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

onsemi BC559BZL1

Name: BC559BZL1
Brand: onsemi
SKU: BC559BZL1
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BC559BZL1

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

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

Datasheet:: BC559BZL1.pdf

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

Quantity:: RFQ Add To RFQ list

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Inventory:16,000

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Product details

Overview

BC559BZL1 from ON Semiconductor is a PNP silicon low-noise general-purpose amplifier transistor in TO-92 package, with V_CEO = –30 V, I_C = –100 mA, h_FE = 100–180 (at I_C = –10 µA), f_T = 250 MHz, and NF = 0.5 dB (R_S = 2.0 kΩ). It serves as an audio preamplifier stage in battery-powered portable audio equipment.

For engineers reviewing the BC559BZL1 datasheet, pinout, applications, or equivalent options, key selection criteria include its low-noise performance at microamp bias, guaranteed h_FE binning (B grade), TO-92 mechanical compatibility, and thermal resistance (R_JA = 200 °C/W) for ambient-limited linear operation.

Technical Context

This device operates as a linear PNP bipolar junction transistor optimized for low-noise small-signal amplification. Its design emphasizes stable h_FE across collector currents from –10 µA to –2 mA, low base spreading resistance (~150 Ω), and minimal C_obo (2.5 pF) to preserve high-frequency gain integrity.

The BC559BZL1 shares the BC559 family's TO-92 pinout (E-B-C), specified thermal limits (T_J = –55 to +150 °C), and absolute maximum ratings including V_CBO = –30 V and P_D = 625 mW at T_A = 25 °C - derated linearly above that temperature.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	–30 V - Maximum safe voltage between collector and emitter with base open; defines usable supply headroom in common-emitter amplifier stages.
I_C (max)	–100 mA - Continuous DC collector current limit; sets upper bound for output stage drive capability in Class-A preamps.
h_FE (min/typ)	100 / 150 - DC current gain at I_C = –10 µA, V_CE = –5 V; ensures predictable bias stability in high-input-impedance circuits.
f_T	250 MHz - Transition frequency at I_C = –10 mA, V_CE = –5 V; supports wideband audio and low-MHz signal amplification without gain roll-off.
NF	0.5 dB - Noise figure at I_C = –200 µA, R_S = 2.0 kΩ, 1 kHz; enables high-SNR microphone preamplification in portable devices.
R_JA	200 °C/W - Junction-to-ambient thermal resistance in free-air; determines required heatsinking or power derating for sustained operation.

Pinout & Package

BC559BZL1 is housed in a standard TO-92 (Case 29–04, Style 17) plastic package with 3 leads, rated for operation from –55 °C to +150 °C junction temperature.

Pin/Terminal	Circuit Role	Design Meaning
1	Collector	Main current sink terminal; connected to negative supply rail in PNP common-emitter configurations.
2	Base	Control input; requires reverse-biased current (–I_B) to turn on; sensitive to ESD due to thin oxide layer.
3	Emitter	Current source terminal; typically tied to circuit ground or positive rail depending on topology (e.g., emitter-follower).

Key Features

Feature	Design Value
Low noise figure	0.5 dB at 1 kHz enables high-fidelity audio front-end design without added noise-cancelling circuitry.
Guaranteed h_FE binning (B grade)	h_FE = 100–180 ensures consistent DC bias point across production lots in discrete amplifier designs.
High f_T	250 MHz allows stable gain up to ~20 MHz, supporting ultrasonic sensor interfaces and broadband instrumentation.
TO-92 mechanical standardization	Enables drop-in replacement in legacy PCBs designed for BC556–BC559 series, reducing redesign effort.

Applications

Audio Preamp Stage	Low-Power Sensor Interface
Use Scenario: Amplifying weak signals from electret condenser microphones in Bluetooth headsets. IC Role / Device Role / Timing Role: PNP small-signal amplifier in common-emitter configuration with emitter degeneration. Use Value: 0.5 dB noise figure preserves SNR in battery-constrained 3.3 V systems where op-amps draw excessive quiescent current.	Use Scenario: Signal conditioning for thermistor-based temperature monitoring in smart thermostats. IC Role / Device Role / Timing Role: Discrete transconductance amplifier converting resistance change to voltage swing. Use Value: Stable h_FE over –25 to +70 °C ambient ensures repeatable gain calibration without software compensation.
DC Bias Reference Generator	Discrete Logic Level Shifter
Use Scenario: Generating precise –0.65 V reference for analog comparators in industrial control modules. IC Role / Device Role / Timing Role: Emitter-follower configured with fixed base voltage for low-output-impedance biasing. Use Value: V_BE(on) = –0.55 to –0.62 V (at I_C = –2 mA) provides predictable, temperature-compensated offset without trimming.	Use Scenario: Translating 5 V logic outputs to –3.3 V compatible levels in mixed-voltage FPGA I/O banks. IC Role / Device Role / Timing Role: Saturated switch in common-emitter inverter topology with pull-up to negative rail. Use Value: V_CE(sat) ≤ –0.25 V at I_C/I_B = 10 ensures clean logic low assertion below –3.0 V threshold.

Audio Preamp Stage

Low-Power Sensor Interface

Use Scenario: Amplifying weak signals from electret condenser microphones in Bluetooth headsets.

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

Use Value: 0.5 dB noise figure preserves SNR in battery-constrained 3.3 V systems where op-amps draw excessive quiescent current.

Use Scenario: Signal conditioning for thermistor-based temperature monitoring in smart thermostats.

IC Role / Device Role / Timing Role: Discrete transconductance amplifier converting resistance change to voltage swing.

