Infineon Technologies SMBT3904B5000

Overview

SMBT3904B5000 from Nexperia is a dual NPN silicon switching transistor in SOT363 (SC-74) package, featuring two galvanically isolated transistors with matched characteristics for differential or push-pull operation. It delivers V_CEO = 40 V, I_C = 200 mA per transistor, h_FE = 100–300 at I_C = 10–100 mA, and V_CE(sat) ≤ 0.3 V at I_C = 50 mA / I_B = 5 mA - used in automotive signal conditioning and industrial logic-level interface circuits.

For engineers reviewing the SMBT3904B5000 datasheet, SMBT3904B5000 pinout, SMBT3904B5000 application, or SMBT3904B5000 equivalent, key selection criteria include dual-transistor matching tolerance, AEC-Q101 qualification status, thermal resistance R_thJS = 140 K/W, and low V_CE(sat) under 100 mA switching loads.

Technical Context

This device implements two independent NPN bipolar junction transistors in a single SOT363 package with electrically isolated collectors, bases, and emitters - enabling matched-pair operation without cross-coupling. Its design supports high-speed switching (f_T = 300 MHz) and low-noise amplification (F = 5 dB at 1 kHz), with guaranteed h_FE stability across I_C = 0.1–100 mA.

The SMBT3904B5000 meets AEC-Q101 stress testing for automotive use, including temperature cycling, HTRB, and ESD robustness. Its thermal performance is characterized by R_thJS ≤ 140 K/W and P_tot = 250 mW at T_S ≤ 105°C, supporting reliable operation in space-constrained PCB layouts with moderate power dissipation.

Key Specifications

Pinout & Package

Package: SOT363 (SC-74), 6-pin surface-mount plastic package with gull-wing leads and exposed thermal pad (not electrically connected). Dimensions: 2.1 mm × 2.0 mm × 1.0 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-NPN switching transistor applications.

Compared with BC847BDW1T1G, SMBT3904B5000 offers superior thermal robustness and automotive qualification; versus DMN3026LSD-13, it provides current-controlled switching with predictable base current requirements and lower gate-drive complexity.

Availability

SMBT3904B5000 is available at Aetrix Electronics and suitable for automotive body electronics, industrial programmable logic controllers, and medical sensor signal conditioning requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SMBT3904B5000 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Nexperia is a global semiconductor expert focused on high-volume, high-reliability discrete and logic devices, with leadership in automotive-qualified components and energy-efficient packaging.

The SMBT3904 series belongs to Nexperia's AEC-Q101-qualified bipolar transistor portfolio, engineered specifically for robust signal switching and amplification in harsh-environment automotive and industrial control systems.

FAQ

What is the maximum junction temperature rating for SMBT3904B5000?

The absolute maximum junction temperature (T_j) is 150°C, verified per AEC-Q101 test conditions. Operation above this limit risks permanent degradation of h_FE and increased leakage. Derating curves in the datasheet show P_tot must be reduced linearly above T_S = 105°C to maintain safe T_j.

Does SMBT3904B5000 support DC-coupled differential pair configurations?

Yes - its galvanically isolated transistor structure allows true DC-coupled differential operation without shared collector or emitter nodes. The matched h_FE and V_BE ensure <±5 mV offset in emitter-coupled pairs at I_C = 1 mA, enabling stable biasing without external trimming resistors.

How does the SOT363 package affect thermal performance compared to SOT23?

The SOT363 package provides lower R_thJS (140 K/W) than standard SOT23 (245 K/W) due to doubled thermal pad area and optimized internal die attach. This allows 250 mW dissipation at T_S = 105°C - 33% higher than equivalent SOT23-packaged 3904 variants under identical board conditions.

Can SMBT3904B5000 replace single-transistor MMBT3904 in existing designs?

No - SMBT3904B5000 is a dual-transistor device with 6-pin SOT363 layout and non-interchangeable pinout. Direct replacement requires PCB redesign to accommodate separate base/emitter/collector connections for both transistors and verify layout spacing for thermal pad clearance.