BF247C N-Channel Junction Field-Effect Transistor (JFET)

Overview

The BF247C is a general-purpose N-channel symmetrical silicon junction field-effect transistor (JFET) housed in a plastic TO-92 package. This device is designed for applications requiring high-frequency performance, low noise, and excellent linearity. The symmetrical nature of the drain and source connections allows for interchangeability, providing flexibility in circuit design. The BF247C is supplied in an antistatic package to prevent damage from electrostatic discharge (ESD), ensuring reliability during handling and assembly.

This JFET is well-suited for amplification and switching applications in audio, RF, and analog circuits. Its high IDSS (zero-gate-voltage drain current) range and frequency capabilities make it a versatile choice for designers seeking stable performance in a compact package.

Features

• Symmetrical Drain and Source: Interchangeable connections for design flexibility.
• High IDSS Range: Ensures robust performance in various biasing conditions.
• High-Frequency Operation: Suitable for applications up to 450 MHz.
• Low Noise: Ideal for sensitive amplification stages in audio and RF circuits.
• TO-92 Package: Compact and widely compatible with through-hole PCB designs.
• Antistatic Packaging: Protects the device from electrostatic discharge during handling.

Applications

The BF247C is widely used in electronic circuits where high input impedance, low noise, and high-frequency performance are required. Key applications include:

• RF Amplifiers: Low-noise amplification in radio frequency circuits.
• Audio Preamplifiers: High-impedance input stages for microphone and instrument amplification.
• Analog Switches: Signal routing in audio and communication systems.
• Oscillators: Stable frequency generation in RF and test equipment.
• Impedance Buffers: Isolation between high and low impedance circuit stages.

Electrical Characteristics

The following tables outline the key electrical specifications of the BF247C under typical operating conditions (unless otherwise specified).

Absolute Maximum Ratings

• Drain-Source Voltage (V_DS): 30 V
• Gate-Source Voltage (V_GS): ±30 V
• Drain Current (I_D): 30 mA
• Total Power Dissipation (P_tot): 350 mW
• Operating Temperature Range (T_op): -55°C to +150°C
• Storage Temperature Range (T_stg): -55°C to +150°C

Typical Electrical Characteristics (T_A = 25°C)

• Zero-Gate-Voltage Drain Current (I_DSS): 6 mA to 20 mA (V_DS = 15 V, V_GS = 0 V)
• Gate-Source Cutoff Voltage (V_GS(off)): -0.5 V to -6 V (I_D = 10 µA, V_DS = 15 V)
• Forward Transconductance (g_fs): 3.5 mS to 7 mS (V_DS = 15 V, I_D = 1 mA, f = 1 kHz)
• Input Capacitance (C_iss): 4 pF (V_DS = 15 V, V_GS = 0 V, f = 1 MHz)
• Output Capacitance (C_oss): 2 pF (V_DS = 15 V, V_GS = 0 V, f = 1 MHz)
• Reverse Transfer Capacitance (C_rss): 1.5 pF (V_DS = 15 V, V_GS = 0 V, f = 1 MHz)
• Noise Figure (NF): 2 dB (V_DS = 15 V, I_D = 1 mA, f = 1 kHz)

Package Information

The BF247C is available in a standard TO-92 plastic package, which is widely used for through-hole mounting. The package dimensions and pin configuration are as follows:

TO-92 Package Dimensions

• Body Length: 4.95 mm (max)
• Body Width: 3.94 mm (max)
• Body Height: 4.95 mm (max)
• Lead Diameter: 0.46 mm (nominal)
• Lead Spacing: 2.54 mm (between pins)

Pin Configuration

• Pin 1: Drain (D)
• Pin 2: Gate (G)
• Pin 3: Source (S)

Note: Due to the symmetrical nature of the JFET, the drain and source pins (1 and 3) are interchangeable in most applications.

Handling and Storage

To ensure optimal performance and longevity of the BF247C, adhere to the following handling and storage guidelines:

• Always use ESD-safe handling procedures, including grounded workstations and wrist straps.
• Store in antistatic packaging when not in use.
• Avoid exposure to excessive moisture; store in a dry environment.
• Do not exceed the absolute maximum ratings during operation or testing.

Conclusion

The BF247C N-channel JFET is a versatile and reliable component for high-frequency, low-noise applications. Its symmetrical design, robust electrical characteristics, and compact TO-92 package make it an excellent choice for audio, RF, and analog circuit designs. By following proper handling and operating guidelines, designers can leverage the BF247C's performance in a wide range of electronic systems.