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onsemi BCX71K_D87Z
- Part No.:
- BCX71K_D87Z
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BCX71K_D87Z.pdf
- Description:
- TRANS PNP 45V 0.5A SOT-23-3
- Quantity:
- Payment:
- Shipping:
Inventory:3,856
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Product details
Overview
BCX71K_D87Z from ON Semiconductor is a PNP general-purpose amplifier transistor in SOT-23 package, rated for -45 V VCEO, -500 mA IC, and 350 mW power dissipation, designed for high-current-gain linear amplification and switching up to 300 mA collector current.
For engineers reviewing the BCX71K_D87Z datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, thermal behavior, saturation characteristics, noise figure, and timing performance - all confirmed for the exact BCX71K_D87Z marking variant in SOT-23.
Technical Context
This PNP bipolar junction transistor uses silicon planar epitaxial process (Fairchild Process 68) and is optimized for high DC current gain (hFE = 380–630 at IC = -2.0 mA) with low VCE(sat) (-0.06 V min at IC = -10 mA). It operates across -55°C to +150°C junction temperature range and exhibits 6.0 pF Cob at VCB = -10 V.
Its 6.0 dB noise figure at IC = -0.2 mA and 1 kHz makes it suitable for low-noise preamplifier stages; turn-on/turn-off times (150 ns / 800 ns) support moderate-speed switching in discrete logic and driver circuits.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | -45 V - Maximum reverse-biased collector-emitter voltage before breakdown; defines safe operating voltage headroom in PNP switch or amplifier configurations. |
| IC (max) | -500 mA - Continuous collector current limit; supports load switching and amplification up to 300 mA with stable hFE. |
| hFE | 380–630 @ IC = -2.0 mA - High DC current gain enables low-base-drive designs in discrete gain stages and current mirrors. |
| VCE(sat) | -0.06 V min @ IC = -10 mA - Low saturation voltage minimizes conduction loss in saturated-switch applications. |
| PD | 350 mW @ TA = 25°C - Power dissipation rating determines thermal derating (2.8 mW/°C) and PCB copper area requirements. |
| NF | 6.0 dB @ IC = -0.2 mA - Confirmed noise performance for audio and sensor signal conditioning where low-noise BJT topology is preferred. |
| fT | 250 MHz typical - Gain-bandwidth product supports RF front-end and wideband analog signal paths up to ~100 MHz. |
Pinout & Package
SOT-23 (TO-236AB) 3-lead surface-mount plastic package with standard JEDEC outline; compact footprint (2.92 mm × 1.30 mm × 1.00 mm), gull-wing leads, and thermal pad not present. Marking "BK" identifies BCX71K_D87Z on top surface.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current source terminal for PNP operation | Connected to higher potential rail; base-emitter forward bias initiates conduction; polarity critical for correct circuit biasing. |
| 2 (Base) | Control input for minority-carrier injection | Receives negative current to turn device on; requires current-limiting resistor; sensitive to ESD due to thin oxide layer. |
| 3 (Collector) | Current sink terminal | Connected to load and lower-potential node; carries full emitter current minus base current; voltage swing limited by VCEO. |
Key Features
| Feature | Design Value |
|---|---|
| High hFE at low IC | Min 100 at IC = -10 μA - Enables micro-power bias networks and ultra-low-input-current amplifiers. |
| Low VCE(sat) | -0.12 V max @ IC = -50 mA - Reduces power loss and self-heating in high-current switching nodes. |
| Low noise figure | 6.0 dB @ 1 kHz - Supports precision analog front-ends where op-amp alternatives may introduce offset or bandwidth limitations. |
| Fast switching | 150 ns ton, 800 ns toff - Suitable for pulse-width modulation drivers and digital logic level translation below 1 MHz. |
| Wide temperature range | -55°C to +150°C TJ - Validated for automotive under-hood, industrial motor control, and outdoor power electronics. |
Applications
| Audio Pre-Amplifier Stage | LED Current Sink Driver |
|---|---|
|
Use Scenario: Discrete low-noise gain stage preceding an audio ADC in battery-powered portable equipment. IC Role / Device Role / Timing Role: PNP amplifier providing 20–40 dB voltage gain with minimal added noise in the 20 Hz–20 kHz band. Use Value: 6.0 dB NF and high hFE allow single-transistor design without feedback compensation, reducing component count and board space. |
Use Scenario: Constant-current sink for high-brightness indicator LEDs in industrial HMIs with 12 V supply rails. IC Role / Device Role / Timing Role: Linear current regulator using emitter-degeneration resistor, controlled via PWM-modulated base drive. Use Value: -500 mA IC rating and -0.12 V VCE(sat) enable efficient 350 mA LED drive with <100 mW dissipation at full load. |
| Level Translation Interface | Discrete Logic Inverter |
|
Use Scenario: Converting 3.3 V CMOS logic outputs to interface with legacy 5 V or 12 V TTL-compatible inputs. IC Role / Device Role / Timing Role: PNP-based active pull-up inverting buffer with adjustable output threshold via base resistor network. Use Value: Fast 150 ns ton ensures sub-microsecond response; low VBE(on) (-0.60 V) guarantees reliable turn-on with weak MCU GPIOs. |
Use Scenario: Building non-inverting or inverting logic gates in repair scenarios or custom control panels where IC-level integration is impractical. IC Role / Device Role / Timing Role: Saturated-switch inverter with fixed bias network, delivering rail-to-rail output swing compatible with 5 V logic families. Use Value: Confirmed -0.25 V VCE(sat) max ensures strong LOW-state drive; hFE > 380 allows direct MCU GPIO drive without external base amplifier. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP general-purpose amplifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC807-40 | Higher hFE (250–630), same SOT-23 package, but VCEO = -45 V and IC = -500 mA identical; slightly higher RθJA (400°C/W). | Preferred where tighter hFE distribution required; less suitable for high-ambient thermal environments without derating. | Select BC807-40 when statistical gain consistency across production batches is critical; verify thermal margin at 100°C ambient. |
| MMBT4403 | Lower hFE (100–300), same VCEO/IC ratings, but higher VCE(sat) (-0.75 V max @ IC = -150 mA); identical SOT-23 footprint. | Better suited for digital switching than linear amplification; higher saturation loss limits efficiency in analog current sources. | Choose MMBT4403 only for saturated-switch roles where gain tolerance is secondary; avoid in low-noise or high-linearity analog paths. |
Compared with BCX71K_D87Z, BC807-40 offers superior hFE consistency for precision biasing, while MMBT4403 trades gain and noise for broader availability and lower cost - making BCX71K_D87Z optimal for balanced analog/switching use cases requiring verified 6.0 dB NF and 250 MHz fT.
