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Nexperia USA Inc. BZX84W-B56X
- Part No.:
- BZX84W-B56X
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-70, SOT-323
- Datasheet:
-
BZX84W-B56X.pdf
- Description:
- DIODE ZENER 56V 275MW SOT323
- Quantity:
- Payment:
- Shipping:
Inventory:3,202
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Product details
Overview
BZX84W-B56X from Nexperia is a ±2 % tolerance Zener voltage regulator diode with nominal 56 V breakdown voltage, 425 Ω differential resistance at 2 mA, and 57.0 mV/K temperature coefficient, housed in a SOT323 (SC-70) package for precision voltage reference and overvoltage protection in compact power supply rails.
For engineers reviewing the BZX84W-B56X datasheet, BZX84W-B56X pinout, BZX84W-B56X application, or BZX84W-B56X equivalent, this device serves as a stable 56 V shunt regulator in low-power analog circuits, ESD-clamped signal conditioning paths, and microcontroller reset supervision where tight voltage tolerance and low thermal drift are required.
Technical Context
This Zener diode operates in reverse-biased breakdown mode to maintain a stable 56 V reference across its cathode-anode terminals under regulated current conditions (IZ = 2 mA). Its ±2 % tolerance ensures initial accuracy within ±1.12 V of nominal, while the +57.0 mV/K temperature coefficient indicates predictable positive drift with junction heating.
The device exhibits 425 Ω differential resistance at IZ = 2 mA, limiting output impedance in regulation, and supports non-repetitive peak reverse power dissipation up to 40 W for surge suppression. Thermal resistance from junction to ambient is 455 K/W on standard FR4 PCB mounting.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 54.9 V to 57.1 V at IZ = 2 mA - defines precise regulation window for 56 V nominal reference |
| Tolerance | ±2 % - guarantees initial voltage accuracy without post-manufacturing trimming |
| Differential Resistance (rdif) | 425 Ω at IZ = 2 mA - determines load regulation error sensitivity to current variation |
| Temperature Coefficient (SZ) | +57.0 mV/K - quantifies voltage drift per degree rise in junction temperature |
| Total 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 = 39.2 V - specifies leakage below regulation threshold, critical for low-power standby |
| Forward Voltage (VF) | 0.9 V at IF = 10 mA - defines anode-cathode drop during forward conduction, relevant for bidirectional clamping |
Pinout & Package
SOT323 (SC-70) leadless surface-mount plastic package with 3 terminals; ultra-compact footprint (2.2 mm × 1.35 mm × 0.95 mm) optimized for high-density PCB layouts and reflow/wave soldering.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward current entry point; connected to lower-potential node in shunt regulation configuration |
| 2 | Not Connected (n.c.) | Electrically isolated terminal; no internal bond wire or die connection - must remain unconnected in layout |
| 3 | Cathode (K) | Reverse-bias terminal; connected to higher-potential node and current-limiting resistor in Zener regulator topology |
Key Features
| Feature | Design Value |
|---|---|
| ±2 % Zener voltage tolerance | Enables direct use in 56 V reference designs without external calibration or trimming circuitry |
| Low thermal resistance (455 K/W) | Supports stable regulation under ambient temperature swings up to +150 °C without derating |
| Non-repetitive peak reverse power (40 W) | Provides transient overvoltage clamping capability for ESD and surge events per IEC 61000-4-2 |
| 3-terminal SOT323 package with n.c. pin | Allows mechanical anchoring and thermal relief via unused pin while maintaining minimal board area |
| 50 nA reverse leakage at 70 % VZ | Minimizes quiescent current draw in battery-powered or always-on monitoring circuits |
Applications
| Power Supply Reference | Microcontroller Reset Supervision |
|---|---|
|
Use Scenario: Providing stable 56 V reference for feedback loop in isolated flyback converter secondary-side regulation. IC Role / Device Role / Timing Role: Shunt voltage reference establishing precise output voltage setpoint via optocoupler feedback path. Use Value: ±2 % tolerance eliminates need for external potentiometer adjustment; 425 Ω rdif ensures <0.5 % load regulation error across 1–5 mA bias range. |
Use Scenario: Monitoring 56 V rail to assert reset signal when voltage drops below safe operating threshold. IC Role / Device Role / Timing Role: Precision Zener element in comparator-based reset generator circuit with hysteresis. Use Value: +57.0 mV/K temperature coefficient enables predictable trip-point shift across industrial temperature range (−40 °C to +125 °C). |
| ESD-Clamped Signal Conditioning | Overvoltage Protection for Analog Sensors |
|
Use Scenario: Bidirectional clamping of ±12 V analog sensor interface lines against fast transients. IC Role / Device Role / Timing Role: Low-capacitance (0.3 pF) Zener pair used back-to-back with series resistor for I/O line protection. Use Value: 0.9 V forward voltage ensures low-threshold conduction during positive surges; 50 nA leakage preserves signal integrity at DC. |
Use Scenario: Protecting 56 V-rated pressure transducer output from accidental 72 V supply fault. IC Role / Device Role / Timing Role: Primary shunt clamp absorbing fault energy until upstream fuse opens. Use Value: 40 W non-repetitive peak power rating sustains 100 µs surge without degradation; 275 mW Ptot allows continuous dissipation during sustained overvoltage. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84W-C56 | ±5 % tolerance (52.0 V–60.0 V), higher 500 Ω rdif, +57.0 mV/K SZ | Acceptable where 56 V ±4 V tolerance suffices; less stable under varying load current | Select for cost-sensitive designs where tighter regulation is not required |
| MMSZ5256B | ±5 % tolerance, 500 Ω rdif, +57 mV/K SZ, same SOT323 package but no n.c. pin | Requires PCB redesign due to 2-pin vs. 3-pin footprint; identical thermal performance on FR4 | Choose only if legacy MMSZ5256B stock exists and layout revision is impractical |
Compared with BZX84W-B56X, BZX84W-C56 trades initial accuracy for lower unit cost, while MMSZ5256B sacrifices pin compatibility and requires layout change-neither offers the ±2 % tolerance and mechanically anchored 3-pin SOT323 of the original.
