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Nexperia USA Inc. BZX58550-B33X
- Part No.:
- BZX58550-B33X
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-79, SOD-523
- Datasheet:
-
BZX58550-B33X.pdf
- Description:
- DIODE ZENER 33V 270MW SOD523
- Quantity:
- Payment:
- Shipping:
Inventory:7,799
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Product details
Overview
BZX58550-B33X from Nexperia is a low-current Zener voltage regulator diode in SOD523 (SC-79) package, rated for 33 V nominal regulation at 50 µA test current, with ±2 % tolerance, 300 mW total power dissipation, and 25.0 Ω differential resistance at 5 mA - optimized for low-bias, battery-powered portable electronics requiring stable reference voltage under light load.
For engineers reviewing the BZX58550-B33X datasheet, BZX58550-B33X pinout, BZX58550-B33X application, or BZX58550-B33X equivalent, key selection criteria include its ultra-small SOD523 footprint, low leakage behavior per AN90031, tight 33 V ±2 % tolerance, 25.0 Ω dynamic impedance at 5 mA, and suitability for precision biasing in wearables, sensor nodes, and low-power microcontroller reset circuits.
Technical Context
This device operates as a two-terminal shunt voltage regulator, maintaining a stable 33 V reverse breakdown voltage across its cathode–anode terminals when biased above its knee current. Its specified test condition of IZ = 50 µA enables reliable operation in ultra-low-power standby modes.
The BZX58550-B33X belongs to the "B" tolerance series (±2 %), exhibits a temperature coefficient of +27.4 mV/K, and features intentional minor leakage current rise per AN90031 to improve switching speed and reduce noise in sensitive analog signal paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Nominal Zener Voltage | 33 V at IZ = 50 µA - defines precise regulation point for low-current bias networks |
| Tolerance | ±2 % - ensures tight voltage accuracy without post-manufacturing trimming |
| Differential Resistance | 25.0 Ω at IZ = 5 mA - determines output impedance and load regulation sensitivity |
| Power Dissipation | 300 mW at Tamb ≤ 25 °C on FR4 PCB with 35 mm² cathode copper - sets maximum continuous DC power handling |
| Forward Voltage | 0.9 V at IF = 10 mA - defines conduction threshold in forward-biased protection or clamping roles |
| Reverse Current | 0.05 µA at VR = 25.0 V - quantifies leakage in high-impedance sensing or reference applications |
| Temperature Coefficient | +27.4 mV/K - indicates positive drift with junction temperature, critical for thermal stability design |
Pinout & Package
Package: SOD523 (SC-79), ultra-small surface-mount plastic package measuring 1.2 mm × 0.8 mm × 0.6 mm, with flat lead profile and cathode band marking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (K) | Cathode | Connected to regulated voltage node; marked by bar on package body; carries reverse current during regulation |
| 2 (A) | Anode | Connected to ground or lower-potential rail; completes shunt path for excess current during overvoltage events |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-compact SMD footprint | SOD523 package (1.2 × 0.8 mm) enables placement in space-constrained wearable and IoT PCBs |
| Low test current specification | Regulation defined at 50 µA - supports energy harvesting and coin-cell-powered systems with sub-100 µA quiescent budgets |
| Controlled leakage behavior | Intentional minor IR rise per AN90031 improves transient response and reduces broadband noise in precision references |
| Tight voltage tolerance | ±2 % (B-series) eliminates need for external trimming in factory-calibrated sensor front-ends |
| Thermal robustness | 150 °C max junction temperature and 285 K/W Rth(j-a) on 1 cm² cathode pad support reliable operation in sealed enclosures |
Applications
| Portable Sensor Biasing | Microcontroller Reset Reference |
|---|---|
|
Use Scenario: Providing stable 33 V reference for analog front-end amplifiers in battery-operated environmental sensors. IC Role / Device Role / Timing Role: Shunt voltage regulator establishing fixed bias point for op-amp rails and ADC reference dividers. Use Value: ±2 % tolerance and 25.0 Ω rdiff ensure <1 % reference drift across 0–100 µA load variation, extending battery life via 50 µA test current compatibility. |
Use Scenario: Generating clean, noise-immune reset threshold for ultra-low-power MCUs in smart tags. IC Role / Device Role / Timing Role: Precision Zener element in RC-based reset generator circuit, defining VRESET trip point. Use Value: Controlled leakage per AN90031 minimizes timing jitter in reset assertion, while SOD523 size allows integration adjacent to MCU reset pin without layout congestion. |
| Wearable Power Rail Clamping | Low-Power ADC Reference Divider |
|
Use Scenario: Protecting 3.3 V logic inputs from transient overvoltage in compact hearable devices. IC Role / Device Role / Timing Role: Reverse-biased clamp limiting surge voltage to 33 V, diverting excess energy to ground. Use Value: 300 mW Ptot and 40 W non-repetitive peak power rating enable single-event ESD suppression without thermal runaway in confined earbud PCBs. |
Use Scenario: Creating accurate 3.3 V reference from 33 V supply in medical patch monitors using resistor divider + buffer. IC Role / Device Role / Timing Role: Primary voltage reference source feeding high-impedance resistive divider network. Use Value: +27.4 mV/K temperature coefficient allows predictable compensation in body-temperature-varying applications, and 0.05 µA leakage prevents loading error in >10 MΩ divider arms. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX58550-C33 | ±5 % tolerance (vs. ±2 %), identical 33 V nominal, same SOD523 package and thermal specs | Acceptable where cost sensitivity outweighs precision; higher unit-to-unit VZ spread increases calibration burden | Select for cost-driven consumer wearables where system-level trimming compensates for looser tolerance |
| MMSZ5261B | 33 V ±5 %, SOD-123 package (2.7 × 1.4 mm), 500 mW Ptot, 35 Ω rdiff at 20 mA | Larger footprint and higher power rating suit industrial modules; less suitable for sub-2 mm² wearable layouts | Choose when board space permits and higher surge immunity or legacy footprint compatibility is required |
Compared with BZX58550-C33, the BZX58550-B33X delivers tighter regulation accuracy critical for untrimmed sensor references; versus MMSZ5261B, it trades absolute power handling for 55 % smaller area and lower leakage - essential for miniaturized, battery-limited designs.
