BC547 Transistor NPN 50V 100mA 625mW TO-92

BC547 Transistor NPN 50V 100mA 625mW TO-92 is a versatile, general-purpose silicon epitaxial planar NPN bi-polar junction transistor that serves as a cornerstone in modern electronic circuit design. This component excels at both low-noise amplification and high-speed switching tasks within a variety of consumer and industrial devices. Consequently, engineers and hobbyists frequently rely on the BC547 for its reliable gain characteristics and robust performance in low-power applications. Its high current gain and low saturation voltage make it an ideal candidate for driving small loads like LEDs, relays, and buzzers. Furthermore, the BC547 offers a cost-effective solution for signal processing without compromising on electrical stability. Therefore, you should consider this transistor an essential addition to any component toolkit for building everything from simple hobbyist projects to complex automated systems.

Key Features:

• High Current Gain: Features a DC current gain (h_FE) reaching up to 800, allowing for efficient amplification of weak input signals.
• Low Noise Figure: The device maintains a low noise profile, which makes it particularly suitable for pre-amplifier stages in audio circuits.
• Standard TO-92 Package: Utilizes a compact, through-hole plastic package that facilitates easy mounting on breadboards and PCBs.
• High Switching Speed: Operates efficiently in switching applications, transitioning between cutoff and saturation states with minimal delay.
• Robust Thermal Stability: The BC547 performs consistently across a wide temperature range, ensuring long-term reliability in varying environments.

Technical Specifications:

• Transistor Polarity: NPN
• Collector-Emitter Voltage (V_CEO): 45 V (Maximum)
• Collector-Base Voltage (V_CBO): 50 V (Maximum)
• Emitter-Base Voltage (V_EBO): 6.0 V (Maximum)
• Continuous Collector Current (I_C): 100 mA (Maximum)
• Total Power Dissipation (P_tot): 625 mW
• Transition Frequency (f_T): 300 MHz (Typical)
• Operating Junction Temperature Range: −65°C to +150°C

Mechanical Specifications:

• Package Type: TO-92 (Plastic-Encapsulated)
• Lead Style: Straight through-hole leads
• Lead Finish: Tinned Copper Alloy
• Weight: ≈ 0.18 g

Dimensions:

• Body Height: ≈ 4.58 mm
• Body Width (Flat Side): ≈ 4.58 mm
• Body Thickness: ≈ 3.86 mm
• Lead Length: ≈ 13.5 mm
• Lead Pitch: ≈ 1.27 mm

Pinout and Wiring:

• Pin 1 (Collector): Connect to the positive side of the load or the supply voltage in a switching circuit.
• Pin 2 (Base): Connect to the control signal or input signal via a current-limiting resistor to trigger the transistor.
• Pin 3 (Emitter): Connect to the circuit ground (GND) or common reference point.
• Wiring Note: Always verify the flat side of the TO-92 package to correctly identify the pins; however, pin configurations can occasionally vary between manufacturers, so double-check with a multimeter if unsure.

Datasheet Reference:

• Download ON Semiconductor BC547 Datasheet

Commonly Used in:

• Educational Kits: Used extensively in student electronics labs to demonstrate transistor logic and amplification.
• Audio Equipment: Frequently found in microphones and audio mixers as a low-noise pre-amplifier component.
• Logic Gates: Acts as a building block for creating discrete NOT, AND, and OR gates in digital logic experiments.

Applications:

• Relay Driving: Safely switches mechanical relays from low-power microcontroller pins.
• LED Switching: Controls high-brightness LEDs or LED strips in signal indicators and display panels.
• Signal Amplification: Boosts low-voltage signals from sensors to levels readable by ADCs or further processing stages.
• Touch Sensors: Serves as a highly sensitive switch in Darlington pair configurations for touch-activated circuits.

Equivalent Models:

• BC548 / BC549: These are very similar models within the same family, with the BC549 offering even lower noise characteristics.
• 2N3904: However, note that while the 2N3904 is a popular NPN equivalent, the pinout is reversed compared to the BC547.
• BC337: A higher current alternative (up to 800mA) that maintains a similar TO-92 footprint for more demanding loads.

Package Includes:

• 1 x BC547 Transistor NPN 50V 100mA 625mW TO-92