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Nexperia USA Inc. BZX384-B3V9-QX
- Part No.:
- BZX384-B3V9-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-76, SOD-323
- Datasheet:
-
BZX384-B3V9-QX.pdf
- Description:
- DIODE ZENER 3.9V 300MW SOD323
- Quantity:
- Payment:
- Shipping:
Inventory:6,558
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Product details
Overview
BZX384-B3V9-Q from Nexperia is a ±2 % tolerance Zener voltage regulator diode in SOD323 (SC-76) package, rated for 3.9 V nominal breakdown voltage at 5 mA, 300 mW total power dissipation, and qualified to AEC-Q101 for automotive voltage reference and overvoltage protection circuits.
For engineers reviewing the BZX384-B3V9-Q datasheet, BZX384-B3V9-Q pinout, BZX384-B3V9-Q application, or BZX384-B3V9-Q equivalent, this device serves as a precision low-power shunt regulator in ECU power rails, sensor biasing networks, and ADC reference stabilization where stable 3.9 V clamping with <3 Ω differential resistance and ≤3 μA reverse leakage at 1 V is required.
Technical Context
This Zener diode operates in reverse-biased breakdown mode to maintain a stable 3.9 V reference across its terminals under regulated current conditions (IZ = 5 mA). Its ±2 % tolerance ensures tight voltage control without trimming, and its 3 Ω typical differential resistance minimizes output variation under load changes.
Qualified per AEC-Q101, it supports junction temperatures from −65 °C to +150 °C and withstands non-repetitive 40 W surge pulses (tp = 100 μs), making it suitable for transient-prone automotive environments where thermal stability and surge resilience are critical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Breakdown Voltage (VZ) | 3.82 V to 3.98 V at IZ = 5 mA - defines precise clamping threshold for 3.9 V nominal regulation |
| Differential Resistance (rdif) | ≤90 Ω max at IZ = 5 mA - determines voltage deviation under dynamic current load |
| Reverse Current (IR) | ≤3 μA max at VR = 1 V - ensures minimal quiescent power loss in standby regulation |
| Total Power Dissipation (Ptot) | 300 mW at Tamb ≤ 25 °C - sets maximum continuous DC power handling on standard FR4 PCB |
| Non-repetitive Peak Power (PZSM) | 40 W for tp = 100 μs - enables robust transient suppression against ESD or load dump spikes |
| Junction Temperature (Tj) | −65 °C to +150 °C - supports operation in under-hood automotive environments |
| AEC-Q101 Qualified | Yes - certified for automotive-grade reliability including temperature cycling, HTRB, and ESD testing |
Pinout & Package
Package: SOD323 (SC-76), surface-mount plastic case with 2 leads, 1.35 mm × 0.85 mm footprint, cathode marked by bar on top surface.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Cathode (K) | Connected to regulated output node; reverse-biased terminal where voltage is referenced and clamped |
| 2 | Anode (A) | Connected to ground or lower-potential rail; completes current path during Zener conduction |
Key Features
| Feature | Design Value |
|---|---|
| ±2 % voltage tolerance | Enables accurate 3.9 V regulation without external calibration or trimming circuitry |
| 300 mW power rating | Supports continuous regulation in low-current bias networks (<77 mA at 3.9 V) on compact PCBs |
| 40 W surge capability | Withstands automotive load-dump transients and ISO 7637-2 pulse 1/2a without failure |
| AEC-Q101 qualification | Validates long-term reliability in automotive ECUs, body control modules, and ADAS sensors |
| SOD323 package | Enables high-density placement with 0.9 mm lead pitch and compatibility with standard reflow profiles |
Applications
| Automotive ECU Power Rail Clamping | Industrial Sensor Bias Reference |
|---|---|
|
Use Scenario: Stabilizing 3.9 V supply for microcontroller reset circuitry in engine control units exposed to battery transients. IC Role / Device Role / Timing Role: Shunt regulator providing precise voltage clamp to protect reset logic from overvoltage events. Use Value: Maintains reset assertion within 3.82–3.98 V window despite ±12 V battery swings, eliminating need for external voltage supervisor ICs. |
Use Scenario: Generating stable bias voltage for analog front-end amplifiers in pressure and temperature sensors. IC Role / Device Role / Timing Role: Low-noise Zener reference source ensuring consistent amplifier gain and offset calibration. Use Value: Delivers <3 μA reverse leakage and <90 Ω dynamic impedance, minimizing sensor output drift across −40 °C to +125 °C. |
| ADC Reference Stabilization | USB Port Overvoltage Protection |
|
Use Scenario: Providing fixed reference for 12-bit SAR ADCs in telematics modules requiring <0.5 LSB error budget. IC Role / Device Role / Timing Role: Precision voltage reference establishing ADC full-scale threshold independent of supply ripple. Use Value: Achieves ±0.078 V (2 %) reference accuracy and <0.02 % line regulation, meeting EN 50155 rail noise immunity requirements. |
Use Scenario: Clamping D+ and D− lines to 3.9 V in automotive USB-C receptacles subjected to hot-plug surges. IC Role / Device Role / Timing Role: Fast-response shunt protector limiting data-line voltage during ESD events per IEC 61000-4-2 Level 4. Use Value: Responds within nanoseconds to 8 kV contact discharge, limiting peak line voltage to ≤4.0 V while dissipating <40 W transient energy. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX384-B3V9 | No -Q suffix; not AEC-Q101 qualified; same electrical specs and SOD323 package | Not approved for automotive production; limited to industrial or consumer use | Select when AEC-Q101 compliance is unnecessary and cost sensitivity outweighs qualification requirements |
| MMSZ4684T1G | 3.9 V ±5 % tolerance; 500 mW Ptot; SOD-123 package; no AEC-Q101 certification | Higher power but looser tolerance and larger footprint; unsuitable for space-constrained automotive PCBs | Choose only if higher continuous power (500 mW) is needed and ±5 % regulation error is acceptable |
Compared with BZX384-B3V9-Q, the non-Q variant sacrifices automotive qualification for identical regulation performance, while MMSZ4684T1G trades tighter tolerance and smaller size for higher power and broader industrial acceptance-making the -Q version optimal for AEC-compliant 3.9 V reference designs demanding precision and miniaturization.
