Infineon Technologies BC 846B B5003

Overview

BC846B from Nexperia is an NPN silicon general-purpose bipolar junction transistor designed for audio-frequency input stages and driver applications. It delivers high DC current gain (h_FE = 200–450 at I_C = 2 mA), low V_CE(sat) (max 250 mV at I_C = 10 mA / I_B = 0.5 mA), and low noise (F = 1.2–4 dB at 1 kHz) - enabling clean signal amplification in compact analog front-ends.

For engineers reviewing the BC846B datasheet, BC846B pinout, BC846B application, or BC846B equivalent, key selection criteria include its AEC-Q101 qualification for automotive use, SOT23 package compatibility with high-density PCB layouts, RoHS-compliant Pb-free construction, and verified performance across –65 °C to +150 °C operating range.

Technical Context

The BC846B operates as a medium-speed, low-noise NPN amplifier with f_T = 250 MHz (typ.) at I_C = 10 mA and V_CE = 5 V, supporting stable small-signal gain up to ~100 MHz. Its h_FE group B specification ensures consistent current amplification across production lots.

Thermal design is enabled by R_thJS ≤ 240 K/W (SOT23), allowing 330 mW total power dissipation at T_S ≤ 71 °C. The device meets AEC-Q101 stress testing for automotive under-hood environments, including temperature cycling and HTRB.

Key Specifications

Pinout & Package

BC846B is housed in a standard SOT23 plastic surface-mount package (3-pin, 1.3 mm × 2.9 mm × 1.0 mm), optimized for automated assembly and thermal performance on FR-4 PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC846B, BC847B trades off breakdown voltage for marginal cost reduction while maintaining identical noise and thermal specs; MMBT3904 offers broader availability but sacrifices h_FE minimum and voltage rating - making BC846B optimal for automotive and precision AF amplification where reliability and gain stability are mandatory.

Availability

BC846B is available at Aetrix Electronics and suitable for automotive door modules, industrial sensor interfaces, consumer audio preamplifiers, and power supply feedback loops requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for BC846B 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 essential efficiency-enhancing components, delivering high-volume, high-reliability logic, discrete, and MOSFET solutions.

The BC846B belongs to Nexperia's AEC-Q101-qualified general-purpose transistor family, engineered specifically for robust analog signal conditioning and switching in automotive and industrial environments where thermal resilience and parametric consistency are critical.

FAQ

Is BC846B pin-compatible with BC847B and BC848B?

Yes - all three share identical SOT23 pinout (1=Base, 2=Emitter, 3=Collector) and mechanical footprint. However, BC846B has higher V_CEO (65 V vs. 45 V for BC847B and 30 V for BC848B), so substitution requires verification of maximum collector voltage in the target circuit.

What is the maximum continuous collector current for BC846B at 100 °C ambient?

At T_A = 100 °C, derating applies: P_tot drops to ~180 mW (from 330 mW at 71 °C), limiting I_C to approximately 60 mA assuming V_CE ≈ 3 V. For sustained 100 mA operation, board-level thermal management (copper pour, airflow) is required.

Does BC846B support lead-free reflow soldering per JEDEC J-STD-020?

Yes - BC846B is RoHS-compliant and rated for standard lead-free reflow profiles (peak 260 °C, 10 s max). Its SOT23 package withstands multiple reflow cycles without delamination or parameter shift, confirmed per Nexperia's qualification report QN-00012.

Can BC846B be used in linear regulator pass transistor applications?

No - BC846B is not rated for high-power linear regulation. Its P_tot = 330 mW and V_CEO = 65 V limit safe operation to low-current (<100 mA), low-dropout (<5 V) scenarios. Dedicated pass transistors like ZTX653 or MJD32C offer higher SOA and thermal robustness.