Nexperia USA Inc. BC856BQC-QZ

Overview

BC856BQC-QZ from Nexperia is a PNP general-purpose transistor in a DFN1412D-3 (SOT8009) leadless SMD package with side-wettable flanks, rated for −65 V V_CEO, −100 mA I_C, and DC current gain (h_FE) of 220–475 at V_CE = −5 V and I_C = −2 mA. It supports automotive-grade reliability per AEC-Q101 and delivers low saturation voltage (V_CEsat ≤ −650 mV at I_C = −100 mA, I_B = −5 mA), enabling compact switching in space-constrained PCBs.

For engineers reviewing the BC856BQC-QZ datasheet, BC856BQC-QZ pinout, BC856BQC-QZ application, or BC856BQC-QZ equivalent, this device is selected for high-density PNP switching where thermal performance (R_th(j-a) = 278 K/W on 70 µm FR4), AOI-compatible solder joints, and −55 °C to +150 °C ambient operation are critical.

Technical Context

This PNP bipolar junction transistor operates in active, saturation, and cutoff regions with defined breakdown limits: −80 V V_CBO, −65 V V_CEO, and −6 V V_EBO. Its h_FE range (220–475) ensures predictable current amplification across production lots under standard bias conditions (V_CE = −5 V, I_C = −2 mA).

Thermal derating follows two curves: 360 mW at T_amb ≤ 25 °C on 35 µm copper PCB, scaling to 450 mW on 70 µm copper PCB. Transient thermal impedance data confirms suitability for pulsed loads up to 200 mA (t_p ≤ 1 ms) without junction overheating.

Key Specifications

Pinout & Package

DFN1412D-3 (SOT8009) is a 3-terminal, leadless plastic package with 0.8 mm pitch, 0.5 mm height, and side-wettable flanks for automated optical inspection of solder joints. Dimensions: 1.4 mm × 1.2 mm × 0.48 mm body, with exposed thermal pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC856BQC-QZ, the BC856B,115 offers identical electrical behavior but inferior thermal and manufacturability specs, while MMBT3906LT1G trades AEC-Q101 compliance and high-current saturation assurance for broader distributor availability at lower unit cost.

Availability

BC856BQC-QZ is available at Aetrix Electronics and suitable for automotive electronics, portable medical devices, and industrial sensor nodes requiring stable component supply, AEC-Q101 compliance, and ultra-compact packaging.

Supply support for BC856BQC-QZ 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 specializing in high-performance, high-reliability discrete, logic, and MOSFET solutions, with leadership in automotive-qualified components and advanced packaging.

The BC856xQC-Q series belongs to Nexperia's AEC-Q101-qualified general-purpose transistor family, engineered for space-constrained automotive and industrial switching where AOI compatibility, thermal efficiency, and parametric consistency are essential.

FAQ

What is the marking code for BC856BQC-QZ?

The marking code for BC856BQC-QZ is '9U', laser-etched on the top surface of the DFN1412D-3 package. This 2-character code uniquely identifies the B-gain variant within the BC856xQC-Q series and is visible under 20× magnification for traceability and verification during assembly inspection.

Does BC856BQC-QZ require a thermal pad connection on the PCB?

No, the DFN1412D-3 package has an exposed thermal pad that is not electrically connected to any internal die structure. It may be left floating or grounded for mechanical stability, but it does not serve as a functional terminal and carries no electrical signal or power path.

Can BC856BQC-QZ replace BC856B in existing SOT23 designs?

No direct replacement is possible without PCB redesign. BC856BQC-QZ uses the DFN1412D-3 (SOT8009) footprint-1.4 mm × 1.2 mm with 0.8 mm pitch-whereas BC856B uses SOT23-2.9 mm × 1.3 mm with 1.9 mm pitch. Layout, stencil, and reflow profiles must be updated to accommodate the smaller, leadless package.

What is the maximum allowable peak collector current for BC856BQC-QZ?

The maximum peak collector current is −200 mA for single pulses with duration ≤ 1 ms and duty cycle ≤ 0.02. This rating assumes operation at T_amb = 25 °C on a standard FR4 PCB; sustained pulsing requires thermal validation using the Z_th(j-a) curves in Figures 2 and 3 of the datasheet.