Availability
BZX58550-B33X is available at Aetrix Electronics and suitable for portable sensor biasing, microcontroller reset reference generation, wearable power rail clamping, and low-power ADC reference divider applications requiring stable component supply across high-mix, low-volume production runs.
Supply support for BZX58550-B33X 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 and energy-efficient components.
The BZX58550 series is part of Nexperia's precision low-current Zener portfolio, engineered specifically for battery-constrained portable electronics needing stable voltage references at microampere bias currents.
FAQ
What is the maximum continuous reverse current the BZX58550-B33X can handle at 25 °C ambient?
The device supports up to 200 mA forward current (IF), but as a Zener regulator, its continuous reverse current is limited by power dissipation. At 25 °C ambient on an FR4 PCB with 35 mm² cathode copper, the 300 mW Ptot rating allows ~9.1 mA average reverse current at 33 V (P = V × I). Exceeding this risks thermal runaway due to positive temperature coefficient.
Does the BZX58550-B33X require a series current-limiting resistor in all applications?
Yes - like all shunt Zeners, it must be used with a series resistor to limit reverse current and prevent exceeding Ptot. For example, with a 36 V supply and 33 V regulation, a 330 Ω resistor limits worst-case current to ~9.1 mA at 25 °C, staying within 300 mW. The resistor value must be recalculated for worst-case supply and temperature conditions.
How does the "intentional minor rise of leakage current" benefit circuit performance?
Per Application Note AN90031, this controlled leakage improves charge carrier mobility in the depletion region, reducing turn-on delay and minimizing high-frequency noise generation during transient events - making the device especially effective in low-noise reference and fast-reset applications where conventional Zeners exhibit ringing or slow settling.
Can the BZX58550-B33X be used in place of a 3.3 V Zener for level-shifting?
No - the BZX58550-B33X is a 33 V device, not 3.3 V. Substituting it for a 3.3 V Zener would result in catastrophic overvoltage at the regulated node. For 3.3 V regulation, use BZX58550-B3V3 (3.3 V ±2 %), which shares identical SOD523 packaging, thermal behavior, and low-current optimization.
BZX58550-B33X Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX58550
- Package/Case:
- SC-79, SOD-523
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 33 V
- Tolerance:
- ±2%
- Power - Max:
- 270 mW
- Impedance (Max) (Zzt):
- 80 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 25 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOD-523
BZX58550-B33X FAQ
1.How can I place an order for BZX58550-B33X through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX58550-B33X 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 BZX58550-B33X reliable?
The price and inventory of BZX58550-B33X are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX58550-B33X is usually 5 days.
3.What payment methods are accepted for BZX58550-B33X?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX58550-B33X transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX58550-B33X?
BZX58550-B33X orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX58550-B33X 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 BZX58550-B33X?
For technical support, including BZX58550-B33X datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX58550-B33X requirements.
6.How does Aetrix verify that BZX58550-B33X is sourced from the original manufacturer or authorized distributors?
All BZX58550-B33X 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 BZX58550-B33X meets industry standards.
7.What is the process for return or replacement of BZX58550-B33X?
All BZX58550-B33X units undergo pre-shipment inspection (PSI). If there is an issue with BZX58550-B33X, 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 BZX58550-B33X part is unused and in its original packaging.
Return procedure for BZX58550-B33X:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX58550-B33X Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
-
MMSZ5231B-7-F
Diodes Incorporated
-
BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
-
BZT52C15S-7-F
Diodes Incorporated
-
MM5Z5V1ST1G
onsemi
-
SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
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