My Inquiry
My Account
Nexperia USA Inc. BZX38450-B3V9X
- Part No.:
- BZX38450-B3V9X
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-76, SOD-323
- Datasheet:
-
BZX38450-B3V9X.pdf
- Description:
- DIODE ZENER 3.9V 300MW SOD323
- Quantity:
- Payment:
- Shipping:
Inventory:9,566
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX38450-B3V9X from Nexperia is a low-current Zener voltage regulator diode in SOD323 (SC-76) package, designed for precision biasing and voltage reference in ultra-low-power circuits. It delivers a nominal 3.9 V regulation at 50 µA test current, with ±2 % tolerance, 600 Ω dynamic resistance at 5 mA, and 2.0 µA max reverse leakage at VR = 3.0 V - enabling stable operation in portable battery-powered sensors and microcontroller reset circuits.
For engineers reviewing the BZX38450-B3V9X datasheet, BZX38450-B3V9X pinout, BZX38450-B3V9X application, or BZX38450-B3V9X equivalent, this page provides verified electrical characteristics, thermal behavior, SOD323 mounting guidance, and direct comparison to functionally aligned Zener alternatives for low-bias analog and digital subsystems.
Technical Context
This device operates as a two-terminal shunt voltage regulator, maintaining a stable 3.9 V reference across its cathode–anode terminals under reverse-biased conditions. Its specified test current of 50 µA enables accurate regulation in sub-100 µA bias networks, while its 600 Ω differential resistance at 5 mA ensures minimal voltage drift under light load variation.
The BZX38450-B3V9X belongs to the "B" tolerance series (±2 %), features a temperature coefficient of −2.7 mV/K, and exhibits 150 pF junction capacitance at 0 V - making it suitable for noise-sensitive signal conditioning paths where low parasitic capacitance and predictable thermal drift are critical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Nominal Zener Voltage (VZ) | 3.9 V at IZ = 50 µA - defines primary regulation point for low-current reference design |
| Tolerance | ±2 % - ensures tight voltage accuracy without post-calibration in production |
| Differential Resistance (rdiff) | 600 Ω max at IZ = 5 mA - limits output voltage shift under small load changes |
| Reverse Leakage Current (IR) | 2.0 µA max at VR = 3.0 V - minimizes quiescent power draw in always-on circuits |
| Forward Voltage (VF) | 0.9 V max at IF = 10 mA - supports use as low-drop rectifier or clamp in dual-role layouts |
| Total Power Dissipation (Ptot) | 300 mW at Tamb ≤ 25 °C - sets thermal derating boundary on standard FR4 PCB |
| Junction-to-Ambient Rth | 415 K/W - informs minimum copper area needed for sustained 250 mA surge handling |
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 (K) | Cathode | Connected to regulated voltage node; marking bar identifies this terminal |
| 2 (A) | Anode | Connected to ground or lower-potential rail; completes reverse-bias path |
Key Features
| Feature | Design Value |
|---|---|
| Low test current specification | 50 µA - enables accurate regulation in µA-level bias networks without loading source |
| Controlled temperature coefficient | −2.7 mV/K - reduces thermal drift in ambient-varying sensor front-ends |
| Optimized leakage profile | 2.0 µA max at 3.0 V - preserves battery life in always-on IoT endpoint regulators |
| Small-outline SMD package | SOD323 footprint - supports high-density layout in space-constrained wearables and modules |
| Two-tolerance series | ±2 % (B-series) and ~±5 % (C-series) - allows cost/performance trade-off per application tier |
Applications
| Microcontroller Reset Circuit | Portable Sensor Bias Reference |
|---|---|
Use Scenario: Provides clean, stable 3.9 V threshold for brown-out detection in ARM Cortex-M0+ MCUs powered by coin cells. IC Role / Device Role / Timing Role: Shunt Zener reference defining reset assertion voltage level during supply ramp-up or sag. Use Value: ±2 % tolerance ensures deterministic reset timing across temperature; 50 µA test current avoids draining CR2032 during standby. |
Use Scenario: Supplies precise bias to MEMS accelerometer analog front-end in Bluetooth LE fitness tracker. IC Role / Device Role / Timing Role: Low-noise voltage reference stabilizing op-amp gain-setting network and ADC reference divider. Use Value: 150 pF capacitance and −2.7 mV/K TC minimize signal path error and thermal offset drift over −20 °C to +70 °C. |
| USB-C Port Protection Clamp | Low-Power RTC Backup Regulator |
Use Scenario: Clamps transient overvoltage on USB-C CC line during hot-plug events in embedded host controllers. IC Role / Device Role / Timing Role: Fast-reacting shunt limiter absorbing ESD pulses while holding line below 4.3 V. Use Value: 40 W non-repetitive peak power rating (100 µs) handles IEC 61000-4-2 Level 4 surges without degradation. |
Use Scenario: Regulates backup voltage for real-time clock IC during main supply failure in industrial HMIs. IC Role / Device Role / Timing Role: Standby-mode Zener maintaining 3.9 V rail for RTC oscillator and SRAM retention. Use Value: 2.0 µA max leakage at 3.0 V extends CR1220 battery life beyond 5 years in maintenance-free deployments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX384-C3V9 | ±5 % tolerance, higher 7.0 µA leakage at 3.0 V, same SOD323 package | Acceptable where cost sensitivity outweighs precision; unsuitable for <1 µA standby systems | Select when budget constraints dominate and ±5 % regulation error is acceptable in final calibration |
| MMSZ4685T1G | 3.9 V nominal, ±5 %, 100 Ω rdiff at 5 mA, 100 pF Cj, SOD-123 package | Lower impedance improves load regulation but larger footprint increases board area | Choose when tighter dynamic regulation is required and SOD-123 mounting is already standardized |
Compared with BZX38450-B3V9X, the BZX384-C3V9 trades accuracy for cost in non-critical references, while MMSZ4685T1G offers superior dynamic performance at the expense of size and leakage - making the BZX38450-B3V9X optimal for space- and current-constrained precision biasing.
