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onsemi BC559ATA
- Part No.:
- BC559ATA
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Datasheet:
-
BC559ATA.pdf
- Description:
- TRANS PNP 30V 0.1A TO-92-3
- Quantity:
- Payment:
- Shipping:
Inventory:7,456
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Product details
Overview
BC559ATA from onsemi is a PNP epitaxial silicon transistor optimized for low-noise amplification and general-purpose switching, with VCEO = −30 V, IC = −100 mA, hFE = 420–800 (Class C), fT = 150 MHz, and VBE(on) = −600 to −750 mV at IC = −2 mA - used in audio preamplifier stages, sensor signal conditioning, and discrete logic interface circuits.
For engineers reviewing the BC559ATA datasheet, pinout, applications, or equivalent options, key selection criteria include its low-noise performance (NF = 1.2–4.0 dB at 30–15 kHz), TO-92-3 package compatibility, complementary pairing with BC549/BC550, and Class C hFE gain binning for precision biasing.
Technical Context
The BC559ATA operates as a medium-speed, low-noise PNP bipolar junction transistor with a maximum junction temperature of 150°C and thermal resistance RJA = 250°C/W. Its design targets analog signal paths where noise figure and gain linearity are critical, especially under VCE = −5 V and IC = −200 µA to −10 mA conditions.
It features a fixed three-terminal structure (Collector–Base–Emitter) in TO-92-3 case 135AR, with absolute ratings defined for pulsed (ICP = −200 mA) and DC operation. The device is Pb-free, RoHS-compliant, and specified for operation across −65°C to +150°C storage range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −30 V - supports rail-to-rail operation in negative-supply amplifier stages up to 30 V collector-emitter differential. |
| IC (DC) | −100 mA - enables drive capability for small-signal loads including LED indicators and relay coils. |
| hFE (Class C) | 420–800 - ensures stable DC biasing in high-gain amplifier configurations without external feedback trimming. |
| fT | 150 MHz - allows use in RF front-end buffers and wideband audio amplifiers up to mid-VHF frequencies. |
| NF | 1.2–4.0 dB (30–15 kHz) - meets low-noise requirements for microphone preamps and instrumentation amplifiers. |
| VBE(on) | −600 to −750 mV @ IC = −2 mA - simplifies base resistor calculation for predictable turn-on in discrete switch designs. |
| PD | 500 mW @ TA = 25°C - defines thermal derating limit for continuous operation on standard FR-4 PCBs. |
Pinout & Package
BC559ATA is housed in a TO-92-3 plastic package (case 135AR), lead-formed configuration, with standardized pin assignment: Pin 1 = Collector, Pin 2 = Base, Pin 3 = Emitter.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Collector) | Current sink node | Connected to negative supply rail in common-emitter amplifiers; handles full load current path. |
| 2 (Base) | Control input | Receives bias current to regulate conduction; requires series resistor to limit IB ≤ −200 mA peak. |
| 3 (Emitter) | Reference terminal | Typically tied to ground or positive rail in PNP configurations; sets voltage reference for VBE threshold. |
Key Features
| Feature | Design Value |
|---|---|
| Low-noise amplification | NF = 1.2–4.0 dB at audio band (30–15 kHz), enabling clean signal gain in mic preamp and sensor front-ends. |
| High DC current gain | hFE = 420–800 (Class C) ensures minimal base drive requirement and stable quiescent point in linear stages. |
| Complementary pairing | Designed as PNP counterpart to BC549/BC550 NPN transistors, supporting matched push-pull and differential pair layouts. |
| Pb-free & RoHS compliance | Meets global environmental regulations without compromising thermal or electrical performance in reflow soldering processes. |
Applications
| Audio Preamp Stage | Sensor Signal Conditioning |
|---|---|
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: NF = 1.2–4.0 dB minimizes added noise floor, preserving SNR in sub-10 mV input signals. | Use Scenario: Converting high-impedance analog outputs from temperature or pressure transducers into buffered voltage levels. IC Role / Device Role / Timing Role: Discrete emitter-follower buffer providing impedance transformation and DC level shifting. Use Value: hFE ≥ 420 ensures low output impedance (< 50 Ω) while maintaining linearity over −20°C to +70°C. |
| Discrete Logic Interface | LED/Relay Driver |
Use Scenario: Level-shifting TTL/CMOS logic outputs to drive negative-rail referenced control lines in industrial PLC modules. IC Role / Device Role / Timing Role: Saturated PNP switch translating 0/3.3 V logic to −5 V/0 V active-low outputs. Use Value: VCE(sat) ≤ −300 mV @ IC = −10 mA ensures < 0.3 V drop during conduction, reducing power loss. | Use Scenario: Driving indicator LEDs or small 5 V relays from microcontroller GPIO pins with open-drain or active-low outputs. IC Role / Device Role / Timing Role: Current-sinking switch with base resistor limiting IB to achieve forced β = 20 for reliable saturation. Use Value: IC = −100 mA rating supports direct drive of 20 mA LEDs or 40 mA relay coils without heat sinking. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC559BTA | Lower hFE range (200–450, Class B) and identical VCEO/IC/NF specs. | Suitable where moderate gain suffices and tighter hFE tolerance reduces calibration effort. | Select BC559BTA when consistent mid-range gain is preferred over high-gain variability. |
| BC559CTA | Same package and pinout; hFE min = 420 (Class C), but marked as discontinued per onsemi documentation. | Not recommended for new designs due to obsolescence status; limited long-term availability. | Prefer BC559ATA over BC559CTA for production continuity and lifecycle support. |
Compared with BC559BTA and BC559CTA, the BC559ATA offers the highest guaranteed hFE (420–800), ensuring robust bias stability in high-gain analog stages, while avoiding the discontinuation risk of BC559CTA and the lower gain ceiling of BC559BTA.