Availability
BZX384-B3V9-Q is available at Aetrix Electronics and suitable for automotive ECU design, industrial sensor signal conditioning, and USB interface protection requiring stable component supply with guaranteed AEC-Q101 compliance and traceable lot history.
Supply support for BZX384-B3V9-Q 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 delivering high-performance, reliable discrete, logic, and MOSFET devices with focus on efficiency, miniaturization, and automotive-grade quality.
The BZX384-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode portfolio, engineered specifically for precision voltage reference and transient protection in harsh automotive environments.
FAQ
What is the maximum continuous reverse current this diode can handle?
The BZX384-B3V9-Q is rated for a maximum forward current of 250 mA, but as a Zener regulator, its continuous reverse (Zener) current is limited by power dissipation. At 3.9 V, the absolute maximum continuous Zener current is 76.9 mA (300 mW ÷ 3.9 V), assuming ambient temperature ≤25 °C and adequate PCB copper area for thermal dissipation.
How does the ±2 % tolerance affect system-level voltage accuracy?
The ±2 % tolerance means the actual breakdown voltage falls between 3.82 V and 3.98 V at 5 mA. In practice, this translates to ±0.078 V absolute error at nominal current, which directly impacts reference stability in ADCs or reset thresholds-requiring system-level margin allocation but eliminating need for post-assembly calibration.
Can this diode replace older BZX384-B3V9 parts in existing designs?
Yes-BZX384-B3V9-Q is a direct drop-in replacement for BZX384-B3V9 in terms of pinout, electrical characteristics, and package. The only functional difference is AEC-Q101 qualification, which adds process controls and test coverage but does not alter electrical behavior or thermal performance on standard FR4 PCBs.
What is the thermal resistance from junction to solder point, and why does it matter?
Rth(j-sp) is 110 K/W, measured from junction to cathode solder point. This value is critical for estimating local junction temperature rise during pulsed operation: ΔTj = Ppulse × Rth(j-sp). For example, a 40 W 100 μs surge causes only ~4.4 °C rise at the cathode pad-enabling safe transient handling without bulk PCB heating.
BZX384-B3V9-QX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX384-Q
- Package/Case:
- SC-76, SOD-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 3.9 V
- Tolerance:
- ±2%
- Power - Max:
- 300 mW
- Impedance (Max) (Zzt):
- 90 Ohms
- Current - Reverse Leakage @ Vr:
- 3 µA @ 1 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.1 V @ 100 mA
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOD-323
BZX384-B3V9-QX FAQ
1.How can I place an order for BZX384-B3V9-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX384-B3V9-QX 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 BZX384-B3V9-QX reliable?
The price and inventory of BZX384-B3V9-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX384-B3V9-QX is usually 5 days.
3.What payment methods are accepted for BZX384-B3V9-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX384-B3V9-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX384-B3V9-QX?
BZX384-B3V9-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX384-B3V9-QX 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 BZX384-B3V9-QX?
For technical support, including BZX384-B3V9-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX384-B3V9-QX requirements.
6.How does Aetrix verify that BZX384-B3V9-QX is sourced from the original manufacturer or authorized distributors?
All BZX384-B3V9-QX 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 BZX384-B3V9-QX meets industry standards.
7.What is the process for return or replacement of BZX384-B3V9-QX?
All BZX384-B3V9-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX384-B3V9-QX, 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 BZX384-B3V9-QX part is unused and in its original packaging.
Return procedure for BZX384-B3V9-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX384-B3V9-QX Tags
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MM5Z5V1ST1G
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