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Nexperia USA Inc. BF821,215
- Part No.:
- BF821,215
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BF821,215.pdf
- Description:
- TRANS PNP 300V 0.05A TO-236AB
- Quantity:
- Payment:
- Shipping:
Inventory:4,358
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Product details
Overview
BF821 from Nexperia is a PNP high-voltage bipolar junction transistor in SOT23 package, designed for off-state voltage blocking up to −300 V with −50 mA collector current capability and DC current gain (hFE) ≥50 at −25 mA/−20 V; used in telephony line interface circuits requiring high breakdown and low leakage.
For engineers reviewing the BF821 datasheet, BF821 pinout, BF821 application, or BF821 equivalent, key selection criteria include verified VCEO = −300 V, IC = −50 mA, hFE ≥50, VCE(sat) ≤ −800 mV at −30 mA/−5 mA, and SOT23 thermal resistance of 500 K/W on standard PCB mounting.
Technical Context
The BF821 operates as a high-voltage PNP switch with open-base collector-emitter breakdown rated at −300 V and emitter-base breakdown limited to −5 V, enabling use in high-impedance, low-current biasing networks where voltage isolation dominates over power handling.
Its fT of 60 MHz and Cre of 1.6 pF at −30 V support moderate-speed switching in line-feed and ringing generator stages, while ICBO ≤ −10 nA at −200 V ensures minimal leakage under high reverse bias.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | −300 V: Maximum safe collector-emitter voltage with base open; enables direct connection to −200 V telephony line supplies without external clamping. |
| IC | −50 mA: Continuous collector current rating; sufficient for driving SLIC interface loads and relay coils in professional telecom equipment. |
| hFE | ≥50 at −25 mA/−20 V: Confirmed DC current gain ensures reliable base drive margin in linear and saturated switching modes. |
| VCE(sat) | ≤ −800 mV at −30 mA/−5 mA: Low saturation voltage minimizes power loss and heating during active switching in line-card protection circuits. |
| Cre | 1.6 pF at −30 V: Feedback capacitance limits high-frequency instability; supports stable operation up to 60 MHz transition frequency. |
| Rth(j-a) | 500 K/W on 1 cm² single-sided Cu PCB: Thermal resistance defines maximum power dissipation (250 mW) under standard board-mount conditions. |
Pinout & Package
SOT23 plastic surface-mounted package: 3-terminal, 1.9 mm pitch, 2.9 mm × 1.3 mm × 1.0 mm body; collector-connected tab for thermal relief on PCB.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Current-controlled input node; requires negative base current to forward-bias emitter-base junction and enable conduction. |
| 2 | Emitter (E) | High-side current source terminal; connected to most positive rail in PNP configuration; carries full load current. |
| 3 | Collector (C) | Output terminal tied to load and high-voltage supply; collector pad provides primary thermal path to PCB copper. |
Key Features
| Feature | Design Value |
|---|---|
| High VCEO rating | −300 V enables direct integration into −200 V telephony line feed circuits without series resistors or external Zener clamps. |
| Low ICBO leakage | ≤ −10 nA at −200 V ensures stable off-state blocking in high-impedance monitoring paths over temperature. |
| SOT23 footprint compatibility | Standard 1.9 mm pitch allows drop-in replacement in existing designs using BF820/BF822 NPN complements. |
| Controlled VCE(sat) | ≤ −800 mV at −30 mA/−5 mA guarantees predictable power loss and thermal rise in sustained on-state operation. |
Applications
| Telephony Line Interface | Professional Audio Signal Switching |
|---|---|
Use Scenario: High-voltage switching in analog telephone line card circuits for ring detection, off-hook sensing, and battery feed control. IC Role / Device Role / Timing Role: PNP high-side switch controlling −48 V to −200 V line potentials with precise current limiting and low leakage. Use Value: −300 V VCEO eliminates need for external voltage clamping components; 500 K/W Rth(j-a) supports continuous operation on compact PCBs. | Use Scenario: Muting and routing of balanced audio signals in broadcast mixing consoles and studio interfaces. IC Role / Device Role / Timing Role: Low-distortion analog switch element operating in linear region to gate signal paths without cross-conduction. Use Value: 1.6 pF Cre and 60 MHz fT preserve wideband audio fidelity; −50 nA IEBO prevents DC offset drift in precision op-amp feedback networks. |
| Industrial Sensor Biasing | High-Voltage Power Supply Sequencing |
Use Scenario: Providing stable bias current to high-impedance piezoelectric or ionization sensors in industrial monitoring systems. IC Role / Device Role / Timing Role: Constant-current source configured with emitter resistor, leveraging high VCEO and low ICBO for long-term stability. Use Value: −300 V rating allows direct connection to sensor excitation rails up to −200 V; hFE ≥50 ensures tight current regulation across temperature. | Use Scenario: Enabling/disabling auxiliary rails in multi-output HV SMPS controllers during startup and fault recovery sequences. IC Role / Device Role / Timing Role: High-side enable switch controlling gate drive or reference voltage to downstream regulators. Use Value: −800 mV VCE(sat) minimizes voltage drop and self-heating during sequencing; SOT23 footprint simplifies layout in space-constrained control sections. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PNP high-voltage transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BF820 | NPN complement; VCEO = +300 V, same package and gain profile | Requires inverted control logic and reversed supply polarity; not interchangeable without circuit redesign | Select when NPN topology is preferred for low-side switching or complementary pair design. |
| BC807-40 | Lower VCEO (−45 V), higher IC (−500 mA), same SOT23 package | Unsuitable for >−50 V applications; better for general-purpose switching but fails at telephony voltages | Choose only for cost-sensitive, low-voltage industrial controls where −300 V rating is unnecessary. |
Compared with BF820 and BC807-40, the BF821 uniquely satisfies −300 V line interface requirements while maintaining SOT23 manufacturability-neither alternative offers equivalent high-voltage PNP performance in this footprint.
