My Inquiry
My Account
Nexperia USA Inc. BZX8450-B51-QR
- Part No.:
- BZX8450-B51-QR
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BZX8450-B51-QR.pdf
- Description:
- DIODE ZENER 51V 250MW TO236AB
- Quantity:
- Payment:
- Shipping:
Inventory:2,945
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX8450-B51-QR from Nexperia is a low-current Zener voltage regulator diode in SOT23 package, rated for 51 V nominal working voltage at 50 µA test current, with ±2 % tolerance, 250 mW total power dissipation, and AEC-Q101 qualification for automotive use.
For engineers reviewing the BZX8450-B51-QR datasheet, BZX8450-B51-QR pinout, BZX8450-B51-QR application, or BZX8450-B51-QR equivalent, this device is selected for precision low-bias voltage reference, ESD-protected signal clamping, and battery-powered sensor supply regulation where leakage and thermal stability are critical.
Technical Context
This Zener diode operates in reverse breakdown mode with a specified VZ of 50.0 V to 52.0 V at IZ = 50 µA, exhibiting a positive temperature coefficient of +0.05 mV/K and differential resistance of 400 Ω at IZ = 2 mA. Its low 50 µA test current enables stable regulation in ultra-low-power circuits.
The device features intentional minor leakage optimization per AN90031 for fast switching and noise reduction, and achieves 150 °C maximum junction temperature with Rth(j-a) = 500 K/W on FR4 PCB - enabling reliable operation in constrained automotive cabin and engine-control environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Working Voltage (VZ) | 50.0 V to 52.0 V at IZ = 50 µA - defines precise regulation point for 51 V nominal rail |
| Tolerance | ±2 % - ensures tight voltage accuracy without post-production trimming |
| Power Dissipation (Ptot) | 250 mW at Tamb ≤ 25 °C - supports continuous operation in compact SOT23 footprint |
| Differential Resistance (rdiff) | 400 Ω at IZ = 2 mA - determines load regulation error under varying current draw |
| Reverse Current (IR) | ≤ 0.05 µA at VR = 35.7 V - enables low-quiescent-current bias networks |
| Forward Voltage (VF) | ≤ 0.9 V at IF = 10 mA - limits conduction loss during forward surge events |
| Thermal Resistance (Rth(j-a)) | 500 K/W - defines junction-to-ambient temperature rise per watt on standard FR4 PCB |
Pinout & Package
Package: SOT23 plastic surface-mount package, 2.9 mm × 1.3 mm × 1.0 mm body, 1.9 mm lead pitch, 3-terminal configuration with anode, cathode, and not-connected terminal.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Connected to lower-potential side in reverse-biased Zener configuration; must be held at ≤ VZ − 0.9 V to avoid forward conduction |
| 2 | Not Connected (n.c.) | Electrically isolated internal pad - no PCB trace or solder connection required |
| 3 | Cathode (K) | Connected to regulated output node; carries full Zener current and defines reference potential |
Key Features
| Feature | Design Value |
|---|---|
| Low-test-current specification | VZ defined at 50 µA - enables accurate regulation in microamp-level bias circuits (e.g., CMOS sensor references) |
| AEC-Q101 qualification | Qualified for automotive applications including engine control units and body electronics - meets stress-test requirements for temperature cycling, HTRB, and ESD |
| Optimized leakage profile | Intentional minor leakage rise per AN90031 - reduces switching transients and high-frequency noise in feedback paths |
| Two-tolerance series | ±2 % (B-series) and ~±5 % (C-series) options - allows cost/performance trade-off without redesigning PCB layout |
Applications
| Automotive Cabin Sensor Reference | Portable Gas Detector Bias Supply |
|---|---|
Use Scenario: Providing stable 51 V reference for MEMS pressure sensor excitation in HVAC control modules. IC Role / Device Role / Timing Role: Zener voltage regulator establishing fixed bias voltage for bridge sensor excitation circuit. Use Value: ±2 % tolerance and low 50 µA test current ensure <0.5 % full-scale error across −40 °C to +125 °C ambient range. |
Use Scenario: Generating calibrated bias voltage for electrochemical gas sensing electrodes in handheld CO monitors. IC Role / Device Role / Timing Role: Precision shunt regulator supplying constant excitation voltage independent of battery discharge state. Use Value: 250 mW power rating and 400 Ω dynamic impedance maintain <10 mV regulation deviation over 1–10 µA load variation. |
| Industrial PLC Analog Input Protection | Medical Wearable Signal Clamping |
Use Scenario: Clamping transient overvoltage on 4–20 mA current-loop input stages of programmable logic controllers. IC Role / Device Role / Timing Role: Fast-response Zener clamp limiting input voltage to 51 V during surge events. Use Value: Non-repetitive peak reverse power dissipation of 40 W (tp = 100 µs) absorbs IEC 61000-4-5 Level 3 surges without degradation. |
