Diodes Incorporated BC846BQ-7-F

Overview

BC846BQ-7-F from Diodes Incorporated is an NPN small-signal transistor in SOT23 package, rated for 80 V_CBO, 65 V_CEO, and 100 mA continuous collector current, with DC current gain (h_FE) of 200–450 at I_C = 2 mA, used in low-power switching and audio-frequency amplification stages of industrial control interfaces and sensor signal conditioning circuits.

For engineers reviewing the BC846BQ-7-F datasheet, BC846BQ-7-F pinout, BC846BQ-7-F application, or BC846BQ-7-F equivalent, key selection criteria include V_CEO/V_CBO ratings, h_FE spread at 2 mA and 10 mA, V_CE(sat) at I_C/I_B = 10 mA/0.5 mA, thermal resistance (R_θJA = 403 °C/W), and automotive qualification status per AEC-Q101.

Technical Context

This transistor operates as a general-purpose NPN bipolar junction device optimized for linear amplification and digital switching in ambient temperatures from –65 °C to +150 °C. Its safe operating area supports pulsed collector currents up to 200 mA and DC dissipation up to 310 mW on minimum pad layout.

It exhibits f_T = 100–300 MHz at V_CE = 5 V, I_C = 10 mA, enabling use in RF preamplifier stages up to ~100 MHz. Input impedance (h_ie = 4.5 kΩ) and output admittance (h_oe = 30 µS) are specified under standard test conditions with 1 kHz AC signal superimposed on DC bias.

Key Specifications

Pinout & Package

BC846BQ-7-F is housed in a surface-mount SOT23 package (JEDEC TO-236AB), measuring 2.90 mm × 1.30 mm × 1.03 mm, with matte tin-plated leads compliant with MIL-STD-202 Method 208 solderability requirements.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN small-signal transistor applications.

Compared with BC846B-7-F, BC846BQ-7-F adds AEC-Q101 compliance and extended temperature validation, while MMBT3904-7-F trades voltage headroom for better thermal resistance on enhanced layouts-making each optimal for distinct reliability or thermal design constraints.

Availability

BC846BQ-7-F is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor signal chains, and consumer audio front-ends requiring stable component supply across multi-year production cycles.

Supply support for BC846BQ-7-F 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design centers across Asia and manufacturing in China, Taiwan, and Malaysia.

The BC846BQ series belongs to Diodes' AEC-Q101-qualified small-signal transistor product line, engineered specifically for automotive interior electronics, body control modules, and industrial equipment needing robustness across –40 °C to +125 °C ambient operation.

FAQ

What does the 'Q' suffix in BC846BQ-7-F signify?

The 'Q' denotes AEC-Q101 qualification, confirming that this variant has passed stress testing per JEDEC standards for automotive applications-including temperature cycling, humidity bias, and ESD robustness. It is not merely a marking variant but a separately tested and documented automotive-grade part with full traceability and PPAP support.

Can BC846BQ-7-F replace BC846B-7-F in existing designs?

Yes, electrically and mechanically-same SOT23 package, identical pinout, and matching absolute maximum ratings and electrical characteristics. However, BC846BQ-7-F adds automotive qualification documentation, lot traceability, and extended temperature validation, making it suitable for upgraded reliability requirements without hardware changes.

What is the maximum allowable PCB copper area for thermal optimization?

Per datasheet Note 6, mounting on 15 mm × 15 mm 1 oz copper reduces R_θJA from 403 °C/W to 357 °C/W, enabling 350 mW power dissipation. This area is defined as the total copper connected to the emitter and collector pads-not just thermal vias-and must be unbroken and exposed beneath the SOT23 footprint.

Is BC846BQ-7-F halogen-free and RoHS 3 compliant?

Yes-it uses a halogen- and antimony-free "Green" molding compound with <900 ppm bromine, <900 ppm chlorine, and <1000 ppm antimony, fully compliant with EU Directive 2015/863/EU (RoHS 3). Lead content is below 1000 ppm, satisfying all RoHS restrictions without exemptions.