onsemi BC212L_J35Z

Overview

BC212L_J35Z from Fairchild Semiconductor is a PNP general-purpose bipolar junction transistor (BJT) designed for low-to-medium power linear amplification and switching, with DC current gain (hFE) of 300 at IC = 10 µA, VCE = 5 V; VCEO = 50 V; IC(max) = 300 mA; TO-92 package; used in audio preamplifier stages and discrete logic interface circuits.

For engineers reviewing the BC212L_J35Z datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed hFE range, VCE(sat) ≤ 0.6 V at IC = 100 mA/IB = 5 mA, fT = 200 MHz, thermal resistance RθJA = 200°C/W, and TO-92 mechanical compatibility in space-constrained analog signal paths.

Technical Context

The BC212L_J35Z operates as a silicon PNP BJT fabricated on Fairchild's Process 68, optimized for stable DC amplification and moderate-frequency small-signal performance. Its hfe = 60 at IC = 2 mA enables predictable biasing in Class-A amplifier configurations, while fT = 200 MHz supports bandwidth-critical applications up to ~20 MHz with proper layout.

Thermal design is constrained by RθJA = 200°C/W and PD = 625 mW at 25°C, requiring derating above ambient - 5.0 mW/°C - and limiting continuous operation at full IC without heatsinking. VBE(sat) = 1.1 V and VCE(sat) = 0.6 V at IC = 100 mA/IB = 5 mA define its switching efficiency envelope.

Key Specifications

Pinout & Package

BC212L_J35Z is housed in a standard TO-92 plastic package with 3 leads: Emitter (E), Base (B), Collector (C). Lead identification follows JEDEC TO-92 outline: flat side facing viewer, leads down, left-to-right = E-B-C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC557 and MPSA92, BC212L_J35Z offers superior low-current gain consistency and higher fT within its 50 V rating, making it optimal for compact, noise-sensitive amplification where thermal limits permit TO-92 operation.

Availability

BC212L_J35Z is available at Aetrix Electronics and suitable for audio preamplifier stages, discrete logic level shifters, and LED indicator drivers requiring stable component supply across prototyping, pilot production, and long-lifecycle industrial deployments.

Supply support for BC212L_J35Z 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

Fairchild Semiconductor was a U.S.-based designer and manufacturer of analog and discrete semiconductors, acquired by ON Semiconductor in 2016; known for robust process technologies and broad portfolio of BJTs, MOSFETs, and optoelectronics.

The BC212L_J35Z belongs to Fairchild's general-purpose PNP BJT family developed for cost-sensitive, medium-performance analog signal conditioning and discrete switching in consumer, industrial, and automotive auxiliary systems.

FAQ

What is the maximum collector-emitter voltage rating for BC212L_J35Z?

The BC212L_J35Z has a maximum collector-emitter breakdown voltage (BVCEO) of 50 V under test condition IC = 2 mA. This rating defines the highest DC voltage that can be safely applied between collector and emitter with the base open. Exceeding this value risks irreversible device failure. Designers should maintain at least 20% derating margin in safety-critical applications.

Does BC212L_J35Z have a specified noise figure, and under what conditions?

Yes, BC212L_J35Z has a noise figure (NF) of 10 dB, measured at IC = 200 µA, VCE = 5 V, f = 1 kHz, Rg = 2 kΩ, and BW = 200 Hz. This value is relevant for low-level signal amplification tasks such as microphone preamplifiers, where preserving signal-to-noise ratio is essential. It is not characterized at RF frequencies or higher collector currents.

What is the thermal resistance of BC212L_J35Z, and how does it affect PCB layout?

The BC212L_J35Z has a junction-to-ambient thermal resistance (RθJA) of 200°C/W in free-air TO-92 mounting. This means each watt of dissipated power raises the junction temperature by 200°C above ambient. To sustain 300 mW continuously, PCB copper pour or airflow is recommended. Layout must avoid enclosing the TO-92 body and ensure ≥25 mm² of 1-oz copper connected to the emitter pad.

Is BC212L_J35Z suitable for switching applications, and what is its saturation voltage?

Yes, BC212L_J35Z is suitable for discrete switching due to its specified VCE(sat) = 0.6 V at IC = 100 mA and IB = 5 mA. This low saturation voltage minimizes power loss during conduction. For reliable switching, base drive must deliver ≥5 mA, and turn-off should include a base-emitter resistor to prevent storage time delay. It is not rated for high-frequency PWM above 100 kHz.

How does the DC current gain (hFE) of BC212L_J35Z vary with operating conditions?

The BC212L_J35Z exhibits hFE = 300 minimum at IC = 10 µA and VCE = 5 V, and hFE = 60 at IC = 2 mA and VCE = 5 V. Gain decreases at higher currents and is temperature-sensitive - typically increasing ~0.5%/°C. Designers should use the 300-value for low-current bias networks and the 60-value for medium-current switching analysis to ensure worst-case margin.