Availability
BF821 is available at Aetrix Electronics and suitable for telephony line interface, professional audio switching, industrial sensor biasing, and high-voltage power supply sequencing requiring stable component supply and long-lifecycle availability.
Supply support for BF821 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
Nexperia is a global semiconductor expert focused on essential semiconductors, delivering high-performance, reliable discrete, logic, and MOSFET devices for automotive, industrial, and consumer markets.
The BF821 belongs to Nexperia's high-voltage bipolar transistor product line, engineered specifically for telecom infrastructure and professional equipment demanding robust off-state voltage blocking and low-leakage operation.
FAQ
Is BF821 automotive qualified?
No. The BF821 is explicitly designated as non-automotive qualified per Nexperia's revision history (v.4, October 2024). It is not tested to AEC-Q101 standards and lacks automotive-grade qualification documentation or screening. Use in automotive applications requires formal validation by the customer and carries no warranty from Nexperia or Aetrix Electronics.
What is the maximum allowable base current for continuous operation?
The absolute maximum peak base current (IBM) is −50 mA, but continuous operation must respect the total power dissipation limit of 250 mW at Tamb ≤ 25 °C. With VBE ≈ −0.85 V typical, sustained IB > −29 mA risks exceeding Ptot unless thermal management is enhanced beyond standard SOT23 mounting.
Can BF821 replace BF822 in a circuit?
No. BF822 is an NPN transistor with +300 V VCEO, making it electrically complementary-not functionally interchangeable-with the PNP BF821. Swapping them would invert switching polarity and likely cause circuit failure unless the entire bias network and signal path are redesigned.
Does BF821 have a built-in ESD protection diode?
No. The datasheet does not specify any integrated ESD protection structure. The device exhibits standard bipolar junction behavior with VEBO = −5 V and IEBO ≤ −50 nA at −5 V, indicating no internal clamp. External ESD protection must be implemented per IEC 61000-4-2 requirements in end-equipment design.
BF821,215 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- PNP
- Current - Collector (Ic) (Max):
- 50 mA
- Voltage - Collector Emitter Breakdown (Max):
- 300 V
- Vce Saturation (Max) @ Ib, Ic:
- 800mV @ 5mA, 30mA
- Current - Collector Cutoff (Max):
- 10nA (ICBO)
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 50 @ 25mA, 20V
- Power - Max:
- 250 mW
- Frequency - Transition:
- 60MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-236AB
BF821,215 FAQ
1.How can I place an order for BF821,215 through Aetrix?
Please submit a Request for Quotation (RFQ) for BF821,215 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 BF821,215 reliable?
The price and inventory of BF821,215 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BF821,215 is usually 5 days.
3.What payment methods are accepted for BF821,215?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BF821,215 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BF821,215?
BF821,215 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BF821,215 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 BF821,215?
For technical support, including BF821,215 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BF821,215 requirements.
6.How does Aetrix verify that BF821,215 is sourced from the original manufacturer or authorized distributors?
All BF821,215 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 BF821,215 meets industry standards.
7.What is the process for return or replacement of BF821,215?
All BF821,215 units undergo pre-shipment inspection (PSI). If there is an issue with BF821,215, 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 BF821,215 part is unused and in its original packaging.
Return procedure for BF821,215:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BF821,215 Tags
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