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onsemi SZMMSZ33ET1G
- Part No.:
- SZMMSZ33ET1G
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- SOD-123
- Datasheet:
-
SZMMSZ33ET1G.pdf
- Description:
- DIODE ZENER 33V 500MW SOD123
- Quantity:
- Payment:
- Shipping:
Inventory:10,395
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Product details
Overview
SZMMSZ33ET1G from onsemi is a 33 V ±5% Zener voltage regulator diode in SOD-123 surface-mount package, rated for 500 mW power dissipation at 75 °C on FR-5 board, with 80 Ω maximum dynamic impedance at 5 mA test current and 0.05 µA reverse leakage at 23.1 V. It serves as a precision voltage reference or overvoltage clamp in automotive power rails and industrial sensor signal conditioning circuits.
For engineers reviewing the SZMMSZ33ET1G datasheet, pinout, applications, or equivalent options, key selection criteria include its AEC-Q101 qualification, 16 kV HBM ESD rating, 225 W peak surge capability (8 × 20 µs), and stable temperature coefficient near zero crossing (~0.5 mV/°C at 33 V) - critical for automotive body control modules and battery management systems requiring long-term voltage stability.
Technical Context
This device operates in reverse-biased Zener breakdown mode, delivering regulated voltage across its cathode-anode terminals when reverse current exceeds the knee threshold. Its 33 V nominal Zener voltage is specified at IZT = 5 mA with ±5% tolerance, and dynamic impedance is measured at 1 kHz AC signal superimposed on DC bias per JEDEC JESD24-A.
The SOD-123 package enables automated placement in high-density PCB layouts while maintaining thermal resistance of 340 °C/W (junction-to-ambient) and 150 °C/W (junction-to-lead). It supports reflow soldering up to 260 °C for 10 seconds and meets UL 94 V-0 flammability rating.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 33 V nominal, ±5% tolerance (31.35 V to 34.65 V) at IZT = 5 mA - defines precise clamping level for overvoltage protection |
| Power Dissipation (PD) | 500 mW on FR-5 board at TL = 75 °C - sets continuous operating limit without derating in standard PCB environments |
| Zener Impedance (ZZT) | 80 Ω max at IZT = 5 mA, 1 kHz - determines regulation stiffness under varying load current |
| Reverse Leakage (IR) | 0.05 µA max at VR = 23.1 V - ensures minimal standby current in always-on automotive modules |
| Peak Surge Power (PPK) | 225 W for 8 × 20 µs pulse - withstands ISO 7637-2 transient pulses in 12 V vehicle systems |
| ESD Rating | Class 3 (>16 kV) per Human Body Model - eliminates need for external ESD protection in exposed I/O lines |
| Temperature Range | −55 °C to +150 °C junction/storage - qualified for under-hood automotive locations and industrial motor drives |
Pinout & Package
SOD-123 plastic surface-mount package (1.60 × 2.69 × 1.16 mm), void-free thermosetting case with corrosion-resistant finish; polarity indicated by cathode band; lead-free (Pb-Free) construction.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Cathode) | Zener voltage reference node | Connected to regulated output or protected circuit node; carries reverse current during clamping |
| 2 (Anode) | Reference ground return path | Bonded to PCB ground plane; completes current loop during Zener conduction; must maintain low-impedance path |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 Qualified | Validated for automotive applications including engine control units and ADAS power domains |
| High ESD Robustness | 16 kV HBM rating eliminates external TVS in cost-sensitive CAN/LIN bus termination networks |
| Precision Voltage Regulation | ±5% tolerance at 33 V enables direct replacement of legacy 33 V references without recalibration |
| Thermal Stability | Near-zero temperature coefficient region around 33 V minimizes drift over −40 °C to +125 °C ambient |
| Automated Assembly Optimized | SOD-123 footprint matches industry-standard pick-and-place tooling and reflow profiles |
Applications
| Automotive Body Control Module | Industrial Sensor Signal Conditioning |
|---|---|
Use Scenario: Regulating 33 V supply rail for microcontroller I/O buffers and LIN transceivers in door module ECUs. IC Role / Device Role / Timing Role: Voltage reference and transient suppressor protecting 3.3 V logic inputs from load-dump spikes. Use Value: Maintains stable 33 V reference under ISO 16750-2 load-dump conditions while consuming <0.1 µA in sleep mode. |
Use Scenario: Clamping analog output of 4–20 mA current-loop pressure sensors to prevent ADC overrange. IC Role / Device Role / Timing Role: Precision shunt regulator establishing upper voltage limit before op-amp input stage. Use Value: Limits sensor output to ≤34.65 V with <80 Ω dynamic impedance, preserving linearity within 0.1% full-scale error. |
| Programmable Logic Controller Input Protection | DC-DC Converter Feedback Reference |
Use Scenario: Protecting 24 V digital input channels against field-wiring faults and inductive kickback in factory automation PLCs. IC Role / Device Role / Timing Role: Fast-acting overvoltage clamp placed between input terminal and optocoupler anode. Use Value: Responds within nanoseconds to 225 W surges, limiting voltage to 34.65 V and preventing optocoupler damage. |
Use Scenario: Providing stable 33 V reference for feedback divider network in isolated flyback converters powering industrial HMIs. IC Role / Device Role / Timing Role: Shunt voltage reference setting output voltage accuracy independent of primary-side controller drift. Use Value: Achieves ±1.5% output regulation over temperature due to matched TC characteristics with resistor dividers. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MMSZ33ET1G | No SZ prefix; not AEC-Q101 qualified; same electrical specs and SOD-123 package | Intended for commercial/industrial use only; lacks automotive traceability and PPAP documentation | Select when automotive qualification is unnecessary and cost sensitivity outweighs long-term supply assurance |
| BZX84-C33 | 33 V ±5%, 300 mW rating, SOT-23 package; higher ZZT (100 Ω), lower surge rating (100 W) | Smaller footprint but reduced power handling; unsuitable for ISO 7637-2 pulse immunity requirements | Choose only for space-constrained non-automotive designs where 500 mW continuous dissipation is not required |
Compared with MMSZ33ET1G and BZX84-C33, SZMMSZ33ET1G provides automotive-grade reliability, higher surge robustness, and identical regulation performance - making it the sole choice for safety-critical 12 V system nodes requiring AEC-Q101 compliance and 225 W transient immunity.