Availability
BZX84W-B56X is available at Aetrix Electronics and suitable for precision voltage reference, microcontroller reset supervision, ESD-clamped signal conditioning, and overvoltage protection requiring stable component supply across automotive-grade-adjacent industrial and telecom power systems.
Supply support for BZX84W-B56X 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 delivering high-performance logic, analog, and discrete components with focus on efficiency, reliability, and miniaturization for industrial, consumer, and communications markets.
BZX84W-B56X belongs to the BZX84W series of general-purpose Zener diodes designed specifically for space-constrained, high-frequency regulation and protection applications where SOT323 packaging and tight voltage tolerance are essential.
FAQ
What is the maximum continuous reverse current the BZX84W-B56X can sustain at 25 °C?
The device supports a maximum continuous reverse current of 200 mA, derived from its 275 mW total power dissipation rating and 56 V nominal Zener voltage (IZmax = Ptot/VZ ≈ 4.9 mA typical operating point; absolute max IF = 200 mA applies to forward conduction only). In Zener mode, practical regulation current is limited to 2–10 mA for stability and thermal management.
Can the n.c. pin (Pin 2) be grounded or left floating in PCB layout?
Pin 2 is internally unconnected and must remain electrically floating - neither grounded nor tied to any net. Grounding it risks unintended parasitic coupling or solder bridging; leaving it unconnected per datasheet pinning ensures mechanical stability and avoids compromising the specified thermal resistance of 455 K/W on FR4.
How does the +57.0 mV/K temperature coefficient affect regulation accuracy over −40 °C to +125 °C?
Across this 165 K range, the Zener voltage shifts by +9.4 V (57.0 mV/K × 165 K), resulting in a total span of 54.9 V to 66.3 V. For applications requiring tighter thermal stability, this drift must be compensated in system-level design - e.g., using a temperature-sensing ADC to adjust digital setpoints or selecting a lower-coefficient Zener like BZX84W-B33 (+12.4 mV/K).
Is BZX84W-B56X qualified for automotive applications?
No. Per Nexperia's revision history (Rev. 2, Jan 2023), the BZX84W series is explicitly non-automotive qualified. It lacks AEC-Q200 stress testing and automotive-grade process controls. For automotive use, engineers must select the -Q qualified variant (e.g., BZX84W-B56-Q) or consult Nexperia's automotive portfolio directly.
BZX84W-B56X Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX84W
- Package/Case:
- SC-70, SOT-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 56 V
- Tolerance:
- ±2%
- Power - Max:
- 275 mW
- Impedance (Max) (Zzt):
- 200 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 39.2 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-323
BZX84W-B56X FAQ
1.How can I place an order for BZX84W-B56X through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX84W-B56X 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-B56X reliable?
The price and inventory of BZX84W-B56X are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX84W-B56X is usually 5 days.
3.What payment methods are accepted for BZX84W-B56X?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX84W-B56X transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX84W-B56X?
BZX84W-B56X orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX84W-B56X 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-B56X?
For technical support, including BZX84W-B56X datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX84W-B56X requirements.
6.How does Aetrix verify that BZX84W-B56X is sourced from the original manufacturer or authorized distributors?
All BZX84W-B56X 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-B56X meets industry standards.
7.What is the process for return or replacement of BZX84W-B56X?
All BZX84W-B56X units undergo pre-shipment inspection (PSI). If there is an issue with BZX84W-B56X, 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-B56X part is unused and in its original packaging.
Return procedure for BZX84W-B56X:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX84W-B56X Tags
-
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
-
MM5Z5V1ST1G
onsemi
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SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
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