Availability
BCX71K_D87Z is available at Aetrix Electronics and suitable for industrial motor control interfaces, automotive body electronics, and consumer audio subsystems requiring stable component supply and long-term obsolescence management.
Supply support for BCX71K_D87Z 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 supplier specializing in energy-efficient power management, analog, sensors, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
BCX71K_D87Z belongs to ON Semiconductor's legacy general-purpose bipolar transistor portfolio, originally developed by Fairchild for robust, cost-effective discrete amplification and switching in high-volume industrial and consumer applications.
FAQ
What is the maximum continuous collector current rating for BCX71K_D87Z?
The BCX71K_D87Z is rated for -500 mA continuous collector current (IC) at TA = 25°C. Derating applies above 25°C ambient per its 2.8 mW/°C thermal coefficient. This rating supports reliable operation in LED drivers and relay drivers where peak currents reach 300 mA with margin.
Does BCX71K_D87Z have a documented noise figure, and under what conditions is it measured?
Yes, BCX71K_D87Z has a specified noise figure of 6.0 dB, measured at IC = -0.2 mA, VCE = -5.0 V, RS = 2.0 kΩ, f = 1.0 kHz, and BW = 200 Hz. This value is confirmed in the original Fairchild BCX71K datasheet Rev. 1.1.0 and remains valid for BCX71K_D87Z as a marking variant.
What is the pin configuration of BCX71K_D87Z in the SOT-23 package?
BCX71K_D87Z uses standard SOT-23 pinout: Pin 1 = Emitter, Pin 2 = Base, Pin 3 = Collector. This matches JEDEC TO-236AB layout and is verified in Fairchild's MA03D package drawing. The top-side marking "BK" aligns with this pin assignment.
Can BCX71K_D87Z be used in linear amplifier applications, and what gain performance is guaranteed?
Yes, BCX71K_D87Z is explicitly designed for linear amplification, with guaranteed hFE = 380–630 at IC = -2.0 mA and VCE = -5.0 V. Its low VCE(sat) and 6.0 dB noise figure make it suitable for Class-A preamplifier stages where discrete BJT topology is preferred over op-amps.
What is the absolute maximum VCEO rating for BCX71K_D87Z, and how does it impact circuit design?
The absolute maximum VCEO for BCX71K_D87Z is -45 V, meaning the collector must remain at least 45 V below the emitter voltage to avoid breakdown. This defines the maximum supply rail differential in PNP switch configurations and sets headroom limits in high-side driver designs.
BCX71K_D87Z 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):
- 500 mA
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 550mV @ 1.25mA, 50mA
- Current - Collector Cutoff (Max):
- 20nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 380 @ 2mA, 5V
- Power - Max:
- 350 mW
- Frequency - Transition:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
BCX71K_D87Z FAQ
1.How can I place an order for BCX71K_D87Z through Aetrix?
Please submit a Request for Quotation (RFQ) for BCX71K_D87Z 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 BCX71K_D87Z reliable?
The price and inventory of BCX71K_D87Z are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BCX71K_D87Z is usually 5 days.
3.What payment methods are accepted for BCX71K_D87Z?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BCX71K_D87Z transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BCX71K_D87Z?
BCX71K_D87Z orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BCX71K_D87Z 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 BCX71K_D87Z?
For technical support, including BCX71K_D87Z datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BCX71K_D87Z requirements.
6.How does Aetrix verify that BCX71K_D87Z is sourced from the original manufacturer or authorized distributors?
All BCX71K_D87Z 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 BCX71K_D87Z meets industry standards.
7.What is the process for return or replacement of BCX71K_D87Z?
All BCX71K_D87Z units undergo pre-shipment inspection (PSI). If there is an issue with BCX71K_D87Z, 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 BCX71K_D87Z part is unused and in its original packaging.
Return procedure for BCX71K_D87Z:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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