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Nexperia USA Inc. BZX84W-C18-QX
- Part No.:
- BZX84W-C18-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-C18-QX.pdf
- Description:
- DIODE ZENER 17.95V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:7,850
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Product details
Overview
BZX84W-C18-QX from Nexperia is a ±5% tolerance Zener diode with 18 V nominal regulation voltage, 225 Ω differential resistance at 5 mA, and 14.4 mV/K temperature coefficient, housed in an AEC-Q101-qualified SOT323 (SC-70) package for automotive voltage reference and overvoltage protection circuits.
For engineers reviewing the BZX84W-C18-QX datasheet, BZX84W-C18-QX pinout, BZX84W-C18-QX application, or BZX84W-C18-QX equivalent, this part delivers stable 18 V regulation in space-constrained automotive ECUs, power supply feedback loops, and ESD-clamped signal conditioning stages where low capacitance (1.5 pF) and high surge capability (70 A peak reverse current) are required.
Technical Context
This Zener diode operates in reverse breakdown to maintain a precise 18 V reference across its cathode-anode terminals under regulated current conditions (IZ = 5 mA). Its ±5% tolerance (C-series), 225 Ω dynamic impedance, and positive 14.4 mV/K temperature coefficient enable predictable drift compensation in analog sensing front-ends.
Designed for automotive-grade reliability, it meets AEC-Q101 stress testing requirements and supports operation from −55 °C to +150 °C ambient, with thermal resistance of 455 K/W on standard FR4 PCBs and non-repetitive surge handling up to 40 W for 100 µs pulses.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 16.8 V to 19.1 V at IZ = 5 mA - defines regulation band for 18 V nominal reference |
| Differential Resistance (rdif) | 225 Ω max at IZ = 5 mA - determines output voltage stability under load variation |
| Temperature Coefficient (SZ) | +14.4 mV/K at IZ = 5 mA - quantifies voltage drift per degree Celsius rise |
| Reverse Current (IR) | 50 nA max at VR = 12.6 V - ensures low leakage in standby or precision bias networks |
| Diode Capacitance (Cd) | 1.5 pF at f = 1 MHz, VR = 0 V - enables use in high-frequency filtering and RF decoupling |
| Total Power Dissipation (Ptot) | 275 mW at Tamb = 25 °C on FR4 - sets continuous DC power limit for thermal design |
| Non-repetitive Peak Reverse Current (IZSM) | 70 A at tp = 100 µs - supports transient overvoltage clamping without failure |
Pinout & Package
SOT323 (SC-70) leadless surface-mount plastic package with 3 terminals; compact 2.2 mm × 1.35 mm footprint and 0.65 mm pitch; optimized for reflow soldering per IPC-7351B.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward-biased terminal; connects to lower-potential node in regulation path |
| 2 | Not Connected (n.c.) | Internally isolated; must remain unconnected on PCB to avoid parasitic coupling |
| 3 | Cathode (K) | Reverse-biased terminal; connects to higher-potential node and regulates voltage at this node |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive under-hood and body-control module applications requiring extended temperature and reliability compliance |
| ±5% Zener voltage tolerance | Enables cost-effective selection for non-critical regulation where tighter tolerance is unnecessary |
| Low 1.5 pF junction capacitance | Minimizes signal distortion in high-speed analog interfaces and RF bypass paths |
| 70 A non-repetitive surge rating | Provides robust transient immunity in 12 V/24 V automotive power domains without external TVS stacking |
| 455 K/W junction-to-ambient thermal resistance | Supports thermal modeling on standard single-layer FR4 layouts without heatsinking |
Applications
| Automotive Body Control Module (BCM) | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Voltage reference for microcontroller ADC inputs monitoring battery voltage and lamp status in BCMs. IC Role / Device Role / Timing Role: Zener reference diode providing stable 18 V rail for precision divider networks feeding 3.3 V LDOs. Use Value: Maintains <±1% reference accuracy over −40 °C to +125 °C due to AEC-Q101 validation and known temperature coefficient. |
Use Scenario: Clamping and biasing of thermistor-based temperature sensor outputs before op-amp amplification. IC Role / Device Role / Timing Role: Precision shunt regulator establishing fixed bias point and limiting input swing to protect downstream amplifier inputs. Use Value: 1.5 pF capacitance avoids phase shift in 10 kHz sensor bandwidth; 225 Ω rdif ensures minimal loading error. |
| DC-DC Converter Feedback Network | ESD-Protected Interface Protection |
Use Scenario: Top resistor in voltage-divider feedback loop of isolated flyback converter regulating 18 V auxiliary rail. IC Role / Device Role / Timing Role: Zener element setting reference voltage for optocoupler-driven feedback path. Use Value: Tight 16.8–19.1 V range ensures consistent regulation despite input ripple; 275 mW Ptot accommodates worst-case divider current. |
