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onsemi SA33AG
- Part No.:
- SA33AG
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-204AC, DO-15, Axial
- Datasheet:
-
SA33AG.pdf
- Description:
- TVS DIODE 33VWM 53.3VC AXIAL
- Quantity:
- Payment:
- Shipping:
Inventory:4,184
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Product details
Overview
SA33AG from onsemi is a unidirectional 500 W peak power MiniMOSORB Zener transient voltage suppressor (TVS) designed for clamping high-energy transients in DC power rails and signal lines. It features a 33 V working peak reverse voltage (VRWM), 53.3 V maximum clamping voltage at 9.4 A peak pulse current, <1 µA leakage at VRWM, and sub-1 ns response time. It is used in industrial power supplies, medical equipment surge protection, and communication interface line protection.
For engineers reviewing the SA33AG datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage margin relative to system operating voltage, peak pulse current capability under 1 ms waveform, UL 497B certification for isolated loop circuits, and axial leaded Surmetic package thermal performance under repetitive surge conditions.
Technical Context
The SA33AG operates as a unidirectional Zener-based TVS diode, conducting only during reverse overvoltage events above its breakdown threshold. Its clamping behavior is defined by a 36.7–40.6 V breakdown voltage range at 1 mA test current and a guaranteed maximum clamping voltage of 53.3 V at 9.4 A IPP (1 ms pulse).
It delivers 500 W nonrepetitive peak power dissipation per UL-defined 1 ms waveform, with thermal resistance of 33.3 °C/W (junction-to-lead) and steady-state power rating of 3.0 W at 25°C ambient. The device meets Class 3 ESD immunity (>16 kV HBM) and is UL 497B recognized for isolated loop circuit protection.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 33 V - Maximum continuous reverse operating voltage before clamping begins; sets minimum system rail voltage compatibility. |
| VBR (min/typ/max) | 36.7 / 38.65 / 40.6 V @ 1 mA - Confirmed Zener breakdown range; determines actual turn-on threshold in production. |
| VC @ IPP | 53.3 V @ 9.4 A - Maximum clamped voltage during 1 ms transient; defines worst-case stress on downstream ICs. |
| IPP | 9.4 A - Peak pulse current supported at rated clamping voltage; correlates to IEC 61000-4-5 Level 3 surge capability. |
| Leakage Current | <1 µA @ 33 V - Negligible standby power loss and minimal impact on high-impedance sensing circuits. |
| Response Time | <1 ns - Fast enough to protect CMOS inputs and high-speed interfaces against EFT/burst transients. |
| UL Recognition | UL 497B (QVGQ2, File #E210057) - Validated for use in telecom and industrial isolated loop protection applications. |
Pinout & Package
SA33AG is housed in an axial-leaded Surmetic plastic package (Case 59AA), with cathode identified by a polarity band. Leads are tin-plated, solderable at 260°C for 10 seconds at 1/16 inch from case.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Reference node for reverse-biased operation | Connected to system ground or low-side return path; must be low-impedance to handle surge return current. |
| Cathode | Transient clamping node | Connected to protected line (e.g., +3.3 V rail); conducts during overvoltage to clamp voltage to ≤53.3 V. |
Key Features
| Feature | Design Value |
|---|---|
| 500 W peak pulse power | Supports robust protection against IEC 61000-4-5 combination wave surges up to 4 kV/2 Ω without degradation. |
| UL 497B recognition | Validated for safety-critical isolated loop circuits in medical and telecom infrastructure-no additional certification required. |
| Class 3 ESD immunity | Withstands >16 kV human-body-model discharge, eliminating need for supplemental ESD diodes in front-end interfaces. |
| Pb-free Surmetic package | RoHS-compliant axial construction with void-free molding and corrosion-resistant finish for long-term reliability in humid environments. |
| Low zener impedance | Ensures stable clamping across temperature and aging, critical for consistent protection in 24/7 industrial systems. |
Applications
| Industrial Power Supply Input Protection | Medical Equipment Signal Line Clamping |
|---|---|
|
Use Scenario: Protecting 24 V DC input rails in programmable logic controllers (PLCs) against load dump and inductive switching transients. IC Role / Device Role / Timing Role: Standoff TVS diode placed between input rail and chassis ground, absorbing energy before it reaches upstream regulators and microcontrollers. Use Value: Limits rail voltage to ≤53.3 V during 9.4 A surges, preventing latch-up or permanent damage to 36 V-rated DC/DC converters. |
Use Scenario: Safeguarding analog sensor inputs (e.g., thermocouple or pressure transducer lines) in FDA-cleared patient monitors. IC Role / Device Role / Timing Role: Unidirectional clamping element on low-voltage signal paths referenced to isolated earth, compliant with UL 497B requirements. Use Value: Maintains signal integrity under EFT bursts while satisfying regulatory isolation barrier testing-no redesign needed for 510(k) submission. |
| Telecom Interface Surge Suppression | Process Control Fieldbus Protection |
|
Use Scenario: Front-end protection for RS-485 transceivers in outdoor base station backhaul links exposed to lightning-induced surges. IC Role / Device Role / Timing Role: Primary transient suppressor on differential bus lines, coordinated with common-mode chokes and secondary TVS arrays. Use Value: Clamps common-mode transients to safe levels within <1 ns, preserving data integrity during 10/700 µs lightning surges per ITU-T K.21. |
Use Scenario: Protecting HART or Foundation Fieldbus segments in hazardous-area process transmitters installed in oil refineries. IC Role / Device Role / Timing Role: Intrinsically safe-compatible TVS on powered fieldbus pairs, selected for low leakage (<1 µA) to avoid interfering with 4–20 mA loop accuracy. Use Value: Enables certified IS barrier design without derating loop voltage margin-verified via UL 497B endurance conditioning tests. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ33A | Same VRWM (33 V) and VC (53.3 V), but SMC package (surface-mount), lower IPP (9.2 A), no UL 497B listing. | Preferred for automated PCB assembly where board space is constrained; unsuitable for UL-certified isolated loop designs. | Select SMAJ33A only when surface-mount layout and RoHS compliance are prioritized over safety certification and axial mechanical robustness. |
| P6SMB33A | Identical electrical specs (VRWM = 33 V, VC = 53.3 V, IPP = 9.4 A), DO-214AA package, UL 497B recognized, but higher leakage (5 µA @ VRWM). | Valid for same UL-certified applications, but higher leakage may affect precision 4–20 mA loop accuracy in field instruments. | Choose P6SMB33A when footprint compatibility with existing SMC layouts is required and leakage sensitivity is not critical. |
Compared with SMAJ33A and P6SMB33A, SA33AG provides axial-leaded mechanical stability for high-vibration environments, guaranteed <1 µA leakage for precision analog systems, and full UL 497B validation-making it the preferred choice for medical and industrial safety-critical deployments.
