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Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Single Bipolar Transistors

onsemi BC559B_J35Z

Name: BC559B_J35Z
Brand: onsemi
SKU: BC559B_J35Z
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BC559B_J35Z

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Datasheet:: BC559B_J35Z.pdf

Description:: TRANS PNP 30V 0.1A TO-92-3

Quantity:: RFQ Add To RFQ list

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Product details

Overview

BC559B_J35Z from onsemi is a PNP epitaxial silicon transistor optimized for low-noise amplification and general-purpose switching, with V_CEO = −30 V, h_FE = 200–450 (Class B), f_T = 150 MHz, and V_BE(on) = −600 to −750 mV at I_C = −2 mA - used in audio preamplifier stages and signal conditioning circuits where noise performance and DC gain stability are critical.

For engineers reviewing the BC559B_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, complementary pairing with BC549/BC550 NPN devices, and validated operation up to 150 °C junction temperature.

Technical Context

The BC559B_J35Z operates as a medium-gain, low-noise PNP bipolar junction transistor with fixed-emitter biasing capability and stable h_FE across −55 °C to +150 °C. Its f_T of 150 MHz supports audio-frequency amplification and moderate-speed switching up to ~10 MHz.

Designed for linear and saturated-mode operation, it features V_CE(sat) ≤ −300 mV at I_C = −10 mA/I_B = −0.5 mA and Cob = 6 pF at V_CB = −10 V, enabling predictable frequency response in RC-coupled amplifier topologies and low-distortion small-signal gain.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	−30 V - maximum collector-emitter voltage before breakdown; defines safe operating range in common-emitter amplifier configurations
h_FE (Class B)	200–450 - DC current gain at V_CE = −5 V, I_C = −2 mA; ensures consistent bias point stability in discrete gain stages
f_T	150 MHz - unity-gain bandwidth; supports high-fidelity audio amplification without phase shift degradation up to 20 kHz
Noise Figure	1.2–4.0 dB (30–15 kHz) - quantifies low-noise performance in microphone preamps and sensor front-ends
P_D	500 mW - total power dissipation at 25 °C; derates linearly at 4.0 mW/°C above ambient, limiting continuous I_C to ~100 mA
C_ob	6 pF - output capacitance at V_CB = −10 V; minimizes high-frequency roll-off in multi-stage amplifiers

Pinout & Package

BC559B_J35Z is housed in a TO-92-3 plastic package (Case 135AR), lead-formed, with standard pin configuration: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter.

Pin/Terminal	Circuit Role	Design Meaning
1 (Collector)	Current sink node	Connected to load or supply rail in common-emitter or common-base topologies; handles up to −100 mA DC
2 (Base)	Control input	Receives forward-biased current to drive transistor into active/saturation; requires −0.5 mA typical for 10 mA collector drive
3 (Emitter)	Current source node	Typically tied to ground or negative rail; provides reference for V_BE biasing and sets emitter degeneration resistance

Key Features

Feature	Design Value
Low-noise amplification	1.2–4.0 dB NF at audio frequencies enables clean signal amplification in microphone and sensor interfaces
Complementary pairing	Matched performance with BC549/BC550 NPN transistors for push-pull output stages and differential pairs
High-temperature operation	Junction rating up to +150 °C supports reliability in enclosed industrial enclosures and automotive under-hood environments
Pb-free, RoHS-compliant	Meets EU Directive 2011/65/EU and halogen-free/BFR-free requirements for environmentally regulated production

Applications

Audio Preamp Stage	Signal Level Shifting
Use Scenario: Amplifying weak signals from electret microphones or piezoelectric sensors before ADC sampling. IC Role / Device Role / Timing Role: Low-noise PNP amplifier in common-emitter configuration with emitter degeneration. Use Value: 1.2 dB noise figure and 200–450 h_FE ensure high SNR and minimal distortion at 1–10 kHz.	Use Scenario: Converting logic-level signals between −5 V and 0 V domains in legacy analog interface circuits. IC Role / Device Role / Timing Role: Saturated PNP switch providing inverted level translation with fast turn-on/turn-off. Use Value: V_CE(sat) ≤ −300 mV at I_C/I_B = 20 ensures <100 mV drop during conduction, preserving signal headroom.
Differential Pair Input	Current Mirror Reference
Use Scenario: Forming the input stage of discrete op-amps or instrumentation amplifiers requiring matched gain and offset. IC Role / Device Role / Timing Role: One leg of a PNP-based long-tailed pair with matched BC559B_J35Z units. Use Value: Tight h_FE spread (Class B: 200–450) and low V_BE variation (<150 mV) enable sub-mV input offset.	Use Scenario: Providing stable bias current for LED drivers or analog comparators in temperature-variable environments. IC Role / Device Role / Timing Role: Active current source in Wilson or basic two-transistor mirror topology. Use Value: Stable h_FE and low ICBO (≤−15 nA) minimize current drift over −55 °C to +125 °C.

Audio Preamp Stage

Signal Level Shifting

Use Scenario: Amplifying weak signals from electret microphones or piezoelectric sensors before ADC sampling.

IC Role / Device Role / Timing Role: Low-noise PNP amplifier in common-emitter configuration with emitter degeneration.

Use Value: 1.2 dB noise figure and 200–450 h_FE ensure high SNR and minimal distortion at 1–10 kHz.

Use Scenario: Converting logic-level signals between −5 V and 0 V domains in legacy analog interface circuits.

IC Role / Device Role / Timing Role: Saturated PNP switch providing inverted level translation with fast turn-on/turn-off.

Use Value: V_CE(sat) ≤ −300 mV at I_C/I_B = 20 ensures <100 mV drop during conduction, preserving signal headroom.

