Nexperia USA Inc. BCX51,115

Overview

BCX51,115 from Nexperia is a PNP medium-power surface-mount transistor in SOT89 (SC-62/TO-243) package, rated for −45 V V_CEO, −1 A continuous collector current, and 0.50 W power dissipation on standard FR4 PCB. It features three h_FE gain selections (63–160 or 100–250), AEC-Q101 qualification, and an exposed collector pad for enhanced thermal and electrical conductivity. It is used in high-side switches and linear voltage regulators in automotive and industrial power management.

For engineers reviewing the BCX51,115 datasheet, BCX51,115 pinout, BCX51,115 application, or BCX51,115 equivalent, this page delivers verified specifications, validated SOT89 pin mapping, real-world use cases in battery-driven devices and MOSFET drivers, and two confirmed alternative parts with documented technical and application differences.

Technical Context

The BCX51,115 operates as a PNP bipolar junction transistor optimized for medium-power linear and switching applications. Its design centers on robust thermal performance via an exposed collector pad and supports DC current gain selection (h_FE = 63–160 or 100–250 at V_CE = −2 V, I_C = −150 mA), enabling precise biasing in regulator feedback paths and driver stages.

It meets AEC-Q101 stress qualification for automotive environments and exhibits low V_CE(sat) (≤ −0.5 V at I_C = −500 mA, I_B = −50 mA) and moderate f_T (145 MHz), confirming suitability for stable low-to-moderate frequency power control-not RF or high-speed digital switching.

Key Specifications

Pinout & Package

SOT89 (SC-62/TO-243) plastic surface-mounted package with 3 leads and an exposed collector pad for thermal and electrical conduction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP medium-power transistor applications.

Compared with BCP54,115, BCX51,115 enables direct high-side implementation without level-shifting; versus BC51PA,115, it trades 0.2 mm² footprint reduction for easier manual rework and wider distributor availability in SOT89 tape-and-reel formats.

Availability

BCX51,115 is available at Aetrix Electronics and suitable for linear voltage regulators, high-side switches, battery-driven devices, and MOSFET drivers requiring stable component supply across automotive, industrial, and medical electronics programs.

Supply support for BCX51,115 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 essential efficiency technologies, delivering high-performance, reliable discrete and logic components for automotive, industrial, and consumer markets.

The BCX51,115 belongs to Nexperia's AEC-Q101-qualified PNP medium-power transistor family, engineered for robust thermal performance and precise gain control in automotive power management and industrial control systems.

FAQ

What is the maximum allowable base current for BCX51,115?

The absolute maximum DC base current is −0.3 A, and peak pulsed base current is also limited to −0.3 A for tp ≤ 1 ms. Exceeding this risks permanent degradation of h_FE or bond wire failure. For typical switching operation at I_C = −500 mA, a base drive of −50 mA (I_C/I_B = 10) is recommended to ensure saturation while staying within safe operating area limits.

Is BCX51,115 suitable for use in automotive engine control units?

Yes-BCX51,115 is AEC-Q101 qualified and specified for operation from −55 °C to +150 °C junction temperature. Its −45 V V_CEO, −1 A I_C, and robust transient thermal impedance (Z_th(j-a)) make it appropriate for non-safety-critical engine bay functions such as sensor biasing, fuel pump pre-regulation, and auxiliary load switching, provided layout adheres to Nexperia's SOT89 thermal footprint guidelines.

How does the SOT89 package improve thermal performance over standard SOT23?

The SOT89 package features an exposed collector pad that serves as both electrical connection and primary thermal path to the PCB. With R_th(j-sp) = 16 K/W and R_th(j-a) = 250 K/W on standard FR4, it achieves ~35% lower junction temperature than comparable SOT23 devices at 500 mA. This allows sustained operation near I_C = −1 A with only 1 cm² of copper, whereas SOT23 would require derating to ≤ −300 mA.

What do the marking codes 'AC' and 'AD' indicate on BCX51,115 devices?

'AC' denotes h_FE = 63–160 at V_CE = −2 V and I_C = −150 mA; 'AD' indicates h_FE = 100–250 under identical conditions. These factory-binned gain ranges are laser-marked for traceability and allow designers to select consistent DC current gain without post-production testing-critical for production-line calibration of linear regulators and precision amplifiers.