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Nexperia USA Inc. BZX84W-B33-QX
- Part No.:
- BZX84W-B33-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B33-QX.pdf
- Description:
- DIODE ZENER 33V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:8,621
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Product details
Overview
BZX84W-B33-QX from Nexperia is a ±2 % tolerance Zener voltage regulator diode in SOT323 (SC-70) package, rated for 33 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 power supply rails, overvoltage protection circuits, and precision biasing networks.
For engineers reviewing the BZX84W-B33-QX datasheet, BZX84W-B33-QX pinout, BZX84W-B33-QX application, or BZX84W-B33-QX equivalent, key selection criteria include Zener voltage tolerance (±2 %), thermal resistance (455 K/W), reverse leakage current (50 nA at 23.1 V), differential resistance (325 Ω at 5 mA), and automotive qualification status.
Technical Context
This Zener diode operates in reverse breakdown mode with a specified 33 V nominal Zener voltage at IZ = 5 mA and exhibits a positive temperature coefficient of +29.7 mV/K. Its differential resistance of 325 Ω at 5 mA defines regulation stiffness under dynamic load changes.
The device features a non-connected (n.c.) terminal (Pin 2), enabling layout flexibility in high-density PCB designs while maintaining anode–cathode isolation. Thermal performance is characterized by Rth(j-a) = 455 K/W on FR4 with single-sided copper, limiting continuous power handling at elevated ambient temperatures.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 33 V nominal at IZ = 5 mA; tight ±2 % tolerance ensures predictable clamping level in reference circuits. |
| Power Dissipation (Ptot) | 275 mW at Tamb = 25 °C; defines maximum steady-state heat generation on standard FR4 PCB. |
| Differential Resistance (rdif) | 325 Ω at IZ = 5 mA; quantifies voltage change per mA shift in Zener current-critical for regulation accuracy. |
| Reverse Leakage (IR) | 50 nA at VR = 23.1 V (0.7 × VZ); low leakage preserves efficiency in high-impedance bias networks. |
| Forward Voltage (VF) | 0.9 V at IF = 10 mA; enables use as forward-biased clamp or ESD protection element in dual-role designs. |
| Junction Temperature (Tj) | 150 °C maximum; supports operation in under-hood automotive environments with proper thermal management. |
| Package | SOT323 (SC-70); 1.3 mm × 1.8 mm footprint with 0.65 mm pitch-suitable for space-constrained automotive ECUs. |
Pinout & Package
SOT323 (SC-70) surface-mount plastic package with leadless terminations, 1.3 mm × 1.8 mm body, 0.65 mm pin pitch, and 0.45 mm max height. Designed for reflow soldering with defined footprint per Figure 9.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward current entry point; connected to lower-potential node in Zener regulation configuration. |
| 2 | Not Connected (n.c.) | Internally unconnected; electrically isolated-no routing or grounding required. |
| 3 | Cathode (K) | Reverse-bias terminal; tied to higher-potential rail to enable Zener breakdown conduction. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive applications including engine control units and ADAS power domains. |
| ±2 % Zener voltage tolerance | Enables tighter output voltage control than ±5 % variants-reducing need for post-regulation trimming. |
| Low reverse leakage (50 nA) | Minimizes quiescent current draw in battery-backed systems and high-impedance sensing nodes. |
| 325 Ω differential resistance | Provides stable regulation under ±1 mA load variation-suitable for analog reference buffering. |
| SOT323 package | Enables automated placement and reflow compatibility while occupying <1.5 mm² PCB area. |
Applications
| Automotive Engine Control Unit (ECU) Reference | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Providing stable 33 V reference for microcontroller ADC biasing and analog front-end calibration in under-hood ECUs. IC Role / Device Role / Timing Role: Zener voltage reference diode operating in reverse breakdown to fix reference potential against supply ripple and thermal drift. Use Value: ±2 % tolerance and AEC-Q101 qualification ensure long-term stability across −40 °C to +125 °C ambient, reducing calibration frequency. |
Use Scenario: Clamping amplifier input stages in 4–20 mA loop-powered transmitters exposed to transient surges. IC Role / Device Role / Timing Role: Overvoltage protection element shunting excess energy during ESD or inductive kick events. Use Value: 33 V clamping threshold with 40 W non-repetitive peak power rating protects downstream op-amps without adding series impedance. |
| Telecom Power Supply Monitoring | Medical Diagnostic Equipment Biasing |
Use Scenario: Monitoring +48 V telecom rectifier output via resistive divider into MCU GPIO, requiring precise threshold detection. IC Role / Device Role / Timing Role: Precision voltage threshold detector using Zener breakdown as switching trigger point. Use Value: 33 V nominal Zener voltage with 29.7 mV/K tempco allows predictable trip-point compensation in firmware. |