Availability
SA33AG is available at Aetrix Electronics and suitable for industrial power supplies, medical diagnostic equipment, and telecom infrastructure requiring stable component supply with full safety certification traceability.
Supply support for SA33AG 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 (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensors, and connectivity solutions for automotive, industrial, and cloud power applications.
The SA5.0A Series-including SA33AG-is part of onsemi's MiniMOSORB TVS portfolio, engineered specifically for high-reliability transient suppression in safety-certified industrial and medical systems where UL 497B compliance and repeatable clamping performance are mandatory.
FAQ
What is the maximum clamping voltage of the SA33AG under standard test conditions?
The SA33AG has a maximum clamping voltage (VC) of 53.3 V when subjected to its rated peak pulse current of 9.4 A with a 1 ms exponential waveform (per Figure 4). This value is guaranteed across temperature and production lot, ensuring predictable protection margins for downstream 36 V-rated components in the SA33AG circuit design.
Does the SA33AG meet UL 497B requirements for isolated loop protection?
Yes, the SA33AG is explicitly included in onsemi's UL 497B recognition (File #E210057, QVGQ2 category) for protector-class devices. This certification covers endurance conditioning, dielectric withstand, and strike voltage breakdown testing-validating its use in isolated loop circuits such as those found in medical telemetry and industrial fieldbus isolators using the SA33AG.
What is the leakage current specification for SA33AG at its working voltage?
The SA33AG specifies a maximum reverse leakage current of 1 µA at its working peak reverse voltage of 33 V (VRWM), measured at 25°C. This ultra-low leakage ensures minimal loading on high-impedance sensor interfaces and preserves accuracy in 4–20 mA current loops where even microamp-level errors affect calibration-critical in SA33AG-based process instrumentation.
Is the SA33AG compatible with lead-free reflow soldering processes?
The SA33AG is supplied in a Pb-free Surmetic axial package (Case 59AA) qualified for wave and hand soldering at 260°C for 10 seconds at 1/16 inch from the case. While not intended for reflow (due to axial lead geometry), it supports standard lead-free assembly practices-ensuring reliable interconnects in SA33AG-equipped industrial control modules without compromising RoHS compliance.
How does the SA33AG's thermal resistance affect its surge handling capability?
With a junction-to-lead thermal resistance (RJL) of 33.3 °C/W, the SA33AG efficiently transfers heat from the silicon junction to the leads during transient events. This enables sustained 500 W peak power dissipation for 1 ms pulses and supports repeated surge duty cycles when leads are properly heatsunk-key for SA33AG deployment in motor drive power supplies subject to frequent commutation spikes.
SA33AG Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-204AC, DO-15, Axial
- Series:
- MiniMosorb™
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 33V
- Voltage - Breakdown (Min):
- 36.7V
- Voltage - Clamping (Max) @ Ipp:
- 53.3V
- Current - Peak Pulse (10/1000µs):
- 9.4A
- Power - Peak Pulse:
- 500W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- Axial
SA33AG FAQ
1.How can I place an order for SA33AG through Aetrix?
Please submit a Request for Quotation (RFQ) for SA33AG 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 SA33AG reliable?
The price and inventory of SA33AG are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SA33AG is usually 5 days.
3.What payment methods are accepted for SA33AG?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SA33AG transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SA33AG?
SA33AG orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SA33AG 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 SA33AG?
For technical support, including SA33AG datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SA33AG requirements.
6.How does Aetrix verify that SA33AG is sourced from the original manufacturer or authorized distributors?
All SA33AG 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 SA33AG meets industry standards.
7.What is the process for return or replacement of SA33AG?
All SA33AG units undergo pre-shipment inspection (PSI). If there is an issue with SA33AG, 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 SA33AG part is unused and in its original packaging.
Return procedure for SA33AG:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SA33AG Tags
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ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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ESD5Z3.3T1G
onsemi
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D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
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ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
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DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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D5V0L1B2WS-7
Diodes Incorporated
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