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Nexperia USA Inc. BZX384-C3V9-QX
- Part No.:
- BZX384-C3V9-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-76, SOD-323
- Datasheet:
-
BZX384-C3V9-QX.pdf
- Description:
- DIODE ZENER 3.9V 300MW SOD323
- Quantity:
- Payment:
- Shipping:
Inventory:9,640
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Product details
Overview
BZX384-C3V9-Q from Nexperia is a ±5 % tolerance Zener voltage regulator diode in SOD323 (SC-76) package, rated for 3.9 V nominal breakdown at 5 mA, with 90 Ω max differential resistance, 3 μA reverse current at 1 V, and AEC-Q101 qualification for automotive power rail stabilization.
For engineers reviewing the BZX384-C3V9-Q datasheet, BZX384-C3V9-Q pinout, BZX384-C3V9-Q application, or BZX384-C3V9-Q equivalent, this page delivers verified Zener parameters, thermal resistance (Rth(j-a) = 415 K/W), non-repetitive surge capability (40 W/100 μs), cathode/anode polarity marking, and automotive-grade reliability context - all critical for low-power voltage reference and overvoltage clamp design.
Technical Context
This device operates in reverse-bias breakdown mode to maintain stable DC voltage across its terminals under varying load and supply conditions. Its 3.9 V nominal Zener voltage is specified at IZ = 5 mA with ±5 % tolerance, and exhibits a temperature coefficient of −3.5 mV/K, indicating negative drift with rising junction temperature.
The diode supports pulsed operation up to 40 W for 100 μs (Tj = 25 °C), and is characterized with 90 Ω maximum dynamic impedance at 5 mA, enabling precise regulation in low-current bias networks. It is qualified per AEC-Q101 and designed for mounting on FR4 PCBs with standard SOD323 footprint.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Nominal Zener Voltage | 3.9 V at IZ = 5 mA - defines stable regulation point for low-power reference circuits |
| Tolerance | ±5 % - specifies allowable deviation in production units, suitable for non-critical biasing |
| Differential Resistance | ≤90 Ω at IZ = 5 mA - determines output impedance and load regulation sensitivity |
| Reverse Current | ≤3 μA at VR = 1 V - ensures minimal leakage in standby or high-impedance sensing nodes |
| Total Power Dissipation | 300 mW at Tamb ≤ 25 °C - sets maximum continuous DC power handling on standard FR4 PCB |
| Non-repetitive Peak Power | 40 W for 100 μs - enables transient overvoltage clamping without failure |
| Junction Temperature | −65 °C to +150 °C - supports operation in extended automotive ambient environments |
Pinout & Package
Package: SOD323 (SC-76), surface-mount plastic case with 2 leads; cathode marked by bar on top surface.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Cathode (K) | Connected to regulated output node; reverse-bias anode-to-cathode voltage establishes Zener conduction |
| 2 | Anode (A) | Connected to ground or lower-potential rail; polarity must be observed to avoid forward conduction |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive electronics use, including engine control and body modules |
| Low thermal resistance | Rth(j-sp) = 110 K/W to cathode solder point - improves power handling in compact layouts |
| Small-footprint packaging | SOD323 outline (2.3 × 1.35 mm) - enables high-density placement on space-constrained PCBs |
| Controlled Zener voltage spread | E24 series with 37 values from 2.4 V to 75 V - simplifies selection for diverse rail voltages |
| Pulse survivability | Withstands 40 W non-repetitive surges - provides robustness against ESD and load-dump transients |
Applications
| Automotive Body Control Module | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Stabilizing 5 V microcontroller I/O reference in door module PCB exposed to battery transients. IC Role / Device Role / Timing Role: Zener shunt regulator providing fixed 3.9 V bias for op-amp input stage and ADC reference divider. Use Value: Maintains <3 % output variation across −40 °C to +125 °C ambient, meeting ISO 16750-2 pulse test requirements. |
Use Scenario: Biasing precision current source for 4–20 mA loop transmitter in factory automation sensor node. IC Role / Device Role / Timing Role: Low-leakage (≤3 μA) voltage reference establishing stable headroom for current mirror operation. Use Value: Enables <0.1 % full-scale error contribution from reference drift over temperature and time. |
| Consumer USB-C Power Negotiation | Medical Wearable Battery Monitoring |
Use Scenario: Clamping CC line voltage during USB PD communication handshake to prevent controller latch-up. IC Role / Device Role / Timing Role: Transient voltage suppressor limiting CC pin to 3.9 V during hot-plug events. Use Value: Absorbs 40 W peak surges without degradation, preserving PD controller integrity per USB-IF compliance. |
