Infineon Technologies BC 846A E6433

Overview

BC846A E6433 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 = 110–220 at I_C = 10 µA–2 mA), low V_CE(sat) (≤250 mV at I_C = 10 mA/I_B = 0.5 mA), and low noise (F = 1.2–4 dB, V_n ≤ 0.135 µV) in the 30 Hz–15 kHz band, supporting high-fidelity signal amplification in compact consumer audio circuits.

For engineers reviewing the BC846A E6433 datasheet, BC846A E6433 pinout, BC846A E6433 application, or BC846A E6433 equivalent, key selection criteria include its AEC-Q101 qualification, SOT23 package thermal resistance (R_thJS ≤ 240 K/W), RoHS-compliant Pb-free construction, and verified performance across automotive infotainment preamp and industrial sensor interface designs.

Technical Context

The BC846A operates as a discrete NPN BJT with fixed emitter-base and collector-base junctions optimized for linear amplification and switching in low-power analog signal paths. Its h_FE grouping (A-grade) ensures consistent current amplification between 110–220 across I_C = 10 µA to 2 mA, while its f_T of 250 MHz supports stable operation up to mid-VHF frequencies without parasitic oscillation.

Thermal design relies on its SOT23 package's defined R_thJS ≤ 240 K/W and P_tot = 330 mW at T_S ≤ 71 °C, enabling reliable operation in thermally constrained PCB layouts. The device meets AEC-Q101 stress testing for automotive under-hood environments, including temperature cycling and humidity bias.

Key Specifications

Pinout & Package

BC846A E6433 is housed in a standard SOT23 plastic surface-mount package (3-pin, 1.3 mm × 2.9 mm × 1.0 mm), with lead-free terminations and JEDEC-compliant footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN general-purpose transistor applications.

Compared with BC846B E6433 and MMBT3904LT1G, BC846A E6433 provides optimal trade-off between gain consistency, breakdown safety margin, and low-noise performance-making it preferred for AEC-Q101-compliant audio and sensor front-ends requiring predictable h_FE and minimal thermal derating.

Availability

BC846A E6433 is available at Aetrix Electronics and suitable for automotive infotainment preamplifiers, industrial sensor signal conditioning, and portable medical monitor front-ends requiring stable component supply across extended product lifecycles.

Supply support for BC846A E6433 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 solutions.

The BC846A belongs to Nexperia's BC846–BC850 family of general-purpose NPN transistors engineered specifically for audio-frequency amplification, switching, and driver functions in space-constrained, thermally demanding environments.

FAQ

Is BC846A E6433 pin-compatible with BC847A or BC848A?

Yes-BC846A, BC847A, and BC848A share identical SOT23 pinout (1=Base, 2=Emitter, 3=Collector) and mechanical footprint. However, they differ in maximum ratings: BC846A supports 65 V V_CEO, BC847A is rated for 45 V, and BC848A for 30 V. Substitution requires verification of voltage headroom in the target circuit.

What is the maximum continuous collector current for BC846A E6433?

The absolute maximum continuous collector current (I_C) is 100 mA at T_A = 25 °C. Derating applies above 71 °C case temperature, where total power dissipation drops from 330 mW to zero at 150 °C junction temperature, per the specified R_thJS ≤ 240 K/W thermal path.

Does BC846A E6433 support pulsed operation beyond its DC ratings?

Yes-pulse operation up to 200 mA peak collector current (I_CM) is permitted for pulse widths ≤ 10 ms with duty cycle ≤ 2%, as defined in the Absolute Maximum Ratings table. This enables short-duration drive pulses for relay or buzzer control without thermal runaway.

How does BC846A E6433 perform in low-noise audio applications compared to BC849A?

BC846A specifies noise figure F = 1.2–4 dB at 1 kHz, while BC849A (higher h_FE grade) achieves lower F = 1.2 dB typical. However, BC846A maintains superior V_CEO (65 V vs. 30 V) and lower C_cb (0.95 pF), making it more suitable for wide-dynamic-range, high-voltage audio inputs where noise and breakdown margin are both critical.