S9018 Transistor J8 NPN 18V 50mA 200mW TO-92
The S9018 is a general-purpose NPN bipolar junction transistor designed for low-power amplification and switching circuits. With a maximum collector current of 50mA and power dissipation up to 200mW, it is ideal for audio frequency signal amplification, RF signal processing, oscillators, timers, and small load control in DIY electronics and consumer projects. Packaged in a compact TO-92 through-hole case, it fits standard breadboards and PCBs.
Technical Specifications / Datasheet
| Parameter | Rating |
|---|---|
| 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) |
| Package Type | TO-92 |
| Lead Configuration | Emitter–Base–Collector (E-B-C from left, flat side facing) |
| Mounting Style | Through-hole |
Key Features
- General-purpose NPN transistor for low-power amplification and switching
- Compact TO-92 package, perfect for breadboard and PCB prototyping
- Moderate DC current gain (hFE) typically 100–300
- Fast switching speed for signal processing circuits
- Low saturation voltage for efficient switching
- Reliable performance in audio preamplifiers and RF circuits
Applications
- Signal amplification in preamplifiers and audio stages
- Small load switching and relay control
- Oscillators, timers, and low-frequency generators
- RF signal processing and high-frequency circuits
- DIY electronics, student projects, and hobbyist circuits
Pinout & Wiring
Pin Configuration (flat side facing you, pins down): Emitter (left), Base (center), Collector (right).
Basic wiring: connect the base through a current-limiting resistor, the collector to the load, and the emitter to ground.
Equivalent / Alternative 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