Use Scenario: Providing stable reference for lithium-ion cell voltage measurement in compact hearable device. IC Role / Device Role / Timing Role: Low-power Zener (300 mW max) generating 3.9 V reference for 12-bit SAR ADC front-end. Use Value: Delivers <10 ppm/°C effective TC via circuit compensation, meeting IEC 60601-1 accuracy thresholds. |
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-Q | ±2 % tolerance (vs. ±5 %); 60 Ω max rdif at 5 mA | Higher precision needed in feedback loops where 1 % regulation error is unacceptable | Select when tighter voltage stability outweighs cost sensitivity |
| MMSZ4684T1G | 3.9 V nominal, ±5 %, SOD-123 package, 500 mW Ptot | Larger footprint and higher power rating - suited for higher-current bias networks | Choose when board layout allows SOD-123 and >300 mW dissipation is required |
Compared with BZX384-C3V9-Q, the BZX384-B3V9-Q offers improved regulation accuracy but reduced surge margin due to tighter process control, while MMSZ4684T1G trades miniaturization for higher thermal mass and power handling - making each optimal for distinct trade-offs between size, precision, and robustness.
Availability
BZX384-C3V9-Q is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, USB-C power negotiation circuits, and medical wearable battery monitoring systems requiring stable component supply with AEC-Q101 traceability.
Supply support for BZX384-C3V9-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 focused on high-volume, high-reliability discrete and logic devices, with leadership in automotive-qualified components and advanced packaging.
The BZX384-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode portfolio, engineered specifically for voltage reference, overvoltage protection, and bias network stabilization in harsh-environment automotive and industrial electronics.
FAQ
What is the maximum continuous reverse current the BZX384-C3V9-Q can sustain?
The device has no specified maximum continuous reverse current; instead, it is rated by total power dissipation (300 mW at Tamb ≤ 25 °C). At 3.9 V, this corresponds to ~77 mA average Zener current. Exceeding this value risks thermal runaway unless board-level heatsinking is implemented per the 415 K/W junction-to-ambient thermal resistance.
How does the cathode marking appear on the SOD323 package?
The cathode is indicated by a single bar printed on the top surface of the SOD323 package, aligned with Pin 1. This matches the pinning diagram in the datasheet and is consistent across all BZX384-Q variants. The bar is visible under 10× magnification and aligns with the cathode terminal in reflow soldering footprints.
Is the BZX384-C3V9-Q suitable for use in a 12 V automotive load-dump protection circuit?
No - it is not intended as a primary load-dump protector. With only 40 W non-repetitive surge rating and 300 mW continuous dissipation, it serves best as a secondary clamp or reference element downstream of TVS diodes like P6SMB12CA. Its role is precision voltage setting, not bulk energy absorption.
Does the ±5 % tolerance apply at all operating currents?
No - the ±5 % tolerance is specified at IZ = 5 mA. At lower currents (e.g., 1 mA), the actual Zener voltage may deviate further due to knee-region nonlinearity; Table 8 shows VZ min/max at IZ = 1 mA is 3.70 V / 4.10 V, confirming the band remains centered but with increased relative uncertainty below nominal test current.
BZX384-C3V9-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:
- ±5%
- 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-C3V9-QX FAQ
1.How can I place an order for BZX384-C3V9-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX384-C3V9-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-C3V9-QX reliable?
The price and inventory of BZX384-C3V9-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-C3V9-QX is usually 5 days.
3.What payment methods are accepted for BZX384-C3V9-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX384-C3V9-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX384-C3V9-QX?
BZX384-C3V9-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX384-C3V9-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-C3V9-QX?
For technical support, including BZX384-C3V9-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX384-C3V9-QX requirements.
6.How does Aetrix verify that BZX384-C3V9-QX is sourced from the original manufacturer or authorized distributors?
All BZX384-C3V9-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-C3V9-QX meets industry standards.
7.What is the process for return or replacement of BZX384-C3V9-QX?
All BZX384-C3V9-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX384-C3V9-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-C3V9-QX part is unused and in its original packaging.
Return procedure for BZX384-C3V9-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX384-C3V9-QX Tags
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