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Nexperia USA Inc. BZX38450-B51-QX
- Part No.:
- BZX38450-B51-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-76, SOD-323
- Datasheet:
-
BZX38450-B51-QX.pdf
- Description:
- DIODE ZENER 51V 300MW SOD323
- Quantity:
- Payment:
- Shipping:
Inventory:3,315
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Product details
Overview
BZX38450-B51-QX from Nexperia is a low-current Zener voltage regulator diode in SOD323 (SC-76) package, rated for 51 V nominal working voltage at 50 µA test current, with ±2 % tolerance, 300 mW total power dissipation, and AEC-Q101 qualification for automotive use.
For engineers reviewing the BZX38450-B51-QX datasheet, BZX38450-B51-QX pinout, BZX38450-B51-QX application, or BZX38450-B51-QX equivalent, key selection factors include its low-bias operation at 50 µA, intentional leakage optimization for noise reduction per AN90031, thermal resistance of 415 K/W (junction-to-ambient), and cathode-marked SMD footprint compatibility with FR4 PCBs.
Technical Context
This device operates as a precision shunt voltage reference under reverse bias, with specified Zener voltage VZ = 50.0–52.0 V at IZ = 50 µA and differential resistance rdiff ≤ 400 Ω at IZ = 2 mA. Its temperature coefficient SZ is +0.05 mV/K, indicating near-zero drift over temperature.
The BZX38450-B51-QX features optimized leakage current for fast switching and reduced noise, per application note AN90031, and supports non-repetitive peak reverse power dissipation up to 40 W for tp = 100 µs pulses at Tj = 25 °C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VZ (nominal) | 51 V - Stable regulation point at low 50 µA test current, suitable for battery-powered sensor biasing |
| Tolerance | ±2 % - Tight voltage accuracy enables precise reference without trimming in automotive ECUs |
| Ptot | 300 mW - Maximum continuous power at Tamb ≤ 25 °C on standard FR4 PCB, defining thermal derating envelope |
| rdiff | ≤400 Ω - Low dynamic impedance ensures minimal output voltage variation under load transients |
| Rth(j-a) | 415 K/W - Junction-to-ambient thermal resistance limits max junction temperature to 150 °C at rated power |
| IR @ VR = 45.9 V | ≤0.05 µA - Ultra-low reverse leakage preserves battery life in always-on automotive modules |
| Cd @ f = 1 MHz | 40 pF - Low junction capacitance minimizes high-frequency noise coupling in signal conditioning paths |
Pinout & Package
SOD323 (SC-76) surface-mount plastic package: 1.7 mm × 1.25 mm × 0.95 mm body, 1.3 mm lead pitch, cathode marked by bar on top surface.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Cathode (K) | Connected to regulated voltage node; marking bar identifies this terminal for correct PCB orientation |
| 2 | Anode (A) | Connected to ground or lower-potential rail; forms reverse-biased junction for Zener operation |
Key Features
| Feature | Design Value |
|---|---|
| Low-test-current regulation | Specified at IZ = 50 µA - Enables stable reference generation in ultra-low-power wake-up circuits |
| AEC-Q101 qualification | Qualified for automotive applications - Meets stress test requirements for temperature cycling, HTRB, and ESD robustness |
| Optimized leakage profile | Intentional minor rise per AN90031 - Reduces switching noise and improves transient response in feedback loops |
| Thermal performance | Rth(j-sp) = 110 K/W to cathode solder point - Supports reliable operation under localized board heating in engine bay modules |
| Package footprint | SOD323 with standard reflow/wave solder lands - Compatible with high-volume automated assembly and IPC-7351B land patterns |
Applications
| Automotive Body Control Module (BCM) | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Voltage reference for analog front-end of LIN bus transceivers and door lock actuator drivers. IC Role / Device Role / Timing Role: Shunt regulator providing stable 51 V bias to protect input clamping networks and enable accurate current sensing. Use Value: ±2 % tolerance and AEC-Q101 qualification ensure long-term stability across −40 °C to +125 °C ambient, reducing calibration drift in field-deployed units. |
Use Scenario: Precision reference for 24 V industrial PLC analog input channels monitoring pressure/temperature transducers. IC Role / Device Role / Timing Role: Zener clamp establishing known upper rail for op-amp biasing and ADC reference scaling. Use Value: 40 pF capacitance and low rdiff minimize signal distortion at 1 kHz–10 kHz measurement bandwidths, preserving SNR in noisy factory environments. |
| Portable Medical Diagnostic Device | Automotive Infotainment Power Sequencing |
Use Scenario: Low-power voltage reference in handheld ECG monitor battery management circuitry. IC Role / Device Role / Timing Role: Regulator supplying bias to ultra-low-quiescent LDOs during standby mode. Use Value: 50 µA test current and ≤0.05 µA leakage at 90 % VZ extend single-cell Li-ion battery life beyond 72 hours in sleep state. |
