Infineon BC847PN NPN General-Purpose Amplifier Transistor: Datasheet, Pinout, and Application Circuits
The Infineon BC847PN is a widely used NPN bipolar junction transistor (BJT) belonging to the family of general-purpose amplification and switching devices. Housed in a compact SOT-363 (SC-88) package, it contains two identical, separately connected transistors, making it an excellent choice for space-constrained applications requiring matched pairs or complementary circuits. Its high current gain and low noise characteristics make it a versatile component in modern electronics.
Datasheet Overview and Key Specifications
The BC847PN is designed for general-purpose amplification and switching applications. Key maximum ratings from its datasheet include a collector-emitter voltage (VCE) of 45 V, a collector current (IC) of 100 mA, and a total power dissipation (Ptot) of 250 mW. Its electrical characteristics are notable for a high DC current gain (hFE), which ranges from 200 to 450 at a collector current of 2 mA, ensuring significant signal amplification. The transition frequency is 250 MHz, making it suitable for a wide range of low to medium-frequency applications.
Pinout Configuration
The BC847PN comes in a SOT-363 surface-mount package. The pinout configuration for the dual transistor is as follows:
Pin 1 (Emitter 1): Emitter of the first transistor.
Pin 2 (Collector 1): Collector of the first transistor.
Pin 3 (Base 1): Base of the first transistor.
Pin 4 (Base 2): Base of the second transistor.
Pin 5 (Collector 2): Collector of the second transistor.
Pin 6 (Emitter 2): Emitter of the second transistor.
It is crucial to consult the datasheet for the exact pinout diagram to ensure correct PCB layout and orientation.
Common Application Circuits
1. Common-Emitter Amplifier: This is the most classic application for amplification. A small AC signal applied to the base (through a coupling capacitor) is amplified to a larger signal at the collector. Proper biasing resistors are required to set the transistor's operating point in the active region for linear signal amplification.
2. Current Mirror: Utilizing the dual, matched nature of the BC847PN, one transistor can be configured to set a reference current, which the second transistor will precisely mirror. This circuit is fundamental in providing stable bias currents within integrated circuits.
3. Differential Amplifier: The two transistors can be wired to form a differential pair, which amplifies the voltage difference between two input signals while rejecting any common-mode noise. This is a critical building block in operational amplifiers and analog signal processing.
4. High-Gain Darlington Pair: While typically built with two separate transistors, the BC847PN's dual structure allows for an integrated Darlington pair configuration. This connection offers an extremely high current gain (the product of the gains of the two transistors), ideal for driving higher-current loads like small relays or LEDs from a very low-current source.
5. Digital Switching: The transistor can be used as a simple switch. Applying a sufficient voltage to the base (typically >0.7V) saturates the transistor, allowing current to flow from collector to emitter, effectively turning a load "ON." A key advantage here is its fast switching speed, which is useful in digital logic interfaces.
ICGOODFIND: The Infineon BC847PN stands out as a highly reliable and versatile dual NPN transistor. Its combination of high current gain, compact dual packaging, and robust performance in both amplification and switching roles makes it a fundamental component for designers. Whether used in analog signal chains, bias circuits, or as a simple switch, it provides an efficient and space-saving solution for a vast array of electronic designs.
Keywords: NPN Transistor, General-Purpose Amplifier, SOT-363, High Current Gain, Switching Applications