Differential Pair Input

Current Mirror Reference

Use Scenario: Forming the input stage of discrete op-amps or instrumentation amplifiers requiring matched gain and offset.

IC Role / Device Role / Timing Role: One leg of a PNP-based long-tailed pair with matched BC559B_J35Z units.

Use Value: Tight h_FE spread (Class B: 200–450) and low V_BE variation (<150 mV) enable sub-mV input offset.

Use Scenario: Providing stable bias current for LED drivers or analog comparators in temperature-variable environments.

IC Role / Device Role / Timing Role: Active current source in Wilson or basic two-transistor mirror topology.

Use Value: Stable h_FE and low ICBO (≤−15 nA) minimize current drift over −55 °C to +125 °C.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC559CTA	Higher h_FE (420–800, Class C); otherwise identical electrical specs and TO-92-3 packaging	Better suited for high-gain, low-current amplification where bias stability at ultra-low I_C matters more than speed	Select BC559CTA when gain >400 is required at I_C < 1 mA; BC559B_J35Z preferred for balanced gain/noise trade-offs
BC558BTA	Lower V_CEO (−30 V same), but higher V_CBO = −50 V vs. −30 V; identical h_FE, f_T, and noise performance	More robust against collector-base overvoltage transients; suitable where V_CB stress exceeds −30 V	Choose BC558BTA if circuit includes inductive loads or unclamped switching nodes; BC559B_J35Z remains optimal for pure low-noise linear use

Compared with BC559CTA and BC558BTA, BC559B_J35Z delivers the most balanced combination of gain linearity, noise floor, and thermal stability for general-purpose PNP amplification - making it ideal for cost-sensitive, high-volume audio and sensor signal chains where design margin must accommodate both performance and manufacturability.

Availability

BC559B_J35Z is available at Aetrix Electronics and suitable for audio preamplifiers, discrete sensor interfaces, and industrial signal conditioning circuits requiring stable component supply and long-term obsolescence management.

Supply support for BC559B_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 management, analog, and sensing solutions for automotive, industrial, and consumer markets.

The BC559B_J35Z belongs to onsemi's legacy BC5xx family of general-purpose bipolar transistors, engineered for reliable linear amplification and switching in cost-sensitive, high-reliability discrete designs.

FAQ

What is the maximum junction temperature for BC559B_J35Z?

The BC559B_J35Z has a maximum junction temperature (T_J) of +150 °C, as specified in the Absolute Maximum Ratings table. This allows sustained operation in thermally constrained environments such as sealed industrial enclosures or automotive under-dash modules, provided PCB layout and heatsinking maintain T_J within limit. Derating begins at 4.0 mW/°C above 25 °C ambient.

Is BC559B_J35Z RoHS compliant and lead-free?

Yes, BC559B_J35Z is Pb-free, halogen-free, and BFR-free, fully compliant with EU RoHS Directive 2011/65/EU. The device uses lead-free plating on its TO-92-3 leads and meets onsemi's environmental material specifications per the official datasheet revision dated June 2024.

What is the noise figure specification for BC559B_J35Z?

The BC559B_J35Z has a noise figure 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. This low-noise performance is explicitly documented for BC559 and BC560 variants in the Electrical Characteristics table and makes BC559B_J35Z suitable for microphone preamplifiers and precision sensor front-ends.

How does BC559B_J35Z differ from BC556BTA?

BC559B_J35Z differs from BC556BTA primarily in voltage ratings and noise optimization: BC556BTA has V_CEO = −65 V and is optimized for high-voltage switching, while BC559B_J35Z has V_CEO = −30 V and is specifically characterized for low-noise amplification (1.2–4.0 dB NF). Both share TO-92-3 packaging and Class B h_FE, but their application focus and absolute maximum ratings are distinct.

What is the pin configuration for BC559B_J35Z in TO-92-3 package?

The BC559B_J35Z uses standard TO-92-3 pinout: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter - confirmed by the Marking Diagram and Mechanical Case Outline (Case 135AR) in the official onsemi datasheet. This matches industry-standard orientation when viewing the flat side of the package with leads pointing downward and left-to-right labeling.

BC559B_J35Z Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-226-3, TO-92-3 (TO-226AA) Formed Leads

Packaging:: Bulk

Product Status:: Obsolete

Transistor Type:: PNP

Current - Collector (Ic) (Max):: 100 mA

Voltage - Collector Emitter Breakdown (Max):: 30 V

Vce Saturation (Max) @ Ib, Ic:: 650mV @ 5mA, 100mA

Current - Collector Cutoff (Max):: 15nA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 200 @ 2mA, 5V

Power - Max:: 500 mW

Frequency - Transition:: 150MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92-3

BC559B_J35Z FAQ

1.How can I place an order for BC559B_J35Z through Aetrix?

Please submit a Request for Quotation (RFQ) for BC559B_J35Z on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for BC559B_J35Z reliable?

The price and inventory of BC559B_J35Z are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC559B_J35Z is usually 5 days.

3.What payment methods are accepted for BC559B_J35Z?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC559B_J35Z transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC559B_J35Z?

BC559B_J35Z orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC559B_J35Z order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for BC559B_J35Z?

For technical support, including BC559B_J35Z datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC559B_J35Z requirements.

6.How does Aetrix verify that BC559B_J35Z is sourced from the original manufacturer or authorized distributors?

All BC559B_J35Z products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that BC559B_J35Z meets industry standards.

7.What is the process for return or replacement of BC559B_J35Z?

All BC559B_J35Z units undergo pre-shipment inspection (PSI). If there is an issue with BC559B_J35Z, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The BC559B_J35Z part is unused and in its original packaging.

Return procedure for BC559B_J35Z:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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