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Nexperia USA Inc. BZX8450-C51-QR
- Part No.:
- BZX8450-C51-QR
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BZX8450-C51-QR.pdf
- Description:
- DIODE ZENER 51V 250MW TO236AB
- Quantity:
- Payment:
- Shipping:
Inventory:2,891
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Product details
Overview
BZX8450-C51-QR from Nexperia is a low-current Zener voltage regulator diode in SOT23 package, rated for 51 V nominal working voltage (±5 % tolerance), 250 mW total power dissipation, and specified at 50 µA test current - optimized for low-bias regulation in automotive sensor interfaces and portable battery-powered systems.
For engineers reviewing the BZX8450-C51-QR datasheet, BZX8450-C51-QR pinout, BZX8450-C51-QR application, or BZX8450-C51-QR equivalent, this part supports precision low-power voltage reference, reverse-polarity protection, and overvoltage clamping where tight thermal stability and AEC-Q101 qualification are required.
Technical Context
This Zener diode operates in reverse breakdown with a nominal VZ of 51 V at IZ = 2 mA, exhibiting a temperature coefficient of +0.05 mV/K and differential resistance of 400 Ω at IZ = 2 mA. Its leakage current is intentionally elevated per AN90031 to improve switching speed and reduce noise.
Qualified to AEC-Q101, it sustains junction temperatures up to 150 °C and ambient ranges from −55 °C to +150 °C. Thermal resistance from junction to solder point is 330 K/W on FR4 PCB, enabling stable operation in constrained automotive ECUs without forced cooling.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Nominal Zener Voltage | 51 V ±5 % at IZ = 2 mA - defines precise clamping threshold for 48 V system overvoltage protection |
| Total Power Dissipation | 250 mW at Tamb ≤ 25 °C - limits continuous regulation current to ~4.9 mA at 51 V |
| Forward Voltage | 0.9 V max at IF = 10 mA - ensures minimal forward drop in series polarity protection configurations |
| Differential Resistance | 400 Ω max at IZ = 2 mA - determines output impedance and load regulation error under varying current |
| Reverse Current | 0.05 µA max at VR = 38.3 V - guarantees low standby leakage in always-on automotive modules |
| Junction Temperature | 150 °C max - enables deployment in engine bay or powertrain control units without derating |
| AEC-Q101 Qualified | Yes - validated for automotive-grade reliability including HTOL, TC, HAST, and ESD testing |
Pinout & Package
Package: SOT23 plastic surface-mount package (2.9 mm × 1.3 mm × 1.0 mm body, 1.9 mm pin pitch), optimized for automated placement and reflow soldering on FR4 PCBs with single-sided 70 µm copper.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Connects to lower-potential node; reverse-biased during regulation; must be routed with low-inductance trace for transient suppression |
| 2 | Not Connected (n.c.) | Internally unconnected terminal; must remain floating - no PCB pad connection or routing allowed |
| 3 | Cathode (K) | Connects to higher-potential node; carries full Zener current during clamping; serves as primary thermal path to PCB copper |
Key Features
| Feature | Design Value |
|---|---|
| Low test current specification | Rated at 50 µA - enables stable regulation in microamp-level bias networks for IoT sensors and wake-up circuits |
| Optimized leakage profile | Intentional minor rise per AN90031 - reduces switching transients and broadband noise in CAN/LIN bus protection |
| Automotive qualification | AEC-Q101 compliant - qualified for under-hood and chassis-mounted applications requiring extended temperature and lifetime reliability |
| Tight thermal resistance | Rth(j-sp) = 330 K/W - allows direct thermal coupling to cathode pad for passive heat dissipation in space-constrained modules |
| Standard marking code | "LV%" laser marking - enables automated optical inspection and traceability in high-volume automotive manufacturing |
Applications
| Automotive Sensor Reference | Portable Battery Monitor |
|---|---|
|
Use Scenario: Providing stable 51 V reference for analog front-end of 48 V mild-hybrid vehicle battery management ICs. IC Role / Device Role / Timing Role: Zener shunt regulator establishing precision voltage rail for ADC reference and comparator thresholds. Use Value: ±5 % tolerance and +0.05 mV/K tempco ensure <±1.5 % reference drift across −40 °C to +125 °C operating range. |
Use Scenario: Clamping input of fuel gauge IC during hot-swap events in handheld medical devices powered by Li-ion packs. IC Role / Device Role / Timing Role: Overvoltage protector limiting surge energy into sensitive analog measurement circuitry. Use Value: 40 W non-repetitive peak power rating (100 µs) absorbs transient spikes without degradation. |
| Industrial CAN Transceiver Bias | Smart Actuator Feedback Clamp |
|
Use Scenario: Supplying regulated bias to isolated CAN FD transceiver's VIO pin in programmable logic controller backplane modules. IC Role / Device Role / Timing Role: Low-current voltage source maintaining logic-level compatibility across wide supply variations. Use Value: 250 mW dissipation and 400 Ω rdiff enable stable 51 V rail despite 1–5 mA dynamic load changes. |
