Diodes Inc. MMBT3904-7-F NPN SOT-23 Transistor, 40V 200mA

The Diodes Inc. MMBT3904-7-F is a robust and versatile NPN bipolar junction transistor (BJT) housed in a compact SOT-23 surface-mount package. Engineered for reliability, this general-purpose device is an excellent choice for medium-power amplification and switching applications across a wide range of electronic circuits.

With a maximum collector-emitter voltage (Vce) of 40V and a continuous collector current (Ic) rating of 200mA, it offers a solid balance of performance and efficiency. A key feature is its high transition frequency (ft) of 300MHz minimum, ensuring excellent high-frequency response suitable for RF and fast-switching scenarios. The transistor also boasts a low collector-emitter saturation voltage (Vce(sat)) of just 0.20V maximum, which minimises power loss and heat generation when the device is fully switched on.

Key Performance Characteristics

• High Voltage Tolerance: Collector-base breakdown voltage is rated at a minimum of 60V.
• Low Leakage: Features a very low collector cut-off current of 50nA maximum.
• Excellent Gain: Provides a DC current gain (hFE) of 100, ensuring effective signal amplification.
• Fast Switching: Offers quick rise and fall times of 35ns and 50ns maximum respectively, ideal for digital logic and pulse applications.
• Low Noise: A noise figure of 5.0dB maximum makes it suitable for sensitive audio and communication front-ends.
• Wide Temperature Range: Operates reliably across an extensive temperature range from -55°C to +150°C.

Encased in the industry-standard SOT-23 package, this transistor is designed for automated assembly and is perfect for space-constrained printed circuit board (PCB) designs. It is a fundamental component for designers and engineers building amplifiers, drivers, interface circuits, and logic buffers.