S9018 Transistor J8 NPN 18V 50mA 200mW TO-92

S9018 Transistor J8 is a general-purpose NPN transistor used for low-power amplification and switching applications. With a collector current of 50mA and power dissipation up to 200mW, it’s ideal for audio frequency signal amplification and small load control circuits. Packaged in a TO-92 form factor, it is commonly used in consumer electronics and DIY electronic projects.

Key Features:

• General-Purpose NPN Transistor: Suitable for low-power amplification and switching.
• Compact TO-92 Package: Ideal for breadboard and PCB mounting.
• Moderate Gain: DC current gain (hFE) typically around 100 to 300.
• Fast Switching Speed: Suitable for signal processing circuits.
• Low Saturation Voltage: Ensures efficient switching performance.

Technical Specifications:

• Transistor Type: NPN
• Collector-Base Voltage (VCBO): 30V
• Collector-Emitter Voltage (VCEO): 18V
• Emitter-Base Voltage (VEBO): 5V
• Collector Current (IC): 50mA
• Power Dissipation (Ptot): 200mW
• DC Current Gain (hFE): 100–300 at IC = 1mA, VCE = 6V
• Transition Frequency (fT): 150MHz (typical)

Mechanical Specifications:

• Package Type: TO-92 (plastic case)
• Lead Configuration: Emitter–Base–Collector (E-B-C from left to right, flat side facing)
• Body Dimensions: Approx. 4.5mm × 4.0mm × 5.0mm
• Lead Pitch: 1.27mm (typical)

Mounting Options:

• Through-Hole Mount: Designed for standard breadboard and PCB layouts.
• Solderable Leads: Suitable for wave and hand soldering processes.

Schematic Diagram, Connection, Wiring and Pinout:

• Pin Configuration: Emitter (left), Base (center), Collector (right)
• Wiring: Connect base via a current-limiting resistor; collector to load; emitter to ground.
• Symbol: Standard NPN transistor symbol in circuit diagrams.

Datasheet and Documentation:

• Download S9018 Datasheet (PDF)

Applications:

• Signal Amplification: Used in preamplifiers and audio stages.
• Switching Circuits: Suitable for relay and small load switching.
• Oscillators and Timers: Used in low-frequency generation circuits.
• RF Circuits: Performs well in high-frequency signal processing.
• DIY Projects: Common choice for students and electronics hobbyists.

Equivalent Models:

• 2N3904: Widely used NPN transistor with similar ratings
• BC547: General-purpose NPN alternative for low-current applications
• 2SC945: Japanese equivalent with comparable specs

Package Includes:

• 1 x S9018 Transistor J8 NPN 18V 50mA 200mW TO-92