Use Scenario: Soft-start voltage clamp in USB-C PD controller auxiliary supply sequencing. IC Role / Device Role / Timing Role: Transient suppressor and reference stabilizer during hot-plug events. Use Value: 40 W non-repetitive surge rating (tp = 100 µs) absorbs ESD-induced overshoot without degradation, maintaining system uptime. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX38450-C51-Q | ±5 % tolerance (vs. ±2 %), identical VZ range and package | Acceptable where cost-sensitive designs tolerate wider voltage spread | Select when absolute regulation accuracy is secondary to BOM cost reduction in non-critical bias rails |
| MMSZ5267B-7-F | 51 V, ±5 %, 500 mW Ptot, SOD-123 package (larger footprint) | Higher power handling but incompatible with SOD323 layout; no AEC-Q101 qualification | Choose only if thermal margin exceeds 300 mW requirement and automotive compliance is not required |
Compared with BZX38450-C51-Q, the BZX38450-B51-QX delivers tighter voltage control critical for precision analog stages; versus MMSZ5267B-7-F, it trades power headroom for automotive-grade reliability and space-constrained SOD323 integration.
Availability
BZX38450-B51-QX is available at Aetrix Electronics and suitable for automotive electronics, industrial sensor interfaces, and portable medical devices requiring stable component supply with AEC-Q101 assurance and tight voltage tolerance.
Supply support for BZX38450-B51-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 energy-efficient solutions.
The BZX38450-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode portfolio, engineered specifically for low-current, low-noise voltage regulation in harsh-environment automotive and industrial systems.
FAQ
What is the maximum continuous reverse current the BZX38450-B51-QX can sustain at 25 °C ambient?
The device has no defined maximum continuous reverse current; instead, its safe operating area is bounded by total power dissipation (300 mW at Tamb ≤ 25 °C) and junction temperature limit (150 °C). At VZ ≈ 51 V, this corresponds to ~5.9 mA average reverse current before thermal derating begins.
Does the BZX38450-B51-QX require external series resistance in typical regulation circuits?
Yes - a current-limiting resistor is mandatory to set the operating Zener current between 50 µA (minimum regulation) and the thermal limit (~5.9 mA). For example, with a 55 V supply, a 680 Ω resistor establishes ~5.9 mA, balancing regulation stability and power dissipation.
How does the "intentional minor rise of leakage current" improve performance?
Per AN90031, this controlled leakage reduces minority-carrier lifetime, decreasing reverse recovery time and minimizing switching-induced noise spikes-critical for clean biasing in high-gain amplifier stages and sensitive RF front-ends.
Can the BZX38450-B51-QX be used in parallel for higher power handling?
No - Zener diodes exhibit negative temperature coefficients and mismatched VZ tolerances, causing current hogging and thermal runaway when paralleled. Use a single higher-power device or active regulation instead.
BZX38450-B51-QX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX38450-Q
- Package/Case:
- SC-76, SOD-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 51 V
- Tolerance:
- ±2%
- Power - Max:
- 300 mW
- Impedance (Max) (Zzt):
- 180 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 35.7 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:
- SOD-323
BZX38450-B51-QX FAQ
1.How can I place an order for BZX38450-B51-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX38450-B51-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 BZX38450-B51-QX reliable?
The price and inventory of BZX38450-B51-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX38450-B51-QX is usually 5 days.
3.What payment methods are accepted for BZX38450-B51-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX38450-B51-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX38450-B51-QX?
BZX38450-B51-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX38450-B51-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 BZX38450-B51-QX?
For technical support, including BZX38450-B51-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX38450-B51-QX requirements.
6.How does Aetrix verify that BZX38450-B51-QX is sourced from the original manufacturer or authorized distributors?
All BZX38450-B51-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 BZX38450-B51-QX meets industry standards.
7.What is the process for return or replacement of BZX38450-B51-QX?
All BZX38450-B51-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX38450-B51-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 BZX38450-B51-QX part is unused and in its original packaging.
Return procedure for BZX38450-B51-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX38450-B51-QX Tags
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