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

onsemi BC859CLT1

Name: BC859CLT1
Brand: onsemi
SKU: BC859CLT1
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BC859CLT1

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-236-3, SC-59, SOT-23-3

Datasheet:: BC859CLT1.pdf

Description:: TRANS PNP 30V 0.1A SOT23-3

Quantity:: RFQ Add To RFQ list

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Product details

Overview

BC859CLT1 from onsemi is a PNP silicon general-purpose transistor in SOT-23 package, rated for −30 V V_CEO, −100 mA I_C continuous, 420–800 h_FE (at I_C = −2.0 mA), 100 MHz f_T, and 4.5 pF C_ob. It serves as a low-power switching or linear amplification device in bias networks, level shifters, and discrete logic interfaces.

For engineers reviewing the BC859CLT1 datasheet, pinout, applications, or equivalent options, key selection criteria include its PNP polarity, SOT-23 footprint compatibility, guaranteed h_FE range (C-grade), −30 V breakdown rating, and AEC-Q101 qualification status for automotive use cases.

Technical Context

The BC859CLT1 operates as a discrete bipolar junction transistor with fixed PNP polarity and current-controlled gain. Its DC current gain (h_FE) is specified at two test points: 420–800 at I_C = −2.0 mA/V_CE = −5.0 V (C-grade), and 270–520 at I_C = −10 mA/V_CE = −5.0 V - confirming high-beta performance in low-current biasing roles.

It exhibits V_CE(sat) ≤ −0.65 V at I_C = −100 mA/I_B = −5.0 mA and V_BE(sat) ≤ −0.9 V under same conditions, supporting robust saturation in switching applications. Noise figure is 4.0 dB at I_C = −0.2 mA, making it suitable for low-noise preamplifier stages where PNP topology is required.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	−30 V - Maximum collector-emitter voltage before breakdown; defines safe operating voltage headroom in PNP load-switch or level-shift circuits.
I_C Continuous	−100 mA - Absolute maximum DC collector current; sets upper limit for steady-state current handling in bias networks or driver stages.
h_FE Range (C-grade)	420–800 at I_C = −2.0 mA - Tight high-gain bin enabling stable bias point setting with minimal base drive in low-power analog circuits.
f_T	100 MHz - Unity-gain frequency confirming usable bandwidth up to ~10–20 MHz in small-signal amplification applications.
C_ob	4.5 pF at V_CB = −10 V - Output capacitance affecting high-frequency response and switching speed in RF or fast digital interface designs.
V_CE(sat)	≤ −0.65 V at I_C = −100 mA/I_B = −5.0 mA - Low saturation voltage minimizes power loss and improves efficiency in saturated-switch configurations.
NF	4.0 dB at I_C = −0.2 mA - Confirmed low-noise performance suitable for front-end PNP amplifiers in sensor signal conditioning paths.

Pinout & Package

SOT-23 (TO-236) surface-mount package, 2.90 mm × 1.30 mm × 1.00 mm body size, 1.90 mm lead pitch. RoHS-compliant, Pb-free, halogen-free/BFR-free construction.

Pin/Terminal	Circuit Role	Design Meaning
1	Base	Current-controlled input node; requires external bias resistor network to establish operating point in active or saturation region.
2	Emitter	Common terminal for PNP configuration; connected to higher potential rail (e.g., V_CC) in typical switch or amplifier topologies.
3	Collector	Output terminal; sinks current when biased on; connects to load or next stage input in common-emitter or common-base arrangements.

Key Features

Feature	Design Value
AEC-Q101 qualified	Validated for automotive electronics per stress test requirements, enabling use in engine control, body electronics, and ADAS subsystems.
C-grade h_FE binning	Guaranteed 420–800 h_FE at low current ensures predictable DC bias stability across temperature and unit-to-unit variation.
Low V_CE(sat)	≤ −0.65 V at high drive enables efficient switching in battery-powered or thermally constrained applications.
100 MHz f_T	Supports audio-frequency amplification and medium-speed digital signal routing without significant gain roll-off.
4.0 dB noise figure	Enables use in low-level signal amplification where PNP topology is preferred for phase or supply rail constraints.