Use Scenario: Protecting ADC inputs of ECG front-end ICs against ESD and electrode pop transients in ambulatory monitoring patches. IC Role / Device Role / Timing Role: Low-leakage shunt protector maintaining signal integrity below 51 V while adding <40 pF capacitance. Use Value: Diode capacitance of 40 pF at VR = 0 V and f = 1 MHz minimizes high-frequency attenuation in 10 kHz biosignal paths. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX84-C51-Q | ±5 % tolerance, higher rdiff (400 Ω → 180 Ω), same VZ range and SOT23 package | Accepts wider output voltage drift; suitable where calibration is performed downstream | Select when cost sensitivity outweighs need for tight regulation in non-critical bias rails |
| MMSZ5257B-7-F | 51 V nominal, ±5 %, 500 mW Ptot, DO-213AA package, 1000 h life test at 85 °C/85 % RH | Larger thermal mass and higher power rating; requires different PCB footprint | Choose for industrial systems requiring extended reliability validation beyond AEC-Q101 |
Compared with BZX8450-B51-QR, the BZX84-C51-Q trades voltage accuracy for cost and the MMSZ5257B-7-F offers higher power handling but sacrifices automotive qualification and SOT23 board-area efficiency.
Availability
BZX8450-B51-QR is available at Aetrix Electronics and suitable for automotive cabin electronics, portable gas detection systems, industrial PLC analog protection, and medical wearable signal conditioning requiring stable component supply with AEC-Q101 compliance and SOT23 space constraints.
Supply support for BZX8450-B51-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 high-volume, high-reliability discrete and logic devices, with leadership in automotive-qualified components and energy-efficient solutions.
The BZX8450-Q series belongs to Nexperia's automotive-grade Zener regulator portfolio, designed specifically for low-current, high-stability voltage reference and transient protection in space-constrained automotive and portable electronics.
FAQ
What is the maximum reverse voltage before breakdown for BZX8450-B51-QR?
The device exhibits a nominal Zener voltage (VZ) of 51 V, with guaranteed minimum and maximum values of 50.0 V and 52.0 V respectively at IZ = 50 µA. Breakdown occurs within this band; operation above 52.0 V risks exceeding absolute maximum ratings and thermal runaway.
Can BZX8450-B51-QR replace a 5.1 V Zener diode in a 5 V system?
No - BZX8450-B51-QR is a 51 V device, not 5.1 V. Its marking "%HN" corresponds exclusively to the 51 V B-series variant. Substituting it into a 5 V circuit would prevent proper regulation and likely damage downstream components due to excessive voltage.
Is the not-connected pin (Pin 2) required to be grounded or left floating on PCB?
Pin 2 is internally unconnected and must remain electrically isolated - no PCB trace, solder mask opening, or thermal pad should contact it. Routing copper beneath or adjacent to Pin 2 is permitted, but direct connection violates the SOT23 mechanical design and may cause assembly defects.
How does the "B" suffix differ from "C" in BZX8450-B51-QR vs. BZX8450-C51-Q?
The "B" denotes ±2 % VZ tolerance (50.0–52.0 V), while "C" indicates approximately ±5 % (48.0–54.0 V). Both share identical package, thermal specs, and AEC-Q101 qualification, but "B" is selected for precision reference applications where tighter regulation is mandatory.
BZX8450-B51-QR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX8450-Q
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 51 V
- Tolerance:
- ±2%
- 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-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-236AB
BZX8450-B51-QR FAQ
1.How can I place an order for BZX8450-B51-QR through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX8450-B51-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-B51-QR reliable?
The price and inventory of BZX8450-B51-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-B51-QR is usually 5 days.
3.What payment methods are accepted for BZX8450-B51-QR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX8450-B51-QR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX8450-B51-QR?
BZX8450-B51-QR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX8450-B51-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-B51-QR?
For technical support, including BZX8450-B51-QR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX8450-B51-QR requirements.
6.How does Aetrix verify that BZX8450-B51-QR is sourced from the original manufacturer or authorized distributors?
All BZX8450-B51-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-B51-QR meets industry standards.
7.What is the process for return or replacement of BZX8450-B51-QR?
All BZX8450-B51-QR units undergo pre-shipment inspection (PSI). If there is an issue with BZX8450-B51-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-B51-QR part is unused and in its original packaging.
Return procedure for BZX8450-B51-QR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX8450-B51-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
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