Use Scenario: Protecting position feedback amplifier input from inductive kickback in 24/48 V DC motor drives. IC Role / Device Role / Timing Role: Fast-switching clamp limiting reverse voltage to safe levels during MOSFET turn-off. Use Value: Elevated leakage design reduces ringing and EMI during 100 ns–1 µs transients in PWM-driven systems. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84-C51,115 (Nexperia) | Same 51 V rating but ±5 % tolerance, non-AEC-Q101, no intentional leakage optimization | Limited to industrial/commercial use; lacks automotive qualification and fast-switching noise reduction | Select when AEC-Q101 compliance and low-noise clamping are not required |
| MMSZ5257B-TP (Micro Commercial Co) | 51 V ±5 %, 500 mW Ptot, 1000 Ω rdiff at 20 mA, no AEC-Q101, SOD-123 package | Higher power handling but larger footprint and inferior thermal resistance; unsuitable for dense automotive layouts | Select only if board space permits SOD-123 and higher continuous power is needed |
Compared with BZX8450-C51-QR, the BZX84-C51,115 lacks automotive qualification and noise-optimized leakage, while MMSZ5257B-TP trades AEC-Q101 compliance and SOT23 compactness for higher power - making the BZX8450-C51-QR uniquely suited for space-constrained, safety-critical 48 V automotive subsystems.
Availability
BZX8450-C51-QR is available at Aetrix Electronics and suitable for automotive sensor interfaces, portable battery monitoring, industrial CAN transceiver biasing, and smart actuator feedback clamping requiring stable component supply across extended temperature and lifecycle demands.
Supply support for BZX8450-C51-QR 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 efficiency technologies, delivering high-performance, reliable discrete and logic devices for automotive, industrial, and consumer markets.
The BZX8450-Q series belongs to Nexperia's AEC-Q101-qualified Zener diode portfolio, engineered specifically for low-current voltage regulation in harsh-environment automotive electronics where precision, noise immunity, and long-term stability are critical.
FAQ
What is the maximum reverse voltage before breakdown for BZX8450-C51-QR?
The nominal Zener voltage is 51 V with ±5 % tolerance, meaning guaranteed breakdown occurs between 48.45 V and 53.55 V at IZ = 2 mA. The absolute maximum non-repetitive peak reverse voltage is limited by PZSM = 40 W for 100 µs pulses, not by fixed VR rating.
Can BZX8450-C51-QR replace standard 51 V Zeners in existing designs?
Yes, provided the design accommodates its SOT23 footprint, 250 mW power limit, and intentional leakage profile. It is not a drop-in replacement for higher-power Zeners like MMSZ5257B; verify thermal margin and transient response, especially in noise-sensitive applications.
Is pin 2 truly unused, or does it require grounding?
Pin 2 is internally not connected (n.c.) per Table 2 and must remain unconnected on the PCB. Grounding or routing to any net violates the device's internal construction and may cause parametric shift or premature failure due to parasitic coupling.
How does the "intentional minor rise of leakage current" affect circuit performance?
This controlled leakage (per AN90031) reduces minority-carrier storage time, enabling faster turn-off during transient clamping and lowering high-frequency noise generation - beneficial in CAN/LIN bus protection and precision analog reference circuits where ringing degrades signal integrity.
BZX8450-C51-QR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Voltage - Zener (Nom) (Vz):
- 51 V
- Tolerance:
- ±5%
- Power - Max:
- 250 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-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-236AB
BZX8450-C51-QR FAQ
1.How can I place an order for BZX8450-C51-QR through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX8450-C51-QR 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 BZX8450-C51-QR reliable?
The price and inventory of BZX8450-C51-QR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX8450-C51-QR is usually 5 days.
3.What payment methods are accepted for BZX8450-C51-QR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX8450-C51-QR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX8450-C51-QR?
BZX8450-C51-QR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX8450-C51-QR 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 BZX8450-C51-QR?
For technical support, including BZX8450-C51-QR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX8450-C51-QR requirements.
6.How does Aetrix verify that BZX8450-C51-QR is sourced from the original manufacturer or authorized distributors?
All BZX8450-C51-QR 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 BZX8450-C51-QR meets industry standards.
7.What is the process for return or replacement of BZX8450-C51-QR?
All BZX8450-C51-QR units undergo pre-shipment inspection (PSI). If there is an issue with BZX8450-C51-QR, 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 BZX8450-C51-QR part is unused and in its original packaging.
Return procedure for BZX8450-C51-QR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX8450-C51-QR 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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