onsemi BC559_J35Z

Overview

BC559_J35Z from onsemi is a PNP epitaxial silicon transistor optimized for low-noise amplification and general-purpose switching in analog signal paths, with V_CEO = −30 V, I_C = −100 mA, h_FE = 420–800 (Class C), f_T = 150 MHz, and V_BE(on) = −600 to −750 mV at I_C = −2 mA - used in audio preamplifiers, sensor interface stages, and discrete logic inverters.

For engineers reviewing the BC559_J35Z datasheet, pinout, applications, or equivalent options, key selection criteria include its low-noise figure (1.2–4.0 dB at 30–15 kHz), TO-92-3 package compatibility, Class C h_FE binning, and complementary pairing with BC549/BC550 NPN devices in push-pull configurations.

Technical Context

The BC559_J35Z operates as a medium-power, low-noise PNP bipolar junction transistor with fixed-emitter biasing capability and DC current gain controlled by base current injection. Its design supports linear amplification up to 150 MHz and switching with V_CE(sat) ≤ −650 mV at I_C = −100 mA / I_B = −5 mA.

It shares the BC556–BC560 family architecture but is specifically binned for Class C h_FE (420–800) and optimized for noise-sensitive small-signal applications - distinct from BC556 (high-voltage) and BC557/BC558 (mid-range gain/noise). Junction temperature rating is 150°C with 500 mW total dissipation at 25°C.

Key Specifications

Pinout & Package

BC559_J35Z is housed in a TO-92-3 plastic package (Case 135AR), lead-formed, with standard pinout: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BC559C and BC558B, BC559_J35Z delivers the highest guaranteed h_FE and lowest noise floor in the BC55x series, making it optimal for precision analog signal chains where gain consistency and SNR are critical - while maintaining full TO-92 footprint compatibility.

Availability

BC559_J35Z is available at Aetrix Electronics and suitable for audio preamplifiers, sensor interface circuits, and discrete logic inverters requiring stable component supply and long-term industrial availability.

Supply support for BC559_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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and IoT applications.

The BC559_J35Z belongs to onsemi's legacy BC5xx PNP/NPN transistor family, designed for cost-effective, reliable discrete amplification and switching in consumer, industrial, and instrumentation equipment.

FAQ

What is the h_FE range for BC559_J35Z?

The BC559_J35Z is binned to Class C h_FE, with a guaranteed DC current gain range of 420 to 800 at V_CE = −5 V and I_C = −2 mA. This high-gain bin reduces base drive requirements and improves linearity in low-noise amplifier designs using the BC559_J35Z.

Is BC559_J35Z RoHS compliant and lead-free?

Yes, BC559_J35Z is RoHS compliant and manufactured as Pb-free, halogen-free, and BFR-free per onsemi's specifications. It meets EU Directive 2011/65/EU and is qualified for lead-free reflow soldering processes - confirmed in the official BC556–BC560 datasheet revision 3 (June 2024).

What is the maximum operating temperature for BC559_J35Z?

The BC559_J35Z has a maximum junction temperature (T_J) of 150°C and a storage temperature range of −65°C to +150°C. Its thermal resistance R_JA is 250°C/W, requiring appropriate PCB copper area and derating (4.0 mW/°C above 25°C ambient) to maintain reliability in continuous operation.

Does BC559_J35Z have a specified noise figure?

Yes, BC559_J35Z has a noise figure (NF) of 1.2–4.0 dB measured at V_CE = −5 V, I_C = −200 µA, R_G = 2 kΩ, and frequency range 30–15,000 Hz - confirming its suitability for low-noise audio and sensor signal amplification applications using the BC559_J35Z.

What package type does BC559_J35Z use?

BC559_J35Z uses the TO-92-3 plastic package (Case 135AR), lead-formed, with standard pinout: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter. Dimensions are 4.83 mm × 4.76 mm, compatible with automated through-hole assembly and manual prototyping.