Use Value: Stable h_FE over –25 to +70 °C ambient ensures repeatable gain calibration without software compensation.

DC Bias Reference Generator

Discrete Logic Level Shifter

Use Scenario: Generating precise –0.65 V reference for analog comparators in industrial control modules.

IC Role / Device Role / Timing Role: Emitter-follower configured with fixed base voltage for low-output-impedance biasing.

Use Value: V_BE(on) = –0.55 to –0.62 V (at I_C = –2 mA) provides predictable, temperature-compensated offset without trimming.

Use Scenario: Translating 5 V logic outputs to –3.3 V compatible levels in mixed-voltage FPGA I/O banks.

IC Role / Device Role / Timing Role: Saturated switch in common-emitter inverter topology with pull-up to negative rail.

Use Value: V_CE(sat) ≤ –0.25 V at I_C/I_B = 10 ensures clean logic low assertion below –3.0 V threshold.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC557B	Same TO-92 package, identical V_CEO, V_CBO, and I_C; h_FE min = 110 (slightly higher gain bin), NF = 0.6 dB.	Marginally higher noise; otherwise interchangeable in audio and bias circuits.	Select BC557B when tighter h_FE distribution is needed, but verify noise margin in ultra-low-level microphone paths.
MMBT5551	PNP counterpart to MMBT5401; V_CEO = –60 V, f_T = 100 MHz, NF = 5 dB - significantly noisier and lower bandwidth.	Higher voltage rating suits HV bias networks, but unsuitable for low-noise audio due to 10× higher NF.	Choose MMBT5551 only for non-critical switching or high-V_CE applications where noise and bandwidth are secondary.

Compared with BC557B and MMBT5551, the BC559BZL1 delivers optimal balance of low noise (0.5 dB), moderate voltage rating (–30 V), and guaranteed B-grade h_FE, making it preferred for precision analog front-ends where both gain consistency and signal fidelity matter.

Availability

BC559BZL1 is available at Aetrix Electronics and suitable for audio preamplifiers, low-power sensor interfaces, and discrete bias reference generators requiring stable component supply and long-term manufacturability.

Supply support for BC559BZL1 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power management, analog, and sensor solutions for automotive, industrial, and consumer markets.

The BC559BZL1 belongs to ON Semiconductor's legacy BC5xx PNP/NPN general-purpose transistor family, engineered for cost-sensitive, high-reliability linear amplification and switching in space-constrained through-hole applications.

FAQ

What is the maximum operating junction temperature for BC559BZL1?

The BC559BZL1 has a specified operating and storage junction temperature range of –55 °C to +150 °C. This allows reliable use in automotive under-hood environments and industrial enclosures without active cooling, provided power dissipation remains within derated limits per the R_JA = 200 °C/W specification.

Is BC559BZL1 pin-compatible with BC558 or BC557?

Yes, BC559BZL1 is fully pin-compatible with BC557 and BC558 in TO-92 package (pin 1 = collector, pin 2 = base, pin 3 = emitter). All share identical mechanical footprint and pinout, enabling direct substitution where voltage, current, and gain requirements align - though BC559BZL1's B-grade h_FE (100–180) differs from BC557's (110–220) and BC558's (180–450).

What is the typical noise figure of BC559BZL1 and under what conditions is it measured?

The BC559BZL1 has a typical noise figure of 0.5 dB, measured at I_C = –200 µA, V_CE = –5.0 Vdc, R_S = 2.0 kΩ, f = 1.0 kHz, and ∆f = 200 kHz. This value reflects its optimization for low-noise small-signal amplification in audio and precision analog front-ends.

Can BC559BZL1 be used in switching applications?

Yes, BC559BZL1 can operate in switching mode with V_CE(sat) ≤ –0.25 V at I_C/I_B = 10, but it is not optimized for high-speed digital switching. Its f_T = 250 MHz and moderate storage time make it suitable for <100 kHz toggle rates in power control or level-shifting, not RF or fast logic.

What is the DC current gain (h_FE) range for BC559BZL1 at I_C = –2.0 mA?

At I_C = –2.0 mA and V_CE = –5.0 Vdc, the BC559BZL1 exhibits h_FE = 150 (typical) with a minimum of 100 and maximum of 270 - consistent with its B-grade binning and documented in ON Semiconductor's BC559B/D datasheet revision 0.

BC559BZL1 Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

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

Packaging:: Bulk

Product Status:: Active

Transistor Type:: PNP

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

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

Vce Saturation (Max) @ Ib, Ic:: 250mV @ 500µA, 10mA

Current - Collector Cutoff (Max):: 100nA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 180 @ 2mA, 5V

Power - Max:: 625 mW

Frequency - Transition:: 250MHz

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-92

BC559BZL1 FAQ

1.How can I place an order for BC559BZL1 through Aetrix?

Please submit a Request for Quotation (RFQ) for BC559BZL1 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 BC559BZL1 reliable?

The price and inventory of BC559BZL1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC559BZL1 is usually 5 days.

3.What payment methods are accepted for BC559BZL1?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC559BZL1 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC559BZL1?

BC559BZL1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC559BZL1 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 BC559BZL1?

For technical support, including BC559BZL1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC559BZL1 requirements.

6.How does Aetrix verify that BC559BZL1 is sourced from the original manufacturer or authorized distributors?

All BC559BZL1 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 BC559BZL1 meets industry standards.

7.What is the process for return or replacement of BC559BZL1?

All BC559BZL1 units undergo pre-shipment inspection (PSI). If there is an issue with BC559BZL1, 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 BC559BZL1 part is unused and in its original packaging.

Return procedure for BC559BZL1:

1.Submit a request within 90 days.

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

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