Applications

Automotive Door Module	Industrial Sensor Bias Network
Use Scenario: Level-shifting and signal inversion in LIN bus interface circuitry within door control units. IC Role / Device Role / Timing Role: PNP transistor used as active pull-up and inverter stage between microcontroller GPIO and LIN transceiver input. Use Value: −30 V V_CEO withstands automotive load-dump transients; AEC-Q101 qualification ensures reliability in harsh vehicle environments.	Use Scenario: Providing stable emitter-follower bias current to bridge-based pressure or temperature sensors. IC Role / Device Role / Timing Role: High-h_FE PNP current source delivering precise quiescent current to sensor Wheatstone bridge arms. Use Value: C-grade h_FE (420–800) ensures consistent bias current over temperature, minimizing sensor offset drift.
Consumer Audio Preamp Stage	Medical Wearable Signal Conditioning
Use Scenario: Low-noise PNP input stage in portable headphone amplifier front-end. IC Role / Device Role / Timing Role: Small-signal amplifier configured in common-emitter mode to boost weak line-level signals. Use Value: 4.0 dB noise figure and 100 MHz f_T preserve audio fidelity up to 20 kHz with minimal added noise.	Use Scenario: Amplifying microvolt-level bio-potential signals (e.g., ECG leads) in compact wearable monitors. IC Role / Device Role / Timing Role: First-stage PNP amplifier providing high-input-impedance, low-noise gain before ADC sampling. Use Value: Low V_BE(on) (−0.75 V typ.) and tight h_FE binning support stable DC operating point critical for baseline stability.

Automotive Door Module

Industrial Sensor Bias Network

Use Scenario: Level-shifting and signal inversion in LIN bus interface circuitry within door control units.

IC Role / Device Role / Timing Role: PNP transistor used as active pull-up and inverter stage between microcontroller GPIO and LIN transceiver input.

Use Value: −30 V V_CEO withstands automotive load-dump transients; AEC-Q101 qualification ensures reliability in harsh vehicle environments.

Use Scenario: Providing stable emitter-follower bias current to bridge-based pressure or temperature sensors.

IC Role / Device Role / Timing Role: High-h_FE PNP current source delivering precise quiescent current to sensor Wheatstone bridge arms.

Use Value: C-grade h_FE (420–800) ensures consistent bias current over temperature, minimizing sensor offset drift.

Consumer Audio Preamp Stage

Medical Wearable Signal Conditioning

Use Scenario: Low-noise PNP input stage in portable headphone amplifier front-end.

IC Role / Device Role / Timing Role: Small-signal amplifier configured in common-emitter mode to boost weak line-level signals.

Use Value: 4.0 dB noise figure and 100 MHz f_T preserve audio fidelity up to 20 kHz with minimal added noise.

Use Scenario: Amplifying microvolt-level bio-potential signals (e.g., ECG leads) in compact wearable monitors.

IC Role / Device Role / Timing Role: First-stage PNP amplifier providing high-input-impedance, low-noise gain before ADC sampling.

Use Value: Low V_BE(on) (−0.75 V typ.) and tight h_FE binning support stable DC operating point critical for baseline stability.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
BC857CLT1G	V_CEO = −45 V, h_FE = 420–800 at I_C = −2 mA, same SOT-23 package and pinout.	Higher breakdown margin suits 3.3 V/5 V logic interfacing with higher supply rails; identical thermal and gain behavior.	Select when system voltage exceeds 30 V but layout must remain unchanged.
MMBT3906LT1G	V_CEO = −40 V, h_FE = 100–300 (standard grade), slightly higher C_ob (8 pF), same SOT-23 footprint.	Broader h_FE spread increases design margining effort; lower f_T (~250 MHz) but higher V_CEO supports wider supply range.	Choose for cost-sensitive industrial designs where tighter h_FE tolerance is not required.

Compared with BC859CLT1, BC857CLT1G offers higher voltage tolerance without layout change, while MMBT3906LT1G trades h_FE consistency for broader availability and lower cost - both require validation of noise and switching timing in final circuit implementation.

Availability

BC859CLT1 is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, portable audio systems, and medical wearable signal chains requiring stable component supply, AEC-Q101 compliance, and SOT-23 footprint continuity.

Supply support for BC859CLT1 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 is a global semiconductor supplier specializing in energy-efficient electronics, with leadership in automotive, industrial, cloud, and sensing solutions.

