The 2N5457 is an industry-standard, general-purpose N-Channel Junction Field-Effect Transistor (JFET) encapsulated in a compact TO-92 plastic through-hole package. Engineered specifically for high-gain, low-noise audio amplification, analog signal switching, and high-impedance buffer stages, the 2N5457 features an extremely high input impedance, low inter-electrode capacitances, and low harmonic distortion. It is widely used in guitar pedals, audio preamplifiers, microphone buffers, analog synthesizers, and precision instrumentation.

Specifications

• Brand / Manufacturer: Central Semiconductor / ON Semiconductor / Fairchild / Industry Standard
• Part Number: 2N5457
• Transistor Type: N-Channel Depletion-Mode JFET
• Drain-Source Voltage (V_DS): 25V
• Drain-Gate Voltage (V_DG): 25V
• Gate-Source Reverse Breakdown Voltage (V_GSR): -25V
• Gate-Source Forward Voltage (V_GSF): 10V
• Gate Current (I_G): 10mA
• Zero-Gate-Voltage Drain Current (I_DSS): 1.0mA to 5.0mA (at V_DS = 15V, V_GS = 0V)
• Gate-Source Cutoff Voltage (V_GS(off)): -0.5V to -6.0V (at V_DS = 15V, I_D = 10nA)
• Forward Transconductance (|Y_fs| / g_fs): 1000µS to 5000µS (at V_DS = 15V, V_GS = 0V, f = 1.0kHz)
• Drain-Source On-Resistance (r_ds(on)): Typically 200Ω to 400Ω (at V_GS = 0V)
• Common-Source Input Capacitance (C_iss): Max 7.0pF (at V_DS = 15V, V_GS = 0V, f = 1.0MHz)
• Common-Source Reverse Transfer Capacitance (C_rss): Max 3.0pF (at V_DS = 15V, V_GS = 0V, f = 1.0MHz)
• Total Device Dissipation (P_D): 310mW (at T_A = 25°C)
• Operating Junction & Storage Temperature Range: -55°C to +150°C
• Package / Case: TO-92 (3-Pin Through-Hole: Pin 1: Drain, Pin 2: Source, Pin 3: Gate)

Features

• Ultra-High Input Impedance: High gate isolation prevents loading on high-impedance audio transducers, guitar pickups, and sensitive sensor circuits.
• Low Distortion & Clean Linearity: Provides smooth, warm analog amplification characteristics, making it highly desirable for audio effects and preamplification.
• Low Noise Operation: Minimizes background hiss and thermal noise in weak-signal input stages.
• Symmetrical Depletion-Mode Channel: Can operate in bidirectional analog switching and voltage-controlled resistance (VCR) circuits.
• Standard TO-92 Footprint: Breadboard and perfboard friendly, perfect for audio prototyping, DIY synthesizers, and replacement in vintage analog gear.

Common Applications

• Guitar Effects & Pedals: High-impedance input buffers, overdrive stages, boost pedals, and analog phase shifters.
• Audio Preamplifiers: Low-noise preamplification for condenser microphones, piezo transducers, and magnetic pickups.
• High-Impedance Buffer Stages: Unity-gain source followers for audio mixing consoles and active instrument circuitry.
• Analog Signal Switching & Muting: Click-free audio signal muting, routing, and chopper circuits.
• Voltage-Controlled Resistors (VCR): Gain control and variable attenuation in automatic gain control (AGC) and compressor circuits.

Usage Tips

• Pinout Configuration: Looking at the flat marked front of the TO-92 package with leads pointing downward, the standard pinout is Pin 1: Drain (D), Pin 2: Source (S), and Pin 3: Gate (G). (Note: In symmetrical JFETs, Drain and Source can be functionally swapped, but standard orientation is recommended for consistent parasitic layout).
• Self-Biasing Topology: To bias the 2N5457 as a linear audio amplifier, use a source self-bias resistor (R_S, typically 1kΩ to 3.3kΩ) bypassed with an electrolytic capacitor to establish a negative gate-to-source bias without requiring a separate negative power supply.
• Gate DC Path Requirement: Always provide a high-value gate ground reference resistor (such as 1MΩ to 10MΩ) to ensure a DC return path and prevent gate floating.
• Handling & ESD Precautions: Handle using standard ESD safety practices to prevent static gate-oxide puncture and junction degradation.

Datasheet