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Nexperia USA Inc. BZX384-C18-QX
- Part No.:
- BZX384-C18-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-76, SOD-323
- Datasheet:
-
BZX384-C18-QX.pdf
- Description:
- DIODE ZENER 17.95V 300MW SOD323
- Quantity:
- Payment:
- Shipping:
Inventory:5,015
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Product details
Overview
BZX384-C18-Q from Nexperia is a ±5 % tolerance Zener voltage regulator diode in SOD323 (SC-76) package, rated for 18 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-C18-Q datasheet, BZX384-C18-Q pinout, BZX384-C18-Q application, or BZX384-C18-Q equivalent, key selection criteria include its 16.8–19.1 V Zener voltage range, 225 Ω max differential resistance at 5 mA, 45 μA max reverse current at 14.4 V, -0.05 mV/K temperature coefficient, and 70 pF capacitance at 0 V - critical for precision biasing and low-noise regulation in space-constrained designs.
Technical Context
This device operates as a two-terminal shunt voltage reference, maintaining stable output by conducting reverse current above its specified Zener voltage. It exhibits a negative temperature coefficient of -0.05 mV/K at IZ = 5 mA, ensuring predictable drift across automotive ambient ranges (-65 °C to +150 °C).
Designed for low-power regulation, it supports continuous DC operation up to 300 mW at Tamb ≤ 25 °C and withstands non-repetitive 100 μs surges up to 40 W (IZSM = 1.5 A), with thermal resistance from junction to solder point at 110 K/W for reliable PCB-level thermal management.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 16.8 V to 19.1 V at IZ = 5 mA - defines usable regulation window under standard test conditions |
| Differential Resistance (rdif) | ≤225 Ω at IZ = 5 mA - determines regulation stiffness and output impedance in feedback paths |
| Reverse Current (IR) | ≤45 μA at VR = 14.4 V - ensures low leakage before knee conduction, critical for standby power integrity |
| Power Dissipation (Ptot) | 300 mW at Tamb ≤ 25 °C on FR4 PCB - sets maximum continuous DC load capability without derating |
| Non-repetitive Peak Power (PZSM) | 40 W for tp = 100 μs - enables transient overvoltage clamping in ESD/surge events |
| Junction Temperature (Tj) | 150 °C maximum - defines upper thermal limit for sustained operation in automotive under-hood environments |
| Package | SOD323 (SC-76) - 2.7 × 1.6 mm surface-mount footprint enabling high-density layout in compact modules |
Pinout & Package
SOD323 (SC-76) plastic surface-mounted package with cathode-marked top-side bar; 2-terminal configuration optimized for automated placement and reflow soldering per IPC-7351B footprint standards.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Cathode (K) | Connected to regulated output node; marking bar identifies this terminal for polarity-critical placement |
| 2 | Anode (A) | Connected to ground or lower-potential rail; completes shunt path for Zener conduction |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive-grade reliability including temperature cycling, HTRB, and ESD testing per JESD22-A114 |
| ±5 % Zener tolerance (C-series) | Cost-optimized voltage accuracy for non-critical biasing and clamping where tight regulation is not required |
| Low 70 pF capacitance at 0 V | Minimizes signal distortion in high-frequency applications such as RF detector biasing or clock line stabilization |
| 110 K/W junction-to-solder-point Rth | Enables effective heat transfer to PCB copper, supporting stable operation at 250 mA peak forward current |
| 150 °C max junction temperature | Permits deployment in engine control units, body electronics, and ADAS modules without external heatsinking |
Applications
| Automotive Body Control Module (BCM) | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Providing stable 18 V reference for microcontroller ADC input scaling in door module voltage monitoring. IC Role / Device Role / Timing Role: Shunt voltage reference establishing precise analog input range for 12-bit ADC conversion. Use Value: Maintains ±1.5 % full-scale accuracy over -40 °C to +125 °C ambient due to low tempco and AEC-Q101 thermal robustness. |
Use Scenario: Biasing op-amp inputs in 4–20 mA transmitter front-end circuits operating from 24 V loop supply. IC Role / Device Role / Timing Role: Low-leakage Zener clamp protecting amplifier rails during field-wiring transients. Use Value: Limits rail excursion to ≤19.1 V with <45 μA IR at 14.4 V, preventing op-amp saturation and preserving loop integrity. |
| Consumer Power Adapter Feedback | Medical Portable Device Voltage Monitoring |
Use Scenario: Secondary-side voltage sensing in isolated flyback converters for USB-C PD adapters. IC Role / Device Role / Timing Role: Precision reference for optocoupler feedback network regulating 18 V auxiliary output. Use Value: Delivers stable 18 V setpoint with 225 Ω rdif, minimizing load-regulation error across 10–100 % output loading. |
