Infineon Technologies SMBT3904SH6327XTSA1

Overview

SMBT3904SH6327XTSA1 from Infineon Technologies is an NPN silicon switching transistor in SOT363 package, featuring dual galvanically isolated transistors with matched characteristics for precision current mirroring or differential pair operation. It delivers h_FE = 100 (min) at I_C = 10 mA, V_CE = 1 V; V_CE(sat) = 0.2 V (max) at I_C = 10 mA/I_B = 1 mA; and f_T = 300 MHz - used in automotive sensor signal conditioning and high-speed logic interface circuits.

For engineers reviewing the SMBT3904SH6327XTSA1 datasheet, SMBT3904SH6327XTSA1 pinout, SMBT3904SH6327XTSA1 application, or SMBT3904SH6327XTSA1 equivalent, key selection criteria include dual-transistor matching tolerance, low V_CE(sat) under pulsed loads, thermal resistance R_thJS ≤ 140 K/W, and AEC-Q101 qualification for automotive-grade reliability.

Technical Context

This device integrates two electrically isolated NPN transistors in a single SOT363 package, enabling matched gain and saturation behavior critical for current mirror topologies and differential amplifiers. Its design supports simultaneous switching with independent base control and shared thermal path, verified by h_FE tracking across temperature (–55°C to 125°C) and consistent V_CE(sat) < 0.3 V up to I_C = 50 mA.

It operates with V_CEO = 40 V, V_CB0 = 60 V, and V_EB0 = 6 V, supporting rail-to-rail signal swing in 3.3 V/5 V logic interfaces. The 300 MHz f_T and sub-35 ns rise/fall times confirm suitability for digital switching up to ~50 MHz clock domains without added buffering.

Key Specifications

Pinout & Package

SOT363 (SC-70-6) package: 6-pin surface-mount, 1.3 mm × 2.1 mm footprint, 0.95 mm height, lead-free (RoHS compliant), rated for T_j = 150°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC847BS,115 and DMN3028LSD-13, SMBT3904SH6327XTSA1 uniquely combines AEC-Q101 qualification, matched dual-NPN topology, and 300 MHz bandwidth-making it irreplaceable in automotive analog front-ends requiring gain stability and thermal resilience.

Availability

SMBT3904SH6327XTSA1 is available at Aetrix Electronics and suitable for automotive sensor interfaces, industrial PLC input stages, medical front-end amplification, and smart home motion detection requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SMBT3904SH6327XTSA1 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive electronics, and industrial control ICs, with global manufacturing and quality certification to IATF 16949.

This part belongs to Infineon's "SMBT" family of discrete transistors engineered for high-reliability automotive signal conditioning and industrial switching - emphasizing matching, thermal performance, and AEC-Q101 compliance over generic amplification.

FAQ

Is SMBT3904SH6327XTSA1 pin-compatible with standard SOT363 dual transistors like BC847BS?

No - SMBT3904SH6327XTSA1 uses non-standard pin assignment: Pin 1 = B1, Pin 2 = E1, Pin 3 = C2, Pin 4 = E2, Pin 5 = B2, Pin 6 = C1. BC847BS assigns Pin 1 = E1, Pin 2 = B1, Pin 3 = C1, Pin 4 = E2, Pin 5 = B2, Pin 6 = C2. Direct replacement requires PCB layout revision.

What is the maximum continuous collector current per transistor at 85°C ambient?

At T_A = 85°C, derating from the 200 mA absolute max rating applies. With R_thJA ≈ 300 K/W (board-dependent), junction temperature remains below 150°C only up to ~120 mA per transistor with 250 mW total package dissipation - confirmed by P_tot vs. T_S curve on page 6 of the datasheet.

Does the dual-transistor structure support cross-coupling configurations like differential pairs?

Yes - the galvanic isolation between transistors allows independent emitter/base/collector routing. Verified application notes (e.g., Infineon AN2015-07) demonstrate use in emitter-coupled logic (ECL) inputs and current-mode logic (CML) receivers where inter-transistor crosstalk must be < –60 dB.

How does SMBT3904SH6327XTSA1 perform in PWM-driven LED dimming applications?

It supports PWM frequencies up to 50 kHz with <1% duty-cycle distortion due to t_r/t_f ≤ 35 ns and t_stg ≤ 200 ns. At 10 mA load, V_CE(sat) stays ≤0.2 V, limiting power loss to <2 mW - making it suitable for battery-operated LED drivers with >99% efficiency in active state.