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Nexperia USA Inc. BZX84W-B3V9-QF
- Part No.:
- BZX84W-B3V9-QF
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B3V9-QF.pdf
- Description:
- DIODE ZENER 3.9V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:4,697
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Product details
Overview
BZX84W-B3V9-QF from Nexperia is a ±2 % tolerance Zener diode in SOT323 (SC-70) package, rated for 3.9 V nominal regulation voltage at 5 mA, with 275 mW total power dissipation and 3 µA reverse current at VR = 1 V, used for precision voltage reference and overvoltage protection in automotive power rails.
For engineers reviewing the BZX84W-B3V9-QF datasheet, BZX84W-B3V9-QF pinout, BZX84W-B3V9-QF application, or BZX84W-B3V9-QF equivalent, this page delivers verified Zener voltage, thermal resistance, differential resistance, temperature coefficient, and AEC-Q101 qualification status - critical for automotive-grade voltage clamping and biasing designs.
Technical Context
This Zener diode operates in reverse breakdown mode to maintain stable 3.9 V across its terminals under regulated current conditions. Its ±2 % tolerance ensures tight voltage control, and its negative temperature coefficient of −2.5 mV/K (at IZ = 5 mA) enables predictable drift behavior in temperature-varying environments.
The device features low differential resistance (90 Ω at IZ = 5 mA), enabling minimal output voltage variation under load changes, and supports non-repetitive surge handling up to 40 W for tp = 100 µs, making it suitable for transient suppression in compact automotive modules.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 3.9 V nominal at IZ = 5 mA; defines precise regulation point for reference or clamp circuits |
| Tolerance | ±2 % (B-series); ensures voltage accuracy within ±0.078 V for high-stability biasing |
| Differential Resistance (rdif) | 90 Ω max at IZ = 5 mA; limits output voltage shift under dynamic current load |
| Reverse Current (IR) | 3 µA max at VR = 1 V; guarantees low leakage in standby or high-impedance sensing nodes |
| Total Power Dissipation (Ptot) | 275 mW at Tamb = 25 °C on FR4 PCB; sets continuous thermal limit for board-level layout |
| Thermal Resistance (Rth(j-a)) | 455 K/W; determines junction-to-ambient temperature rise per watt under standard mounting |
| Temperature Coefficient (SZ) | −2.5 mV/K at IZ = 5 mA; quantifies voltage drift with temperature for compensation design |
Pinout & Package
SOT323 (SC-70) leadless surface-mount plastic package with 3 terminals; dimensions: 2.2 mm × 1.35 mm × 0.95 mm (L × W × H), 0.65 mm pitch.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward-biased terminal; connects to lower-potential node in Zener operation (reverse-biased configuration) |
| 2 | Not Connected (n.c.) | Internally unconnected; must remain floating - no PCB trace or solder joint required |
| 3 | Cathode (K) | Reverse-biased terminal; connects to higher-potential node to enable Zener conduction and voltage regulation |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive applications including engine control units and body electronics |
| Low capacitance (6 pF) | Minimizes signal distortion in high-frequency regulation and RF-coupled protection paths |
| Wide working voltage range (2.4–75 V) | Enables single-family sourcing across multiple voltage rails without redesigning footprint |
| Standard SOT323 footprint | Ensures compatibility with automated placement and reflow processes in high-volume manufacturing |
| Pulse surge capability (40 W) | Supports transient immunity per ISO 7637-2 without external TVS augmentation |
Applications
| Automotive Engine Control Unit (ECU) Reference | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Providing stable 3.9 V reference for analog-to-digital converter (ADC) biasing in engine coolant temperature sensor interface. IC Role / Device Role / Timing Role: Zener voltage reference establishing precise input scaling for 12-bit ADC conversion. Use Value: ±2 % tolerance and −2.5 mV/K TC ensure <±0.5 % full-scale error over −40 °C to +125 °C operating range. |
Use Scenario: Clamping amplifier input stage against ESD and load dump transients in 4–20 mA loop-powered pressure transmitters. IC Role / Device Role / Timing Role: Reverse-biased Zener acting as shunt overvoltage protector at op-amp input node. Use Value: 40 W non-repetitive peak power rating absorbs 100 µs surges without degradation, preserving signal integrity. |
| Automotive Infotainment Power Sequencing | Medical Portable Device Bias Network |
Use Scenario: Generating clean 3.9 V auxiliary supply for microcontroller reset circuitry during cold-crank battery conditions (6–16 V). IC Role / Device Role / Timing Role: Shunt regulator maintaining defined threshold for POR (Power-On Reset) logic activation. Use Value: 275 mW Ptot and 455 K/W Rth(j-a) allow reliable operation at 105 °C ambient without derating. |
Use Scenario: Establishing low-power bias voltage for photodiode transimpedance amplifier in battery-operated pulse oximeter front-end. IC Role / Device Role / Timing Role: Low-leakage (3 µA at 1 V) Zener providing stable reference while minimizing quiescent current draw. Use Value: 3 µA reverse current at VR = 1 V reduces standby power loss by >90 % versus generic 5.1 V Zeners in same package. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-C3V9-Q | ±5 % tolerance (vs. ±2 %); identical package, VZ, Ptot, and thermal specs | Acceptable where cost sensitivity outweighs voltage accuracy requirements | Select when ±0.2 V regulation window suffices and AEC-Q101 compliance remains mandatory |
| MMSZ4685T1G | ±5 % tolerance; SOD-123 package (larger footprint); 500 mW Ptot; not AEC-Q101 qualified | Suitable for industrial but not automotive use; higher power margin at expense of board area | Choose only for non-automotive designs requiring higher continuous dissipation and relaxed qualification |
Compared with BZX84W-B3V9-QF, the C3V9-Q offers cost advantage with looser tolerance, while MMSZ4685T1G trades automotive qualification and miniaturization for higher power handling - selection depends strictly on whether AEC-Q101, ±2 %, and SOT323 are mandatory system constraints.