The BC859CLT1 belongs to onsemi's BC856ALT1G Series of general-purpose PNP transistors, designed for reliable, high-volume applications in automotive control modules and industrial signal conditioning where AEC-Q101 compliance and tight parametric binning are essential.

FAQ

What is the maximum collector-emitter voltage rating for BC859CLT1?

The BC859CLT1 has a maximum collector-emitter voltage (V_CEO) rating of −30 V, verified per onsemi's April 2023 datasheet revision. This rating applies at T_A = 25°C and defines the absolute upper limit for safe DC operation before avalanche breakdown occurs. Exceeding this voltage risks permanent device failure, especially under transient conditions without clamping protection. The BC859CLT1 datasheet confirms this value in both Maximum Ratings and Electrical Characteristics tables.

Is BC859CLT1 AEC-Q101 qualified?

Yes, BC859CLT1 is AEC-Q101 qualified and PPAP capable, as explicitly stated in the "Features" section of the official onsemi BC856ALT1G Series datasheet. This qualification covers stress tests including HTGB, AC/DC life test, temperature cycling, and mechanical shock - validating suitability for automotive applications such as door modules, lighting controls, and body ECUs. The "S" and "NSV" prefix variants (e.g., NSVBC859BLT1G) are also AEC-Q101 certified, confirming the core BC859 series meets automotive reliability standards.

What is the h_FE range for BC859CLT1 at I_C = −2.0 mA?

The BC859CLT1 is binned to the "C" grade, with h_FE guaranteed between 420 and 800 when tested at I_C = −2.0 mA and V_CE = −5.0 V, per the Electrical Characteristics table in the onsemi datasheet. This high-gain bin enables precise biasing in low-current analog circuits and reduces base drive requirements in switching applications. The datasheet distinguishes this from "B" grade (270–520) and "A" grade (125–250), confirming BC859CLT1's position as the highest-gain variant in the BC859 family.

Does BC859CLT1 have the same pinout as BC857CLT1G?

Yes, BC859CLT1 uses Style 6 pinout (Pin 1 = Base, Pin 2 = Emitter, Pin 3 = Collector) in the SOT-23 package, matching BC857CLT1G and all members of the BC856ALT1G Series. This is confirmed in the "MECHANICAL CASE OUTLINE" section of the datasheet, which specifies Style 6 for PNP transistors in this family. No PCB layout change is needed when substituting between BC859CLT1 and BC857CLT1G, though voltage and gain differences must be validated in-circuit.

What is the thermal resistance R_JA of BC859CLT1 on FR-5 board?

The BC859CLT1 has a junction-to-ambient thermal resistance (R_JA) of 556°C/W when mounted on an FR-5 board (1.0 × 0.75 × 0.062 in), per the Thermal Characteristics table in the onsemi datasheet. This value assumes natural convection and standard copper pour; actual R_JA improves with enhanced PCB copper area or forced airflow. Derating is required above 25°C at 1.8 mW/°C, limiting usable power dissipation to approximately 135 mW at 100°C ambient.

BC859CLT1 Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-236-3, SC-59, SOT-23-3

Packaging:: Tape & Reel (TR)

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:: 420 @ 2mA, 5V

Power - Max:: 300 mW

Frequency - Transition:: 100MHz

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

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23-3 (TO-236)

BC859CLT1 FAQ

1.How can I place an order for BC859CLT1 through Aetrix?

Please submit a Request for Quotation (RFQ) for BC859CLT1 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 BC859CLT1 reliable?

The price and inventory of BC859CLT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BC859CLT1 is usually 5 days.

3.What payment methods are accepted for BC859CLT1?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BC859CLT1 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BC859CLT1?

BC859CLT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BC859CLT1 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 BC859CLT1?

For technical support, including BC859CLT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BC859CLT1 requirements.

6.How does Aetrix verify that BC859CLT1 is sourced from the original manufacturer or authorized distributors?

All BC859CLT1 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 BC859CLT1 meets industry standards.

7.What is the process for return or replacement of BC859CLT1?

All BC859CLT1 units undergo pre-shipment inspection (PSI). If there is an issue with BC859CLT1, 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 BC859CLT1 part is unused and in its original packaging.

Return procedure for BC859CLT1:

1.Submit a request within 90 days.

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

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