Use Scenario: Secondary-stage clamping on CAN transceiver data lines subjected to ISO 10605 ESD events. IC Role / Device Role / Timing Role: Low-capacitance shunt clamp absorbing 8 kV contact discharge energy while preserving signal integrity. Use Value: 70 A IZSM handles full ESD pulse without degradation; 1.5 pF prevents data-rate degradation above 1 Mbps. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-B18-Q | ±2% tolerance (vs. ±5%), 175 Ω rdif, +14.4 mV/K SZ | Higher precision needed for reference-sensitive ADC buffers or low-drift op-amp biasing | Select when tighter voltage tolerance and lower dynamic impedance justify cost premium |
| MMSZ5245B-TP | ±5% tolerance, 18 V nominal, SOD-123 package, 220 Ω rdif, 200 mW Ptot | Lower power rating and larger footprint; not AEC-Q101 qualified | Acceptable for non-automotive consumer or industrial boards where qualification and surge margin are secondary |
Compared with BZX84W-C18-QX, the BZX84W-B18-Q offers tighter regulation but identical thermal and surge performance, while MMSZ5245B-TP trades AEC-Q101 compliance and 275 mW power handling for broader distributor availability in non-automotive contexts.
Availability
BZX84W-C18-QX is available at Aetrix Electronics and suitable for automotive electronics, industrial sensor systems, and power supply feedback networks requiring stable component supply with guaranteed long-term continuity.
Supply support for BZX84W-C18-QX 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-certified Zener diode product line, engineered specifically for robust voltage regulation and transient suppression in harsh automotive environments.
FAQ
What is the maximum continuous reverse current for reliable operation?
The BZX84W-C18-QX supports a maximum continuous reverse current of 60 mA at 25 °C ambient, derived from its 275 mW power rating and 18 V Zener voltage (IZ = Ptot/VZ). Derating is required above 25 °C per the 455 K/W thermal resistance specification.
Can this diode be used in parallel for higher power handling?
No-Zener diodes exhibit manufacturing spread in VZ and temperature coefficient, causing current imbalance and thermal runaway when paralleled. For higher power, use a single higher-rated device or implement active current-sharing circuitry.
Is the not-connected (n.c.) pin electrically isolated or internally tied?
Pin 2 is fully electrically isolated-no internal connection exists. It must remain unconnected on the PCB layout to prevent unintended coupling, capacitive loading, or mechanical stress on the die bond wire.
How does the 14.4 mV/K temperature coefficient affect regulation accuracy over temperature?
At 18 V nominal, a +14.4 mV/K coefficient yields +1.44 V drift over a 100 K rise (e.g., −40 °C to +60 °C), resulting in ~+8% relative change. This is factored into system-level calibration or compensated using complementary components in precision designs.
BZX84W-C18-QX 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):
- 17.95 V
- Tolerance:
- ±6.41%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 45 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 12.565 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-C18-QX FAQ
1.How can I place an order for BZX84W-C18-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-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 BZX84W-C18-QX reliable?
The price and inventory of BZX84W-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 BZX84W-C18-QX is usually 5 days.
3.What payment methods are accepted for BZX84W-C18-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-C18-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-C18-QX?
BZX84W-C18-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-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 BZX84W-C18-QX?
For technical support, including BZX84W-C18-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-C18-QX requirements.
6.How does Aetrix verify that BZX84W-C18-QX is sourced from the original manufacturer or authorized distributors?
All BZX84W-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 BZX84W-C18-QX meets industry standards.
7.What is the process for return or replacement of BZX84W-C18-QX?
All BZX84W-C18-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-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 BZX84W-C18-QX part is unused and in its original packaging.
Return procedure for BZX84W-C18-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-C18-QX Tags
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MMBZ5240B-7-F
Diodes Incorporated
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BZT52C5V6T-7
Diodes Incorporated
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MMSZ5231B-7-F
Diodes Incorporated
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BZT52C15-7-F
Diodes Incorporated
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BZX84C3V3LT1G
onsemi
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MMSZ5245BS-7-F
Diodes Incorporated
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MMSZ4682T1G
onsemi
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BZT52C15S-7-F
Diodes Incorporated
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MM5Z5V1ST1G
onsemi
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SMAJ4744A-TP
Micro Commercial Co
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BZT52C3V6LP-7
Diodes Incorporated
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SMAZ12-13-F
Diodes Incorporated
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