My Inquiry
My Account
Nexperia USA Inc. BZX384-A12-QX
- Part No.:
- BZX384-A12-QX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-76, SOD-323
- Datasheet:
-
BZX384-A12-QX.pdf
- Description:
- DIODE ZENER 12V 300MW SOD323
- Quantity:
- Payment:
- Shipping:
Inventory:9,321
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BZX384-A12-QX from Nexperia is a ±1 % tolerance Zener voltage regulator diode in SOD323 (SC-76) package, rated for 12 V nominal breakdown voltage at 5 mA, 300 mW total power dissipation, and qualified to AEC-Q101 for automotive voltage reference and overvoltage protection circuits.
For engineers reviewing the BZX384-A12-QX datasheet, BZX384-A12-QX pinout, BZX384-A12-QX application, or BZX384-A12-QX equivalent, this page delivers verified electrical parameters, thermal behavior, automotive qualification status, and real-world design implications for precision biasing and transient clamping in constrained PCB layouts.
Technical Context
This Zener diode operates in reverse-biased breakdown mode with a tightly controlled 11.88–12.12 V tolerance window at IZ = 5 mA, exhibiting a temperature coefficient of +0.1 mV/K and differential resistance ≤150 Ω. Its low 415 K/W junction-to-ambient thermal resistance enables stable regulation under ambient temperatures from –65 °C to +150 °C.
Designed for surface-mount reliability, it supports non-repetitive peak reverse power dissipation up to 40 W (100 μs pulse), reverse current <25 μA at VR = 10.8 V, and forward voltage ≤0.9 V at IF = 10 mA - enabling robust operation in both regulation and clamping configurations.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Breakdown Voltage (VZ) | 11.88–12.12 V at IZ = 5 mA - ensures precise 12 V reference within ±1 % for analog sensing and supply rail stabilization. |
| Power Dissipation (Ptot) | 300 mW at Tamb ≤ 25 °C - defines maximum continuous DC power handling on standard FR4 PCB with single-sided copper. |
| Differential Resistance (rdif) | ≤150 Ω - limits output voltage variation under load current changes, critical for low-drift reference applications. |
| Reverse Current (IR) | <25 μA at VR = 10.8 V - guarantees minimal leakage before breakdown, essential for battery-powered standby circuits. |
| Non-repetitive Peak Power (PZSM) | 40 W (100 μs pulse) - enables transient surge suppression without device failure in automotive load-dump scenarios. |
| Junction Temperature (Tj) | –65 °C to +150 °C - supports operation across full automotive under-hood and cabin environments. |
| AEC-Q101 Qualified | Yes - validated for automotive discrete semiconductor stress testing, including HTGB, HTRB, and temperature cycling. |
Pinout & Package
Package: SOD323 (SC-76), 2-pin surface-mount plastic package with cathode marked by a bar on the body. Dimensions: 1.8 × 1.35 × 0.45 mm (L × W × H).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Cathode (K) | Connected to regulated output node; polarity marker (bar) aligns with this terminal for correct PCB orientation. |
| 2 | Anode (A) | Connected to ground or lower-potential rail; reverse-bias configuration requires anode at lower voltage than cathode. |
Key Features
| Feature | Design Value |
|---|---|
| ±1 % voltage tolerance | Enables high-accuracy voltage references without external trimming, reducing BOM count in sensor signal conditioning. |
| AEC-Q101 qualification | Validates suitability for automotive powertrain, body control, and ADAS modules requiring long-term reliability under thermal and mechanical stress. |
| SOD323 footprint | 0.65 mm pitch and 1.35 mm width allow dense placement in space-constrained modules like ECU sub-assemblies and LED drivers. |
| 40 W surge capability | Withstands ISO 7637-2 Pulse 1/2a/5a transients without derating, eliminating need for parallel TVS in many 12 V vehicle systems. |
| Low 25 μA max reverse leakage | Minimizes quiescent current draw in always-on circuits such as CAN bus termination biasing and microcontroller reset supervision. |
Applications
| Automotive ECU Voltage Reference | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Providing stable 12 V reference for ADC biasing and op-amp feedback networks in engine control units. IC Role / Device Role / Timing Role: Zener diode operating in reverse breakdown to maintain fixed reference potential independent of supply ripple. Use Value: ±1 % tolerance and +0.1 mV/K TC ensure <±15 mV drift over –40 °C to +125 °C, meeting ASIL-B functional safety margin requirements. |
Use Scenario: Biasing bridge sensors and RTD interfaces in programmable logic controllers and process transmitters. IC Role / Device Role / Timing Role: Precision shunt regulator establishing known excitation voltage for ratiometric measurements. Use Value: 150 Ω differential resistance minimizes loading error when sourcing 1–5 mA to 350 Ω sensor elements. |
| USB-C Port Overvoltage Protection | Smart Lighting Driver Feedback Clamp |
Use Scenario: Clamping VBUS line against 20 V transients during hot-plug events in automotive infotainment USB hubs. IC Role / Device Role / Timing Role: Fast-acting shunt clamp activated above 12.12 V to divert surge energy before downstream IC damage. Use Value: 40 W non-repetitive peak power rating absorbs 100 μs pulses per IEC 61000-4-5 Level 3 without degradation. |
