BC856 PNP Transistor Technical Summary

Overview

The BC856 is a general-purpose PNP bipolar junction transistor (BJT) housed in an SC-75 plastic package. Designed for low-power amplification and switching applications, this transistor is characterized by its low current and voltage ratings, making it suitable for a variety of electronic circuits. Its compact form factor and reliable performance make it a popular choice among designers for space-constrained applications.

Features

• Low Current Handling: Maximum collector current (I_C) of 100 mA, ideal for low-power circuits.
• Low Voltage Operation: Maximum collector-emitter voltage (V_CEO) of 65 V, suitable for low-voltage applications.
• Compact Package: SC-75 (SOT-416) surface-mount package, enabling high-density PCB designs.
• High Current Gain: Offers good amplification capabilities with typical h_FE values in the range of 110 to 800, depending on operating conditions.
• Low Saturation Voltage: Ensures efficient switching performance with minimal power loss.
• RoHS Compliant: Manufactured with environmentally friendly materials, adhering to global environmental standards.

Applications

The BC856 PNP transistor is widely used in various electronic circuits due to its versatile characteristics. Below are some common applications:

• Signal Amplification: Used in audio amplifiers, sensor interfaces, and other low-power signal conditioning circuits.
• Switching Circuits: Suitable for driving relays, LEDs, and other low-current loads in switching applications.
• Oscillators and Waveform Generators: Employed in feedback circuits for generating stable oscillations.
• Voltage Regulation: Used in conjunction with other components to create simple voltage regulator circuits.
• Consumer Electronics: Found in portable devices, remote controls, and other battery-operated systems.
• Industrial Control Systems: Used in control logic circuits and low-power automation systems.

Electrical Characteristics

The following tables outline the key electrical specifications of the BC856 PNP transistor under typical operating conditions (unless otherwise specified).

Absolute Maximum Ratings

• Collector-Emitter Voltage (V_CEO): 65 V
• Collector-Base Voltage (V_CBO): 80 V
• Emitter-Base Voltage (V_EBO): 5 V
• Collector Current (I_C): 100 mA
• Total Power Dissipation (P_tot): 250 mW
• Operating Junction Temperature (T_j): -55°C to +150°C
• Storage Temperature (T_stg): -55°C to +150°C

Typical Electrical Characteristics (T_A = 25°C)

• DC Current Gain (h_FE): 110 to 800 (at I_C = 2 mA, V_CE = 5 V)
• Collector-Emitter Saturation Voltage (V_CE(sat)): 0.25 V (max) (at I_C = 10 mA, I_B = 1 mA)
• Base-Emitter Saturation Voltage (V_BE(sat)): 0.9 V (max) (at I_C = 10 mA, I_B = 1 mA)
• Transition Frequency (f_T): 100 MHz (typical) (at I_C = 10 mA, V_CE = 5 V)
• Output Capacitance (C_obo): 4 pF (typical) (at V_CB = 10 V, f = 1 MHz)

Package Information

The BC856 is available in an SC-75 (SOT-416) surface-mount package, which is designed for automated assembly processes. Below are the key mechanical specifications:

SC-75 (SOT-416) Package Dimensions

• Package Length: 1.6 mm (max)
• Package Width: 1.2 mm (max)
• Package Height: 0.6 mm (max)
• Lead Pitch: 0.65 mm (typical)
• Termination: Tin-plated leads for reliable solderability.

Recommended PCB Footprint

For optimal performance and manufacturability, the following PCB footprint is recommended:

• Pad Dimensions: 0.8 mm x 0.6 mm (for each of the three terminals).
• Spacing: 0.65 mm between pad centers.
• Thermal Considerations: A small thermal pad or copper pour may be used to dissipate heat in high-duty-cycle applications.

Conclusion

The BC856 PNP transistor is a versatile and reliable component for low-power amplification and switching applications. Its compact SC-75 package, combined with robust electrical characteristics, makes it an excellent choice for modern electronic designs. Whether used in consumer electronics, industrial controls, or signal processing circuits, the BC856 delivers consistent performance while adhering to environmental standards.