Availability
BC559ATA is available at Aetrix Electronics and suitable for audio preamplifier circuits, sensor interface modules, and discrete logic-level translation requiring stable component supply and long-term manufacturability.
Supply support for BC559ATA 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 manufacturer specializing in energy-efficient power management, analog, and sensing solutions for automotive, industrial, and consumer markets.
The BC559ATA belongs to the BC556–BC560 PNP transistor family, designed for low-noise amplification and general-purpose switching in cost-sensitive, space-constrained applications using through-hole assembly.
FAQ
What is the maximum collector-emitter voltage rating for BC559ATA?
The BC559ATA has a maximum collector-emitter voltage (VCEO) rating of −30 V. This value is confirmed in the Absolute Maximum Ratings table of the official onsemi datasheet (Rev. 3, June 2024). Exceeding this voltage may cause irreversible breakdown. The BC559ATA is therefore suited for low-voltage negative-rail systems such as ±15 V op-amp supplies or −24 V industrial I/O interfaces.
Is BC559ATA RoHS compliant and lead-free?
Yes, BC559ATA is RoHS compliant and lead-free, as explicitly stated in the Features section of the onsemi datasheet. It uses halogen-free and BFR-free materials in its TO-92-3 case 135AR package. This compliance applies to both manufacturing and end-of-life handling, making BC559ATA suitable for environmentally regulated markets including EU and China RoHS jurisdictions.
What is the noise figure specification for BC559ATA?
The BC559ATA has a noise figure (NF) of 1.2–4.0 dB measured at VCE = −5 V, IC = −200 µA, f = 30–15,000 Hz, and RG = 2 kΩ. This specification is documented in the Electrical Characteristics table under "NF" for BC559/BC560 variants. The low NF makes BC559ATA appropriate for first-stage amplification in audio and precision analog signal chains.
How does BC559ATA differ from BC559BTA?
The BC559ATA and BC559BTA share identical package, pinout, and absolute ratings, but differ in hFE classification: BC559ATA is Class C (hFE = 420–800), while BC559BTA is Class B (hFE = 200–450). This means BC559ATA delivers higher and more consistent DC current gain, beneficial for high-gain amplifier biasing and low-base-drive switching applications.
What is the thermal resistance (RJA) of BC559ATA?
The BC559ATA has a junction-to-ambient thermal resistance (RJA) of 250°C/W under standard test conditions (FR-4 PCB, 76 mm × 114 mm, minimum land pattern). This value is listed in the Thermal Characteristics table and determines safe power dissipation limits: at 25°C ambient, max continuous power is 500 mW, derating by 4.0 mW/°C above that temperature.
BC559ATA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-226-3, TO-92-3 (TO-226AA) Formed Leads
- Packaging:
- Tape & Box (TB)
- 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:
- 110 @ 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
BC559ATA FAQ
1.How can I place an order for BC559ATA through Aetrix?
Please submit a Request for Quotation (RFQ) for BC559ATA 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 BC559ATA reliable?
The price and inventory of BC559ATA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC559ATA is usually 5 days.
3.What payment methods are accepted for BC559ATA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC559ATA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BC559ATA?
BC559ATA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BC559ATA 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 BC559ATA?
For technical support, including BC559ATA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC559ATA requirements.
6.How does Aetrix verify that BC559ATA is sourced from the original manufacturer or authorized distributors?
All BC559ATA 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 BC559ATA meets industry standards.
7.What is the process for return or replacement of BC559ATA?
All BC559ATA units undergo pre-shipment inspection (PSI). If there is an issue with BC559ATA, 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 BC559ATA part is unused and in its original packaging.
Return procedure for BC559ATA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BC559ATA Tags
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MMBT3906LT1G
onsemi
-
MMBT3904-7-F
Diodes Incorporated
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MMBT3904LT1G
onsemi
-
MMBT3906-7-F
Diodes Incorporated
-
MMBT3904-TP
Micro Commercial Co
-
MMBT2222A-7-F
Diodes Incorporated
-
BC846BLT1G
onsemi
-
BC847B,215
Nexperia USA Inc.
-
SMMBT3904LT1G
onsemi
-
MMBT2222A-TP
Micro Commercial Co
-
MMBTA06LT1G
onsemi
-
MMBT2222ALT1G
onsemi
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