Use Scenario: Battery voltage threshold detection in portable ultrasound handsets using single-cell Li-ion packs. IC Role / Device Role / Timing Role: Overvoltage protector triggering shutdown when cell voltage exceeds safe charging limit. Use Value: Clamps at 19.1 V with 40 W surge capability, safeguarding analog front-end ICs during fast-charge termination overshoot. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX384-B18-Q | ±2 % tolerance (17.6–18.4 V), 12.6 mV/K tempco, 200 Ω rdif | Higher accuracy and tighter tempco for precision references; higher cost | Select when regulation stability over temperature is prioritized over cost |
| MMSZ4685T1G | ±5 % (17.1–18.9 V), 500 mW Ptot, SOD-123 package, 300 Ω rdif | Larger footprint, higher power rating, but higher dynamic impedance | Choose for legacy board compatibility or where 500 mW headroom justifies larger size |
Compared with BZX384-C18-Q, the BZX384-B18-Q offers superior voltage stability at higher cost, while MMSZ4685T1G trades smaller SOD323 size for greater power handling and relaxed regulation performance - making the C-series optimal for cost-sensitive, space-constrained automotive and industrial biasing.
Availability
BZX384-C18-Q is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, consumer power adapter feedback loops, and medical portable device voltage monitoring requiring stable component supply with AEC-Q101 compliance.
Supply support for BZX384-C18-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 energy-efficient solutions.
The BZX384-Q series belongs to Nexperia's automotive-grade Zener diode product line, engineered specifically for robust voltage reference and overvoltage protection in harsh-environment electronic control units.
FAQ
What is the maximum continuous reverse current the BZX384-C18-Q can sustain?
The device does not specify a maximum continuous reverse current rating; instead, it is limited by total power dissipation. At 18 V Zener voltage, the maximum sustainable DC reverse current is 16.7 mA (300 mW ÷ 18 V), assuming Tamb ≤ 25 °C and proper PCB thermal design per datasheet mounting conditions.
Can BZX384-C18-Q be used in parallel for higher power handling?
No - Zener diodes exhibit negative temperature coefficients and manufacturing spread, causing current imbalance when paralleled. This leads to thermal runaway in one device. For higher power, use a single higher-rated Zener or implement active regulation instead.
How does the ±5 % tolerance affect circuit performance in a 12 V system with 18 V clamp?
In a 12 V system, the 18 V clamp operates well above normal rail voltage, so the ±5 % tolerance (16.8–19.1 V) ensures consistent overvoltage protection without false triggering. The wide range accommodates process variation while maintaining safety margin against 16 V transients common in automotive load-dump scenarios.
Is the SOD323 package compatible with standard reflow profiles for lead-free soldering?
Yes - Nexperia specifies compatibility with JEDEC J-STD-020D reflow profiles. The SOD323 outline supports peak temperatures up to 260 °C for ≤30 seconds, with recommended solder land dimensions of 0.5 × 1.1 mm per pad and 0.6 mm solder resist opening, as detailed in Figure 12 of the datasheet.
BZX384-C18-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):
- 17.95 V
- Tolerance:
- ±5%
- Power - Max:
- 300 mW
- Impedance (Max) (Zzt):
- 45 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 12.565 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-C18-QX FAQ
1.How can I place an order for BZX384-C18-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX384-C18-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-C18-QX reliable?
The price and inventory of BZX384-C18-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-C18-QX is usually 5 days.
3.What payment methods are accepted for BZX384-C18-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX384-C18-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX384-C18-QX?
BZX384-C18-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX384-C18-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-C18-QX?
For technical support, including BZX384-C18-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX384-C18-QX requirements.
6.How does Aetrix verify that BZX384-C18-QX is sourced from the original manufacturer or authorized distributors?
All BZX384-C18-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-C18-QX meets industry standards.
7.What is the process for return or replacement of BZX384-C18-QX?
All BZX384-C18-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX384-C18-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-C18-QX part is unused and in its original packaging.
Return procedure for BZX384-C18-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX384-C18-QX Tags
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MM5Z5V1ST1G
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