Availability
SZMMSZ33ET1G is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor interfaces, and programmable logic controller input protection requiring stable component supply across extended temperature ranges and high-reliability production cycles.
Supply support for SZMMSZ33ET1G 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 is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
SZMMSZxxxET1G series belongs to onsemi's AEC-Q101-qualified Zener regulator portfolio, engineered specifically for automotive subsystems demanding high transient immunity, low leakage, and long-term voltage stability under harsh thermal cycling.
FAQ
What is the Zener voltage tolerance and test condition for SZMMSZ33ET1G?
The SZMMSZ33ET1G has a nominal Zener voltage of 33 V with ±5% tolerance, measured at IZT = 5 mA with 1 ms pulse width. This yields a guaranteed range of 31.35 V to 34.65 V at 25 °C ambient, supporting precise voltage clamping in automotive and industrial designs where tight regulation is mandatory.
Is SZMMSZ33ET1G suitable for automotive applications?
Yes, SZMMSZ33ET1G is AEC-Q101 qualified and PPAP capable, with full traceability and process controls meeting automotive quality standards. Its −55 °C to +150 °C operating range, 16 kV HBM ESD rating, and 225 W surge capability make it appropriate for under-hood and chassis-mounted modules using the SZ prefix designation.
What is the maximum power dissipation of SZMMSZ33ET1G on a standard PCB?
SZMMSZ33ET1G delivers 500 mW total power dissipation on FR-5 board at lead temperature (TL) = 75 °C, derating linearly at 6.7 mW/°C above that point. At 25 °C ambient, thermal resistance is 340 °C/W junction-to-ambient, enabling reliable operation in compact, unventilated enclosures typical of automotive ECUs.
How does the dynamic impedance of SZMMSZ33ET1G affect voltage regulation accuracy?
SZMMSZ33ET1G exhibits ≤80 Ω dynamic impedance at IZT = 5 mA and 1 kHz, meaning a 1 mA change in Zener current causes ≤80 mV shift in regulated voltage. This low ZZT ensures minimal output variation under dynamic load conditions in feedback networks and precision reference circuits.
What packaging and marking format does SZMMSZ33ET1G use?
SZMMSZ33ET1G is supplied in Pb-free SOD-123 package (Case 425, Style 1), marked with "CP1" code and date code per onsemi's generic marking diagram. It ships in 3,000-unit tape-and-reel format, compatible with standard SMT assembly equipment and reflow profiles up to 260 °C for 10 seconds.
SZMMSZ33ET1G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- SOD-123
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 33 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 80 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 23.1 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
SZMMSZ33ET1G FAQ
1.How can I place an order for SZMMSZ33ET1G through Aetrix?
Please submit a Request for Quotation (RFQ) for SZMMSZ33ET1G 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 SZMMSZ33ET1G reliable?
The price and inventory of SZMMSZ33ET1G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SZMMSZ33ET1G is usually 5 days.
3.What payment methods are accepted for SZMMSZ33ET1G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SZMMSZ33ET1G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SZMMSZ33ET1G?
SZMMSZ33ET1G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SZMMSZ33ET1G 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 SZMMSZ33ET1G?
For technical support, including SZMMSZ33ET1G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SZMMSZ33ET1G requirements.
6.How does Aetrix verify that SZMMSZ33ET1G is sourced from the original manufacturer or authorized distributors?
All SZMMSZ33ET1G 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 SZMMSZ33ET1G meets industry standards.
7.What is the process for return or replacement of SZMMSZ33ET1G?
All SZMMSZ33ET1G units undergo pre-shipment inspection (PSI). If there is an issue with SZMMSZ33ET1G, 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 SZMMSZ33ET1G part is unused and in its original packaging.
Return procedure for SZMMSZ33ET1G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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