Nexperia USA Inc. BCX71K,215

Overview

BCX71K,215 from Nexperia is a PNP general-purpose bipolar junction transistor in SOT23 package, rated for −45 V V_CEO, −100 mA I_C, and featuring h_FE = 380–630 at I_C = −2 mA, used in low-noise amplification and switching within hybrid analog circuits.

For engineers reviewing the BCX71K,215 datasheet, BCX71K,215 pinout, BCX71K,215 application, or BCX71K,215 equivalent, this device is selected for low-frequency signal conditioning, emitter-follower buffering, and discrete logic-level translation where low base drive and stable DC gain are required.

Technical Context

This PNP transistor operates with open-base V_CEO = −45 V and open-emitter V_CBO = −45 V, supporting reliable cutoff and saturation in low-voltage bias networks. Its f_T = 100 MHz enables usable gain up to audio and low-RF frequencies.

Low noise figure (2–6 dB at 1 kHz) and tight h_FE distribution (380–630 at −2 mA) make it suitable for preamplifier stages where signal integrity and predictable current sourcing matter. C_c = 4.5 pF and C_e = 11 pF define its small-signal capacitance profile under standard bias conditions.

Key Specifications

Pinout & Package

BCX71K,215 is housed in a plastic surface-mount SOT23 (TO-236AB) package, measuring 2.9 × 1.3 × 1.0 mm, optimized for automated assembly and thermal dissipation on FR4 PCBs (R_th(j-a) = 500 K/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BCX71K,215, BC857BK,215 offers equivalent performance with updated documentation lineage, while MMBT3906LT1G trades gain consistency and voltage margin for broader distributor availability-making BCX71K,215 optimal for noise-sensitive, rail-tolerant designs requiring predictable h_FE.

Availability

BCX71K,215 is available at Aetrix Electronics and suitable for audio pre-amplification, level translation, and low-power switching requiring stable component supply, consistent parametric binning, and long-term industrial lifecycle support.

Supply support for BCX71K,215 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 leader in discrete, logic, and PowerMOS semiconductors, formed in 2017 from the former NXP Standard Products division, with focus on automotive, industrial, computing, and consumer markets.

The BCX71K,215 belongs to Nexperia's BCX71 series of PNP general-purpose transistors, designed specifically for low-noise, low-frequency amplification and robust switching in space-constrained hybrid circuits.

FAQ

What is the maximum continuous collector current for BCX71K,215?

The BCX71K,215 has a maximum DC collector current rating of −100 mA at T_amb ≤ 25 °C. Derating applies above this temperature per the R_th(j-a) = 500 K/W thermal resistance; at 70 °C ambient, usable I_C drops to approximately −65 mA to maintain T_j ≤ 150 °C.

Is BCX71K,215 pin-compatible with NPN complements like BCX70 series?

Yes-BCX71K,215 shares the same SOT23 pinout (1=Base, 2=Emitter, 3=Collector) as BCX70 series NPN transistors, enabling direct complementary pair implementation in push-pull or differential stages without layout changes.

Does BCX71K,215 support operation at elevated temperatures?

Yes-its specified storage and operating ambient temperature range is −65 °C to +150 °C, and maximum junction temperature is 150 °C. Reliable operation up to 125 °C ambient is achievable with appropriate PCB copper area and airflow, given its 500 K/W junction-to-ambient thermal resistance.

How does the noise performance of BCX71K,215 compare to other SOT23 PNP transistors?

BCX71K,215 achieves a noise figure of 2–6 dB at 1 kHz with 2 kΩ source resistance-among the lowest in its class. This outperforms standard PNP transistors like MMBT3906 (typically 10–12 dB), making it preferred for microphone preamps and sensor signal conditioning where noise floor matters.