Availability
BZX38450-B3V9X is available at Aetrix Electronics and suitable for portable sensor nodes, microcontroller reset circuits, and USB interface protection requiring stable component supply with guaranteed long-term continuity.
Supply support for BZX38450-B3V9X 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, serving automotive, industrial, and consumer markets with ISO/TS 16949-certified manufacturing.
The BZX38450 series belongs to Nexperia's precision low-current Zener portfolio, engineered specifically for battery-powered and space-constrained applications demanding tight voltage tolerance, ultra-low leakage, and robust SMD manufacturability.
FAQ
What is the maximum continuous reverse power dissipation for BZX38450-B3V9X at 70 °C ambient?
At 70 °C ambient, derated power dissipation is 210 mW, calculated using the 300 mW rating at 25 °C and thermal resistance of 415 K/W. This assumes standard FR4 PCB mounting with single-sided 1 oz copper; forced airflow or thermal vias can extend usable power.
Can BZX38450-B3V9X be used in forward conduction mode as a signal diode?
Yes - its forward voltage is rated at ≤0.9 V at 10 mA, and it supports up to 250 mA continuous forward current. However, it lacks optimized fast-recovery characteristics; use only in low-speed clamping or biasing, not in switching or RF paths.
How does the −2.7 mV/K temperature coefficient affect regulation stability over −40 °C to +85 °C?
Over that range, total VZ drift is approximately ±135 mV (−2.7 mV/K × 50 K), resulting in a worst-case regulation band of 3.765 V to 4.035 V. This is acceptable for non-precision references but requires compensation in metrology-grade designs.
Is the SOD323 package compatible with standard reflow profiles for lead-free soldering?
Yes - Nexperia specifies compatibility with IPC/JEDEC J-STD-020D reflow profiles. Peak temperature must not exceed 260 °C for ≤30 seconds, with ramp rates ≤3 °C/s pre-peak; Figure 10 in the datasheet provides exact solder land dimensions and paste volume guidance.
BZX38450-B3V9X Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX38450
- Package/Case:
- SC-76, SOD-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 3.9 V
- Tolerance:
- ±2%
- Power - Max:
- 300 mW
- Impedance (Max) (Zzt):
- 95 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 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:
- SOD-323
BZX38450-B3V9X FAQ
1.How can I place an order for BZX38450-B3V9X through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX38450-B3V9X 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-B3V9X reliable?
The price and inventory of BZX38450-B3V9X are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX38450-B3V9X is usually 5 days.
3.What payment methods are accepted for BZX38450-B3V9X?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX38450-B3V9X transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX38450-B3V9X?
BZX38450-B3V9X orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX38450-B3V9X 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-B3V9X?
For technical support, including BZX38450-B3V9X datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX38450-B3V9X requirements.
6.How does Aetrix verify that BZX38450-B3V9X is sourced from the original manufacturer or authorized distributors?
All BZX38450-B3V9X 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-B3V9X meets industry standards.
7.What is the process for return or replacement of BZX38450-B3V9X?
All BZX38450-B3V9X units undergo pre-shipment inspection (PSI). If there is an issue with BZX38450-B3V9X, 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-B3V9X part is unused and in its original packaging.
Return procedure for BZX38450-B3V9X:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX38450-B3V9X 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…
