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onsemi SZMMSZ3V9T1G
- Part No.:
- SZMMSZ3V9T1G
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- SOD-123
- Datasheet:
-
SZMMSZ3V9T1G.pdf
- Description:
- DIODE ZENER 3.9V 500MW SOD123
- Quantity:
- Payment:
- Shipping:
Inventory:10,145
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Product details
Overview
SZMMSZ3V9T1G from onsemi is a 3.9 V ±5% Zener voltage regulator diode in SOD−123 package, rated for 500 mW power dissipation at 75°C, with 90 Ω dynamic impedance at 5 mA test current and 3 μA max reverse leakage at 1 V reverse bias - used for precision voltage reference and overvoltage protection in automotive power rails.
For engineers reviewing the SZMMSZ3V9T1G datasheet, pinout, applications, or equivalent options, key selection criteria include Zener tolerance (±5%), thermal resistance (340°C/W), AEC−Q101 qualification, ESD rating (>16 kV HBM), and Pb−free SOD−123 packaging for high-density automated assembly.
Technical Context
This device operates as a two-terminal shunt regulator, maintaining stable output voltage across variable load currents by conducting excess current to ground when input exceeds 3.9 V nominal. It features a temperature coefficient of approximately +2.9 mV/°C near its nominal Zener voltage, enabling predictable drift compensation in bias networks.
Designed for surface-mount use on FR−4/FR−5 PCBs, it delivers specified regulation under pulsed (1 ms) and steady-state conditions, with junction-to-ambient thermal resistance of 340°C/W and maximum junction temperature of +150°C - supporting operation in under-hood automotive environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 3.71–4.10 V @ IZT = 5 mA; ensures stable 3.9 V reference with ±5% tolerance for low-voltage rail monitoring |
| Power Dissipation (PD) | 500 mW @ TL = 75°C; supports continuous regulation in compact automotive modules without forced cooling |
| Zener Impedance (ZZT) | 90 Ω max @ IZT = 5 mA; limits output voltage variation under dynamic load transients |
| Reverse Leakage (IR) | 3 μA max @ VR = 1 V; minimizes quiescent current in battery-backed circuits |
| ESD Rating | Class 3 (>16 kV) per HBM; withstands handling and board-level electrostatic discharge without parameter shift |
| Junction Temp Range | −55°C to +150°C; enables deployment in engine control units and ADAS sensor interfaces |
Pinout & Package
Package: SOD−123 (Case 425), surface-mount plastic case with cathode band marking; dimensions 1.60 × 2.69 × 1.16 mm; UL 94 V−0 flammability rating; Pb−free and RoHS compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Banded End) | Cathode | Connected to regulated voltage node; conducts current into device during Zener breakdown |
| 2 (Non-banded End) | Anode | Connected to circuit ground or lower-potential reference; completes shunt regulation path |
Key Features
| Feature | Design Value |
|---|---|
| AEC−Q101 Qualified | Validated for automotive applications including powertrain and body electronics per stress test requirements |
| Small SOD−123 Footprint | Enables placement in space-constrained locations such as camera modules and radar front-ends |
| High ESD Robustness | Withstands >16 kV human-body-model discharge without parameter degradation or failure |
| Pb−Free Construction | Complies with global environmental regulations and reflow soldering profiles up to 260°C for 10 seconds |
Applications
| Automotive Engine Control Unit (ECU) | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Stabilizing 5 V microcontroller supply rail against alternator ripple and load dump transients. IC Role / Device Role / Timing Role: Shunt voltage reference and transient clamp protecting LDO input stage. Use Value: Maintains 3.9 V reference within ±5% across −40°C to +125°C ambient, reducing need for external trimming. | Use Scenario: Providing precise bias voltage for bridge amplifier inputs in pressure transducers. IC Role / Device Role / Timing Role: Low-drift DC reference source for analog front-end gain-setting networks. Use Value: Temperature coefficient of +2.9 mV/°C allows predictable offset compensation in closed-loop calibration. |
| Consumer USB-C Power Delivery Monitor | Medical Infusion Pump Power Supervision |
Use Scenario: Detecting overvoltage events on 3.3 V system bus during USB PD negotiation faults. IC Role / Device Role / Timing Role: Fast-response overvoltage protector clamping fault energy before downstream IC damage. Use Value: 90 Ω Zener impedance ensures sub-100 ns response to 10 V transients, meeting IEC 61000-4-5 Level 3 immunity. | Use Scenario: Monitoring battery backup voltage integrity in Class II medical devices with isolated power supplies. IC Role / Device Role / Timing Role: Low-leakage (3 μA max) voltage threshold detector for brown-out warning logic. Use Value: Enables >10-year shelf life in standby mode while maintaining accurate 3.9 V trip point across storage temperature range. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MMSZ3V9T1G | No SZ prefix; not AEC−Q101 qualified; identical electrical specs and SOD−123 package | Intended for industrial/commercial use only; lacks automotive change control documentation | Select when AEC−Q101 compliance is not required and cost sensitivity outweighs qualification needs |
| BZX384-B3V9,115 | Higher Zener impedance (120 Ω max); 250 mW power rating; SOD-323 package (smaller footprint) | Lower power handling limits use in sustained overvoltage clamping; tighter layout constraints | Select when board space is critical and peak surge energy remains below 0.25 J |
Compared with MMSZ3V9T1G and BZX384-B3V9,115, the SZMMSZ3V9T1G provides automotive-grade reliability with identical regulation performance and higher power margin, making it optimal for safety-critical voltage supervision where long-term parametric stability is mandated.