Availability
BZX84W-B3V9-QF is available at Aetrix Electronics and suitable for automotive ECU reference, industrial sensor conditioning, and medical portable device bias networks requiring stable component supply, AEC-Q101 validation, and SOT323 footprint consistency.
Supply support for BZX84W-B3V9-QF 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 high-volume, high-reliability discrete and logic devices, with leadership in automotive-qualified components and advanced packaging.
The BZX84W-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode product line, engineered specifically for robust voltage regulation and clamping in harsh automotive and industrial environments.
FAQ
What is the maximum continuous Zener current for BZX84W-B3V9-QF at 85 °C ambient?
At Tamb = 85 °C, derating applies per thermal resistance: ΔT = 85 − 25 = 60 K; allowable power = 60 K ÷ 455 K/W ≈ 132 mW; thus IZ(max) ≈ 132 mW ÷ 3.9 V ≈ 33.8 mA. This assumes FR4 PCB mounting with single-sided copper and standard footprint as specified in the datasheet.
Does pin 2 require grounding or can it be left unconnected?
Pin 2 is explicitly marked "n.c." (not connected) in the official Nexperia datasheet and internal die construction. It must remain electrically floating - no PCB trace, solder mask opening, or thermal pad connection is permitted, as it is not bonded to any internal structure.
How does the −2.5 mV/K temperature coefficient affect regulation accuracy over −40 °C to +125 °C?
Over that 165 K range, total drift = −2.5 mV/K × 165 K = −412.5 mV. With nominal VZ = 3.9 V, this yields −10.6 % deviation. However, actual drift is nonlinear and mitigated by the ±2 % initial tolerance band; worst-case combined error remains within ±12.6 % across full temperature range.
Is BZX84W-B3V9-QF compatible with lead-free reflow profiles per JEDEC J-STD-020?
Yes - Nexperia specifies full compatibility with standard lead-free reflow profiles (peak 260 °C, 20–40 sec above 217 °C). The SOT323 package outline and material set meet JEDEC J-STD-020D requirements, and the device is qualified for IPC-A-610 Class 2/3 assembly standards.
BZX84W-B3V9-QF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX84W-Q
- Package/Case:
- SC-70, SOT-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 3.9 V
- Tolerance:
- ±2.05%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 90 Ohms
- Current - Reverse Leakage @ Vr:
- 3 µA @ 1 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
BZX84W-B3V9-QF FAQ
1.How can I place an order for BZX84W-B3V9-QF through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B3V9-QF 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 BZX84W-B3V9-QF reliable?
The price and inventory of BZX84W-B3V9-QF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX84W-B3V9-QF is usually 5 days.
3.What payment methods are accepted for BZX84W-B3V9-QF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B3V9-QF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B3V9-QF?
BZX84W-B3V9-QF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B3V9-QF 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 BZX84W-B3V9-QF?
For technical support, including BZX84W-B3V9-QF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B3V9-QF requirements.
6.How does Aetrix verify that BZX84W-B3V9-QF is sourced from the original manufacturer or authorized distributors?
All BZX84W-B3V9-QF 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 BZX84W-B3V9-QF meets industry standards.
7.What is the process for return or replacement of BZX84W-B3V9-QF?
All BZX84W-B3V9-QF units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B3V9-QF, 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 BZX84W-B3V9-QF part is unused and in its original packaging.
Return procedure for BZX84W-B3V9-QF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B3V9-QF Tags
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BZT52C5V6T-7
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MMSZ5231B-7-F
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BZX84C3V3LT1G
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MMSZ4682T1G
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MM5Z5V1ST1G
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