Nexperia USA Inc. BC856BQBZ

Overview

BC856BQBZ from Nexperia is a PNP general-purpose transistor in a DFN1110D-3 (SOT8015) leadless SMD package, 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 serves as a compact, high-reliability switching and amplification device in space-constrained consumer and industrial PCBs.

For engineers reviewing the BC856BQBZ datasheet, BC856BQBZ pinout, BC856BQBZ application, or BC856BQBZ equivalent, this page delivers verified package dimensions, thermal derating curves, AOI-compatible side-wettable flank geometry, and validated alternatives for low-voltage PNP switching designs requiring <1 mm height and <1.1 mm × 1.0 mm footprint.

Technical Context

This transistor operates as a discrete PNP bipolar junction device with base-controlled current amplification. Its design emphasizes manufacturability on fine-pitch PCBs via side-wettable flanks and supports pulsed operation up to 200 mA I_CM with 150 °C maximum junction temperature.

Thermal performance is defined by two R_th(j-a) values: 368 K/W on 35 µm copper FR4 and 298 K/W on 70 µm copper FR4. Saturation behavior is characterized at I_C/I_B = 20, with V_CE(sat) ≤ −650 mV at I_C = −100 mA and I_B = −5 mA.

Key Specifications

Pinout & Package

DFN1110D-3 (SOT8015) is a 3-terminal, leadless, ultra-thin plastic package with side-wettable flanks, measuring 1.1 mm × 1.0 mm × 0.48 mm and featuring a 0.65 mm pin pitch. Its low 0.5 mm profile supports thin-profile portable electronics and stacked PCB assemblies.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC856B,115 and MMBT3906LT1G, BC856BQBZ delivers superior manufacturability in high-density designs via side-wettable flanks and 55% smaller footprint, while maintaining higher voltage margin and tighter h_FE consistency for predictable base drive sizing.

Availability

BC856BQBZ is available at Aetrix Electronics and suitable for LED driver circuits, level-shifting interfaces, sensor bias load switches, and audio preamplifier stages requiring stable component supply and consistent parametric performance across production lots.

Supply support for BC856BQBZ 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 essential semiconductors, with leadership in logic, discretes, and MOSFETs for automotive, industrial, and consumer markets.

The BC856xQB series belongs to Nexperia's ultra-miniature general-purpose transistor product line, engineered specifically for space-constrained, AOI-capable SMT applications demanding consistent h_FE, low saturation voltage, and robust thermal performance in sub-1 mm packages.

FAQ

Is BC856BQBZ pin-compatible with BC856B in SOT23?

No. BC856BQBZ uses DFN1110D-3 (SOT8015) with side-wettable flanks and a 1.1 mm × 1.0 mm footprint, while BC856B uses SOT23 (2.9 mm × 1.3 mm) with gull-wing leads. The pin numbering (1=B, 2=E, 3=C) matches electrically, but mechanical mounting, soldering, and PCB layout are incompatible without redesign.

What is the maximum allowable PCB copper thickness for full-rated P_tot?

The 420 mW total power dissipation rating assumes a single-sided FR4 PCB with 70 µm (2 oz) copper and standard footprint. Using thinner copper (e.g., 35 µm / 1 oz) reduces P_tot to 340 mW. Thermal performance degrades further with internal layers or non-standard land patterns.

Can BC856BQBZ replace BC857B in a circuit?

No. BC857B is a −45 V V_CEO, −100 mA PNP with different h_FE binning (120–240) and SOT323 package. Substituting BC856BQBZ introduces −65 V over-rating but risks gain mismatch and thermal stress due to differing R_th(j-a) and package thermal mass-validation is required.

Does BC856BQBZ support reflow soldering per JEDEC J-STD-020?

Yes. The DFN1110D-3 package is qualified for standard lead-free reflow profiles (peak 260 °C, 20–40 s above 217 °C). Nexperia specifies a recommended stencil thickness of 0.1 mm and provides exact solder paste land patterns in Figure 13 of the datasheet for optimal wetting and void control.