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Nexperia USA Inc. BZX84W-B43-QX
- Part No.:
- BZX84W-B43-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B43-QX.pdf
- Description:
- DIODE ZENER 43V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:6,115
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Product details
Overview
BZX84W-B43-QX from Nexperia is a ±2 % tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 43 V nominal Zener voltage at 5 mA, 275 mW total power dissipation, and qualified to AEC-Q101 for automotive use. It provides stable voltage reference in low-power biasing, overvoltage protection, and signal conditioning circuits.
For engineers reviewing the BZX84W-B43-QX datasheet, BZX84W-B43-QX pinout, BZX84W-B43-QX application, or BZX84W-B43-QX equivalent, key selection factors include its 43 V Zener voltage with ±2 % tolerance, 375 Ω typical differential resistance at 2 mA, −41.2 mV/K temperature coefficient, and automotive-grade reliability in ultra-small SOT323 packaging.
Technical Context
This Zener diode operates in reverse breakdown mode to maintain a stable reference voltage across its cathode–anode terminals under controlled current conditions. Its 43 V nominal Zener voltage is specified at IZ = 2 mA, with a maximum differential resistance of 375 Ω and non-repetitive peak reverse power dissipation up to 40 W for 100 µs pulses.
The device exhibits a negative temperature coefficient of −41.2 mV/K at IZ = 2 mA, indicating decreasing Zener voltage with rising junction temperature. It is mounted on FR4 PCB with single-sided copper and standard SOT323 footprint, yielding a thermal resistance of 455 K/W from junction to ambient.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 42.1 V to 43.9 V at IZ = 2 mA - defines precise regulation point for feedback or clamping |
| Tolerance | ±2 % - ensures tight voltage accuracy critical for automotive sensor biasing and reference stability |
| Differential Resistance (rdiff) | Max 375 Ω at IZ = 2 mA - determines output impedance and load regulation sensitivity |
| Power Dissipation (Ptot) | 275 mW at Tamb = 25 °C - sets maximum continuous DC power handling on standard FR4 PCB |
| Reverse Current (IR) | 50 nA at VR = 0.7 × VZnom - confirms low leakage for high-impedance sensing nodes |
| Thermal Resistance (Rth(j-a)) | 455 K/W - quantifies self-heating impact under sustained bias; limits usable current at elevated ambient |
| Temperature Coefficient (SZ) | −41.2 mV/K at IZ = 2 mA - enables compensation design in temperature-critical voltage references |
Pinout & Package
Package: SOT323 (SC-70), leadless surface-mount plastic package with 3 terminals, 1.3 mm × 1.8 mm body size, 0.65 mm pitch.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward-biased terminal; connected to lower potential side in Zener regulation configuration |
| 2 | Not Connected (n.c.) | Internally unconnected; must remain floating-no PCB trace or solder joint required |
| 3 | Cathode (K) | Reverse-biased terminal; connected to higher potential side and current-limiting resistor in shunt regulator |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive applications including engine control units and ADAS sensor modules |
| Ultra-small SOT323 package | Enables high-density PCB layouts in space-constrained modules like body controllers and infotainment power rails |
| 43 V ±2 % Zener voltage | Supports precise 42–44 V clamping in 36 V automotive systems and industrial 48 V DC supply monitoring |
| Low leakage current | 50 nA max at 0.7×VZ preserves accuracy in high-impedance voltage divider networks |
| High surge capability | 40 W non-repetitive peak reverse power (100 µs pulse) protects against transient overvoltage events |
Applications
| Automotive Sensor Biasing | Industrial Power Rail Clamping |
|---|---|
|
Use Scenario: Providing stable bias voltage to analog pressure or temperature sensors in engine control modules. IC Role / Device Role / Timing Role: Shunt Zener reference regulating sensor excitation voltage against battery fluctuations. Use Value: Maintains ±2 % reference accuracy across −40 °C to +125 °C ambient, ensuring sensor linearity compliance per ISO 16750-2. |
Use Scenario: Clamping 48 V DC bus transients in factory automation PLC I/O modules. IC Role / Device Role / Timing Role: Low-leakage shunt protector absorbing short-duration surges without latch-up. Use Value: Withstands 40 W non-repetitive pulses while limiting rail voltage to ≤44 V, protecting downstream ADCs and isolators. |
| Portable Medical Device Reference | Telecom Line Interface Protection |
|
Use Scenario: Generating precision 43 V reference for high-voltage op-amp biasing in portable ultrasound front-ends. IC Role / Device Role / Timing Role: Low-noise voltage reference element in analog signal chain power domain. Use Value: −41.2 mV/K temperature coefficient allows predictable drift compensation in closed-loop calibration routines. |
