circuits.

This complementary pairing is widely used in amplifier design, motor control systems, and high-efficiency switching circuits.

Equivalent Transistors and Alternatives

• BD705
• BD709
• 2N6488
• TIP31C
• MJE3055
• 2SD313

When choosing an equivalent for BD707, make sure to verify the collector-emitter voltage, current rating, gain, and pinout to ensure compatibility with your circuit design.

Comparison BD707 vs BD708 Complementary Transistors

The BD707 and BD708 are complementary transistors forming an NPN-PNP pair suitable for push-pull stages in amplifier and power circuits. Both share identical ratings of 45V collector-emitter voltage and 12A collector current.

The BD707 (NPN) requires a positive base bias, while BD708 (PNP) requires a negative base bias. This opposite polarity enables them to operate together efficiently, ensuring symmetrical waveform amplification and power delivery. The pair is particularly valued for its linear performance, durability, and low crossover distortion in output stages.

Frequently Asked Questions (FAQ)

What is the BD707 transistor used for?

The BD707 is mainly used for power amplification, switching, and DC motor control applications.

What type of transistor is BD707?

It is an NPN silicon power transistor available in a TO-220 package.

What is the BD707 pin configuration?

Pin 1 is Base, Pin 2 is Collector, and Pin 3 is Emitter.

What is the complementary transistor for BD707?

The complementary PNP transistor is the BD708.

Can I use BD705 instead of BD707?

Yes, BD705 can be used in some circuits if the voltage and current ratings meet your design requirements, but confirm the pin layout before substitution.

Conclusion

The BD707 NPN transistor is a highly reliable device that provides excellent performance in both amplifier and switching applications. With a 45V collector-emitter voltage, 12A current capability, and 75W power dissipation, it is perfectly suited for medium to high-power control systems.

Its compatibility with BD708 as a complementary pair makes it ideal for push-pull and audio output circuits. With strong thermal stability, consistent current gain, and broad availability, the BD707 remains a dependable choice for engineers and electronics enthusiasts alike.

Datasheet of BD707 NPN Transistor

Click the following Button to download the datasheet of BD707 Transistor :

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