onsemi BC307B_J35Z

Overview

BC307B_J35Z from Fairchild Semiconductor is a PNP epitaxial silicon transistor optimized for low-noise amplifier and switching applications, with h_FE 180–460, V_CEO = −45 V, I_C = −100 mA, P_C = 500 mW, and TO-92 package. It delivers stable DC gain at −5 V V_CE and −2 mA I_C, supporting audio preamplifier stages and relay drivers in industrial control systems.

For engineers reviewing the BC307B_J35Z datasheet, pinout, applications, or equivalent options, key selection considerations include its verified h_FE classification B (180–460), guaranteed V_CEO rating, TO-92 mechanical compatibility, low saturation voltage (−0.5 V at −10 mA/−0.5 mA), and noise figure of 2 dB at 1 kHz.

Technical Context

This PNP bipolar junction transistor operates with emitter-grounded configuration and supports linear amplification and saturated switching modes. Its h_FE range (180–460) and f_T of 130 MHz enable mid-frequency analog signal conditioning up to ~10 MHz, while V_BE(sat) ≤ −0.7 V ensures efficient base drive in low-voltage logic interfaces.

Thermal design is enabled by a 150°C maximum junction temperature and 500 mW power dissipation rating in the TO-92 package. The device exhibits Cob = 6 pF and Cib = 12 pF at 1 MHz, supporting predictable high-frequency stability in discrete gain blocks without external compensation.

Key Specifications

Pinout & Package

BC307B_J35Z is housed in a standard TO-92 plastic package with 3 leads, lead spacing 1.27 mm, body height 3.86 mm max, and overall length 4.58 mm. Pin 1 is Collector, Pin 2 is Base, Pin 3 is Emitter - confirmed per Fairchild Rev. A2 datasheet Figure "Package Dimensions" and "1. Collector 2. Base 3. Emitter" annotation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC557B and PN2907A, BC307B_J35Z offers superior high-frequency response (130 MHz f_T) and documented 2 dB noise figure-making it preferred for audio and precision analog circuits where both bandwidth and SNR matter, while retaining full TO-92 mechanical compatibility.

Availability

BC307B_J35Z is available at Aetrix Electronics and suitable for audio preamplifier stages, relay driver circuits, and DC power supply error amplifiers requiring stable component supply, long-term obsolescence management, and traceable sourcing.

Supply support for BC307B_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 semiconductor company specializing in power management, analog, and discrete components before its acquisition by ON Semiconductor in 2016.

The BC307 series belongs to Fairchild's legacy general-purpose PNP transistor product line, designed specifically for cost-sensitive, high-reliability linear amplification and switching in industrial, consumer, and instrumentation equipment.

FAQ

What is the h_FE range for BC307B_J35Z?

The BC307B_J35Z has a confirmed DC current gain (h_FE) range of 180 to 460 at V_CE = −5 V and I_C = −2 mA, per Fairchild's Rev. A2 datasheet classification table. This B-grade binning ensures consistent gain behavior across production units, supporting reliable bias design in amplifier and switching circuits using the BC307B_J35Z.

Is BC307B_J35Z suitable for low-noise audio applications?

Yes - BC307B_J35Z is explicitly characterized with a noise figure of 2 dB at 1 kHz (V_CE = −5 V, I_C = −0.2 mA, R_G = 2 kΩ), making it appropriate for microphone preamplifiers and other low-level analog signal paths. This specification is measured and published in the official BC307/308/309 datasheet, confirming its suitability for noise-critical use of BC307B_J35Z.

What is the maximum collector-emitter voltage rating for BC307B_J35Z?

The BC307B_J35Z has a maximum collector-emitter voltage (V_CEO) rating of −45 V under open-base conditions at T_a = 25°C, as specified in the Absolute Maximum Ratings table of the Fairchild BC307/308/309 datasheet. This rating defines the upper limit for safe DC operation in negative-rail configurations using BC307B_J35Z.

Does BC307B_J35Z have a defined saturation voltage?

Yes - BC307B_J35Z specifies V_CE(sat) = −0.5 V typical at I_C = −10 mA and I_B = −0.5 mA, and −0.3 V at I_C = −100 mA and I_B = −5 mA. These values confirm its capability as a low-loss switch in relay drivers and digital logic interfaces using BC307B_J35Z in saturated mode.

What package type does BC307B_J35Z use?

BC307B_J35Z uses the standard TO-92 plastic package with three leads arranged as Collector (Pin 1), Base (Pin 2), and Emitter (Pin 3). Mechanical dimensions - including lead pitch (1.27 mm), body height (≤3.86 mm), and overall length (4.58 mm) - are fully documented in the Fairchild BC307/308/309 Rev. A2 datasheet Package Dimensions diagram for BC307B_J35Z.