Use Scenario: Protecting RS-485 transceiver inputs from induced lightning surges on outdoor cabling. IC Role / Device Role / Timing Role: Fast-response overvoltage clamp placed before TVS diode array for staged protection. Use Value: 375 Ω differential resistance ensures minimal loading on data lines during normal operation while enabling rapid clamping onset. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-C43-Q | ±5 % tolerance (40–46 V range) vs. ±2 % (42.1–43.9 V); identical package, power rating, and thermal specs | Suitable where cost sensitivity outweighs tight voltage accuracy; less suitable for sensor bias requiring <1 % error budget | Select when system-level calibration compensates for wider VZ spread and AEC-Q101 compliance remains mandatory |
| MMSZ43ET1G | ±5 % tolerance; SOD-123 package (larger footprint); 500 mW Ptot; not AEC-Q101 qualified | Acceptable for commercial-grade 48 V rail clamping but excluded from automotive ECU designs | Choose only for non-automotive applications needing higher power margin and no automotive qualification requirement |
Compared with BZX84W-B43-QX, the BZX84W-C43-Q offers lower cost at the expense of voltage accuracy, while MMSZ43ET1G trades automotive qualification and compactness for higher power handling-making the BZX84W-B43-QX optimal for space-constrained, safety-critical automotive voltage references.
Availability
BZX84W-B43-QX is available at Aetrix Electronics and suitable for automotive electronics, industrial power monitoring, and medical instrumentation requiring stable component supply, AEC-Q101 compliance, and ultra-small SMT packaging.
Supply support for BZX84W-B43-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 technologies.
The BZX84W-Q series belongs to Nexperia's automotive-grade Zener diode product line, engineered specifically for robust voltage regulation and transient suppression in harsh-environment electronic control units.
FAQ
What is the maximum continuous reverse current for reliable long-term operation?
The BZX84W-B43-QX supports a maximum continuous reverse current of 200 mA, derived from its 275 mW power rating and 43 V Zener voltage (P = V × I). Operation above this current risks exceeding thermal limits on standard FR4 PCBs, especially above 70 °C ambient.
How does the n.c. pin affect PCB layout and thermal performance?
Pin 2 is internally not connected and must remain un-soldered and un-traced on the PCB. Leaving it floating avoids parasitic coupling and maintains the specified 455 K/W thermal resistance; connecting it would disrupt thermal path integrity and increase junction temperature under load.
Can this Zener diode be used in series or parallel configurations?
Series connection is permissible for higher voltage references but requires matched units to avoid current imbalance; parallel use is strongly discouraged due to mismatched Zener voltages causing current hogging and thermal runaway. Single-device shunt regulation is the validated configuration.
Is the −41.2 mV/K temperature coefficient linear across the full operating range?
No-the temperature coefficient varies with Zener voltage and test current; for BZX84W-B43-QX, −41.2 mV/K is typical at IZ = 2 mA and 25 °C. The coefficient becomes less negative above 100 °C and shows curvature in Fig. 6–7 of the datasheet, requiring system-level characterization for precision applications.
BZX84W-B43-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):
- 43 V
- Tolerance:
- ±2.09%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 150 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 30.1 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-B43-QX FAQ
1.How can I place an order for BZX84W-B43-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B43-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-B43-QX reliable?
The price and inventory of BZX84W-B43-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-B43-QX is usually 5 days.
3.What payment methods are accepted for BZX84W-B43-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B43-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B43-QX?
BZX84W-B43-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B43-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-B43-QX?
For technical support, including BZX84W-B43-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B43-QX requirements.
6.How does Aetrix verify that BZX84W-B43-QX is sourced from the original manufacturer or authorized distributors?
All BZX84W-B43-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-B43-QX meets industry standards.
7.What is the process for return or replacement of BZX84W-B43-QX?
All BZX84W-B43-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B43-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-B43-QX part is unused and in its original packaging.
Return procedure for BZX84W-B43-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B43-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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