Nexperia USA Inc. BC846B/SNVL

Overview

BC846B/SNVL from Nexperia is an NPN general-purpose transistor in SOT23 (TO-236AB) package, rated for 65 V V_CEO, 100 mA I_C, and h_FE = 200–450 at V_CE = 5 V, I_C = 2 mA. It serves as a low-voltage switching and small-signal amplification device in consumer power management, LED driver bias networks, and microcontroller GPIO interface stages.

For engineers reviewing the BC846B/SNVL datasheet, BC846B/SNVL pinout, BC846B/SNVL application, or BC846B/SNVL equivalent, this page delivers verified electrical parameters, thermal behavior under FR4 PCB mounting, gain group B selection rationale, and validated alternatives for discrete BJT replacement in cost-sensitive SMT designs.

Technical Context

The BC846B/SNVL operates as a silicon planar epitaxial NPN transistor with base-emitter junction optimized for stable DC current gain across –55 °C to +150 °C ambient. Its h_FE binning (Group B) ensures predictable switching thresholds in digital logic level translation and provides consistent saturation voltage (V_CE(sat) ≤ 400 mV at I_C = 100 mA, I_B = 5 mA).

Thermal resistance R_th(j-a) is 500 K/W when mounted on standard FR4 with single-sided 35 µm copper, defining its safe continuous power dissipation limit of 250 mW at T_amb ≤ 25 °C. Breakdown ratings-V_(BR)CEO = 65 V, V_(BR)CBO = 80 V, V_(BR)EBO = 6 V-support robust operation in 5–24 V rail applications with transient margin.

Key Specifications

Pinout & Package

SOT23 (TO-236AB) plastic surface-mount package: 3-pin, 1.3 mm × 2.9 mm footprint, 1.1 mm height, tin-plated leads compatible with standard reflow profiles (J-STD-020). Thermal pad not present; thermal path relies on leadframe conduction through PCB copper.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC846B/SNVL, BC847B/SNVL trades 20 V breakdown margin for +60 mW power handling, while MMBT3904LT1G offers lower cost but sacrifices both voltage headroom and h_FE consistency-making BC846B/SNVL optimal for 24–48 V industrial control nodes needing predictable gain and robust transients.

Availability

BC846B/SNVL is available at Aetrix Electronics and suitable for LED driver bias stages, microcontroller GPIO interface circuits, and small-signal amplifier designs requiring stable component supply and consistent gain binning across production batches.

Supply support for BC846B/SNVL 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 and industrial-grade components.

The BC846x series targets cost-sensitive, space-constrained applications requiring proven reliability in consumer, industrial, and computing equipment-designed specifically for SMT scalability and long-term manufacturability in high-mix assembly lines.

FAQ

What is the maximum allowable base current for continuous operation?

The absolute maximum peak base current is 200 mA for single pulses ≤1 ms, but continuous operation must limit I_B to ensure junction temperature remains ≤150 °C. At I_C = 100 mA and h_FE = 200, I_B = 0.5 mA is sufficient for saturation; sustained I_B > 5 mA risks exceeding P_tot = 250 mW unless board-level thermal relief is added.

Can BC846B/SNVL replace BC846A in existing designs?

Yes, BC846B/SNVL can directly replace BC846A in most cases because both share identical package, pinout, and voltage/current ratings. However, BC846B has higher minimum h_FE (200 vs. 110), which may reduce required base drive but could increase sensitivity to base resistor tolerance-verify saturation margin at worst-case h_FE and temperature.

Is BC846B/SNVL qualified for automotive applications?

No. Per Nexperia's revision history (Rev. 12, July 2022), the BC846x series is explicitly marked "non-automotive qualified" and lacks AEC-Q101 testing. For automotive use, select the BC846B-Q series (e.g., BC846BQ), which undergoes extended temperature cycling, HTOL, and ESD validation per automotive standards.

How does thermal performance change on 2-layer versus 4-layer PCBs?

R_th(j-a) = 500 K/W is specified for single-sided FR4 (1 layer, 35 µm Cu). On 2-layer boards with internal ground plane, R_th(j-a) improves to ~350 K/W; on 4-layer boards with thermal vias to inner planes, it reaches ~220 K/W. This allows P_tot scaling to ~360 mW (2-layer) or ~570 mW (4-layer) at T_amb = 25 °C-verified via Nexperia's thermal simulation models.