Use Scenario: Generating stable bias voltages for photodiode transimpedance amplifiers in portable ultrasound front-ends. IC Role / Device Role / Timing Role: Low-noise DC reference source with minimal leakage-induced offset error. Use Value: 50 nA reverse leakage at 70 % VZ prevents measurable current injection into high-Z sensor nodes. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-C33-Q | ±5 % tolerance (31.4–34.7 V range) vs. ±2 % (32.3–33.7 V); identical package, power, and thermal specs. | Acceptable where system-level tolerance budget accommodates wider Zener spread; lower cost. | Select when absolute voltage accuracy is secondary to cost and footprint constraints. |
| MMSZ5261B-TP | 33 V ±5 %, SOD-123 package (2.7 × 1.4 mm), 500 mW Ptot, higher thermal resistance (350 K/W). | Higher power handling but larger footprint; not AEC-Q101 qualified-limited to industrial/commercial use. | Choose only if board space permits larger package and automotive qualification is unnecessary. |
Compared with BZX84W-C33-Q, the BZX84W-B33-QX offers tighter voltage control critical for precision references; versus MMSZ5261B-TP, it trades power headroom for AEC-Q101 compliance and 40 % smaller PCB area.
Availability
BZX84W-B33-QX is available at Aetrix Electronics and suitable for automotive ECU design, industrial sensor signal conditioning, telecom power monitoring, and medical diagnostic equipment requiring stable component supply across extended temperature ranges and lifecycle continuity.
Supply support for BZX84W-B33-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 essential semiconductors, delivering high-performance, reliable components for automotive, industrial, and consumer markets.
The BZX84W-Q series belongs to Nexperia's automotive-grade Zener diode product line, engineered specifically for robust voltage regulation and overvoltage protection in harsh-environment electronic control modules.
FAQ
What is the maximum continuous Zener current for BZX84W-B33-QX at 85 °C ambient?
At Tamb = 85 °C, derated power dissipation is 165 mW (using Rth(j-a) = 455 K/W and Tj(max) = 150 °C). With VZ ≈ 33 V, maximum continuous Zener current is ~5 mA-matching the test condition for nominal voltage specification and ensuring thermal safety.
Does Pin 2 require PCB connection or grounding?
No. Pin 2 is explicitly marked "n.c." (not connected) in the official Nexperia datasheet and has no internal bond wire or silicon connection. It must remain unconnected on the PCB-no trace, pad, or ground pour should contact this terminal.
How does the +29.7 mV/K temperature coefficient affect regulation stability?
The positive temperature coefficient means VZ increases by ~29.7 mV per Kelvin rise in junction temperature. At 33 V nominal, this yields ~0.09 %/°C drift-requiring thermal-aware layout (e.g., isolation from heat sources) in precision reference applications where <0.5 % total drift is required over −40 °C to +125 °C.
Can BZX84W-B33-QX be used in parallel for higher power handling?
No. Zener diodes exhibit manufacturing spread in VZ and rdif, causing current imbalance when paralleled-even with ±2 % tolerance. Uneven current sharing risks thermal runaway in one device. For higher power, select a single higher-rated Zener or implement active current balancing.
BZX84W-B33-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):
- 33 V
- Tolerance:
- ±2.12%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 80 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 23.1 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-B33-QX FAQ
1.How can I place an order for BZX84W-B33-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B33-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-B33-QX reliable?
The price and inventory of BZX84W-B33-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-B33-QX is usually 5 days.
3.What payment methods are accepted for BZX84W-B33-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B33-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B33-QX?
BZX84W-B33-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B33-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-B33-QX?
For technical support, including BZX84W-B33-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B33-QX requirements.
6.How does Aetrix verify that BZX84W-B33-QX is sourced from the original manufacturer or authorized distributors?
All BZX84W-B33-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-B33-QX meets industry standards.
7.What is the process for return or replacement of BZX84W-B33-QX?
All BZX84W-B33-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B33-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-B33-QX part is unused and in its original packaging.
Return procedure for BZX84W-B33-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B33-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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