Availability
SZMMSZ3V9T1G is available at Aetrix Electronics and suitable for automotive ECU designs, industrial sensor nodes, and medical power supervision systems requiring stable component supply with full traceability and lifecycle management.
Supply support for SZMMSZ3V9T1G 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
onsemi (Semiconductor Components Industries, LLC) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
The MMSZxxxT1G/SZMMSZxxxT1G series was developed specifically for high-reliability voltage reference and protection in automotive electronics, emphasizing AEC−Q101 qualification, robust thermal performance, and compatibility with automated SMT assembly lines.
FAQ
What is the Zener voltage tolerance of SZMMSZ3V9T1G?
The SZMMSZ3V9T1G has a nominal Zener voltage of 3.9 V with a tolerance of ±5%, meaning the actual measured voltage falls between 3.71 V and 4.10 V when tested at 5 mA Zener current and 25°C ambient temperature. This tolerance is guaranteed per the onsemi datasheet revision 13 and applies across the full operating temperature range.
Is SZMMSZ3V9T1G suitable for automotive applications?
Yes, SZMMSZ3V9T1G is AEC−Q101 qualified and PPAP capable, with explicit design validation for automotive use cases including engine control, body electronics, and ADAS subsystems. The "SZ" prefix denotes compliance with automotive-specific site and change control requirements, distinguishing it from commercial-grade MMSZ3V9T1G variants.
What is the maximum reverse leakage current for SZMMSZ3V9T1G?
The maximum reverse leakage current for SZMMSZ3V9T1G is 3 μA at a reverse voltage of 1 V and ambient temperature of 25°C. At higher reverse voltages - such as 3.0 V - leakage remains below 10 μA, ensuring minimal parasitic loading in low-power monitoring circuits.
Does SZMMSZ3V9T1G have Pb−free construction?
Yes, SZMMSZ3V9T1G is Pb−free and RoHS compliant, with "G" suffix indicating lead-free termination and compatibility with standard reflow soldering profiles up to 260°C for 10 seconds. The SOD−123 package uses corrosion-resistant, easily solderable finish per onsemi's manufacturing specifications.
What is the thermal resistance of SZMMSZ3V9T1G?
The thermal resistance from junction-to-ambient (RJA) for SZMMSZ3V9T1G is 340°C/W when mounted on FR−5 board, and junction-to-lead (RJL) is 150°C/W. These values define the device's ability to dissipate heat under steady-state conditions and inform derating curves for operation above 75°C board temperature.
SZMMSZ3V9T1G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- SOD-123
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 3.9 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 90 Ohms
- Current - Reverse Leakage @ Vr:
- 3 µA @ 1 V
- Voltage - Forward (Vf) (Max) @ If:
- 900 mV @ 10 mA
- Operating Temperature:
- -55°C ~ 150°C
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOD-123
SZMMSZ3V9T1G FAQ
1.How can I place an order for SZMMSZ3V9T1G through Aetrix?
Please submit a Request for Quotation (RFQ) for SZMMSZ3V9T1G 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 SZMMSZ3V9T1G reliable?
The price and inventory of SZMMSZ3V9T1G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SZMMSZ3V9T1G is usually 5 days.
3.What payment methods are accepted for SZMMSZ3V9T1G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SZMMSZ3V9T1G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SZMMSZ3V9T1G?
SZMMSZ3V9T1G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SZMMSZ3V9T1G 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 SZMMSZ3V9T1G?
For technical support, including SZMMSZ3V9T1G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SZMMSZ3V9T1G requirements.
6.How does Aetrix verify that SZMMSZ3V9T1G is sourced from the original manufacturer or authorized distributors?
All SZMMSZ3V9T1G 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 SZMMSZ3V9T1G meets industry standards.
7.What is the process for return or replacement of SZMMSZ3V9T1G?
All SZMMSZ3V9T1G units undergo pre-shipment inspection (PSI). If there is an issue with SZMMSZ3V9T1G, 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 SZMMSZ3V9T1G part is unused and in its original packaging.
Return procedure for SZMMSZ3V9T1G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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