Nexperia USA Inc. BC856AQCZ

Overview

BC856AQC from Nexperia is a PNP general-purpose transistor in a DFN1412D-3 (SOT8009) leadless package, rated for −65 V V_CEO, −100 mA I_C, and 360 mW P_tot at T_amb ≤ 25 °C. It delivers h_FE = 125–250 at V_CE = −5 V and I_C = −2 mA, with side-wettable flanks for AOI-compatible solder joint inspection, and is used in low-power switching and amplification circuits on space-constrained PCBs.

For engineers reviewing the BC856AQC datasheet, BC856AQC pinout, BC856AQC application, or BC856AQC equivalent, this page provides verified package dimensions, thermal derating curves, saturation voltage behavior across temperature, base-emitter voltage vs. collector current, and validated alternatives for PNP small-signal replacement in consumer and industrial control designs.

Technical Context

This transistor operates as a discrete PNP bipolar junction device optimized for linear amplification and digital switching in low-voltage, low-current signal paths. Its DFN1412D-3 package enables high-density placement and automated optical inspection due to side-wettable flanks and 0.5 mm profile.

It exhibits V_BE(sat) ≤ −850 mV at I_C = −100 mA / I_B = −5 mA, V_CE(sat) ≤ −650 mV under same conditions, and f_T = 100 MHz at V_CE = −5 V / I_C = −10 mA - confirming suitability for audio-frequency amplification and fast-switching logic interface stages.

Key Specifications

Pinout & Package

BC856AQC uses the DFN1412D-3 (SOT8009) ultra-small leadless package: 1.4 mm × 1.2 mm × 0.48 mm body, 0.8 mm pitch, side-wettable flanks, and 0.5 mm max height - enabling AOI compatibility and high board density.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC856BQC, BC856AQC offers lower h_FE spread for predictable base drive in digital switching, while MMBT3906DW trades voltage headroom and thermal margin for dual-device integration - making BC856AQC optimal for cost-sensitive, space-constrained −65 V PNP switching where gain consistency matters.

Availability

BC856AQC is available at Aetrix Electronics and suitable for LED driver circuits, level-shifting interfaces, low-power sensor biasing, and power rail sequencing requiring stable component supply and AOI-compatible manufacturing.

Supply support for BC856AQC 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-grade and industrial-standard components.

The BC856xQC series targets space-constrained, cost-sensitive applications needing robust PNP switching and amplification - emphasizing manufacturability (side-wettable flanks), thermal predictability, and consistent DC gain across temperature.

FAQ

What is the maximum allowable junction temperature for BC856AQC?

The absolute maximum junction temperature (T_j) is 150 °C per IEC 60134 limiting values. Operation above this threshold risks permanent degradation of h_FE and increased leakage. Thermal design must ensure T_j remains below 150 °C under worst-case ambient and power dissipation, using R_th(j-a) = 348 K/W for FR4 with 35 µm copper.

Can BC856AQC replace BC856BQC in existing designs?

Yes, BC856AQC is pin- and package-compatible with BC856BQC, but its lower h_FE range (125–250 vs. 220–475) may require verification of base drive sufficiency. If the original design uses minimal base current or relies on high gain for margin, recalculation of R_B is recommended to ensure saturation under all operating conditions.

Does BC856AQC support reflow soldering with standard lead-free profiles?

Yes - Nexperia specifies compatibility with JEDEC J-STD-020D.2 lead-free reflow profiles. The DFN1412D-3 package has been qualified for peak temperatures up to 260 °C, and footprint recommendations (Fig. 13) include 0.1 mm stencil thickness and defined land patterns to ensure reliable solder joint formation and AOI visibility.

How does thermal performance differ between 35 µm and 70 µm copper PCBs?

R_th(j-a) improves from 348 K/W to 278 K/W when upgrading from 35 µm to 70 µm copper on FR4, enabling ~19% higher continuous power dissipation at the same ambient temperature. This difference is critical in sealed enclosures or high-temperature environments where passive cooling is limited and thermal margin must be maximized.