Use Scenario: Stabilizing feedback node voltage in constant-current LED drivers to prevent thermal runaway during dimming cycles. IC Role / Device Role / Timing Role: Shunt regulator holding optocoupler input voltage at 12 V to maintain accurate current regulation loop gain. Use Value: Low 25 μA reverse leakage avoids false triggering of feedback comparators during PWM off-states. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX384-B12-Q | ±2 % tolerance (11.8–12.2 V), higher max reverse current (30 μA at 10.8 V) | Acceptable where 12 V reference stability <±200 mV suffices, e.g., non-critical power sequencing. | Select for cost-sensitive industrial controls where AEC-Q101 is not mandated. |
| MMSZ4687T1G | ±5 % tolerance (11.4–12.6 V), 500 mW Ptot, SOD-123 package (larger footprint) | Higher power handling but looser tolerance; suitable for general-purpose clamping with thermal margin. | Choose when board layout allows larger SOD-123 and ±5 % accuracy is acceptable for bulk protection. |
Compared with BZX384-B12-Q and MMSZ4687T1G, the BZX384-A12-QX offers the tightest voltage tolerance and smallest footprint while maintaining AEC-Q101 compliance - making it optimal for space-constrained automotive reference designs where accuracy and qualification are non-negotiable.
Availability
BZX384-A12-QX is available at Aetrix Electronics and suitable for automotive ECUs, industrial sensor interfaces, USB-C overvoltage protection, and smart lighting driver feedback circuits requiring stable component supply with guaranteed long-term manufacturability.
Supply support for BZX384-A12-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 advanced packaging technologies.
The BZX384-Q series belongs to Nexperia's automotive-grade Zener diode product line, engineered specifically for precision voltage reference and transient suppression in harsh-environment electronic control units and sensor subsystems.
FAQ
What is the maximum continuous reverse current this diode can sustain at 12 V?
The BZX384-A12-QX is not rated for continuous reverse conduction at its nominal Zener voltage. At VR = 10.8 V (90 % of VZ), reverse current is guaranteed ≤25 μA. Sustained operation at or above 12 V must be limited by series resistance to keep power dissipation ≤300 mW - typically restricting average current to ≤25 mA with adequate PCB copper area.
Does the marking code '33' correspond exclusively to BZX384-A12-Q?
Yes - per Table 4 of the datasheet, marking code '33' is assigned solely to BZX384-A12-Q. This unambiguous one-to-one mapping enables automated optical inspection (AOI) and traceability verification during SMT assembly without cross-reference ambiguity.
How does thermal resistance impact regulation accuracy in a compact PCB layout?
With Rth(j-a) = 415 K/W on standard FR4, a 300 mW dissipation raises junction temperature by ~125 °C above ambient. Since VZ has +0.1 mV/K TC, this causes ~12.5 mV positive shift - a critical factor in high-precision references. Using thermal vias or increased copper pour reduces Rth and stabilizes regulation.
Can this diode replace a 1N4742A in an existing design?
Electrically, yes - both are 12 V Zeners. However, BZX384-A12-QX uses SOD323 (0.65 mm pitch) versus 1N4742A's DO-41 (5.3 mm lead spacing). The footprint change requires PCB redesign. Also, BZX384-A12-QX's tighter ±1 % tolerance and AEC-Q101 qualification may necessitate revalidation in automotive applications.
BZX384-A12-QX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BZX384-Q
- Package/Case:
- SC-76, SOD-323
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 12 V
- Tolerance:
- ±1%
- Power - Max:
- 300 mW
- Impedance (Max) (Zzt):
- 25 Ohms
- Current - Reverse Leakage @ Vr:
- 100 nA @ 8 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.1 V @ 100 mA
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOD-323
BZX384-A12-QX FAQ
1.How can I place an order for BZX384-A12-QX through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX384-A12-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 BZX384-A12-QX reliable?
The price and inventory of BZX384-A12-QX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX384-A12-QX is usually 5 days.
3.What payment methods are accepted for BZX384-A12-QX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX384-A12-QX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX384-A12-QX?
BZX384-A12-QX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX384-A12-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 BZX384-A12-QX?
For technical support, including BZX384-A12-QX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX384-A12-QX requirements.
6.How does Aetrix verify that BZX384-A12-QX is sourced from the original manufacturer or authorized distributors?
All BZX384-A12-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 BZX384-A12-QX meets industry standards.
7.What is the process for return or replacement of BZX384-A12-QX?
All BZX384-A12-QX units undergo pre-shipment inspection (PSI). If there is an issue with BZX384-A12-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 BZX384-A12-QX part is unused and in its original packaging.
Return procedure for BZX384-A12-QX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX384-A12-QX 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…
