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onsemi SA12AG
- Part No.:
- SA12AG
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-204AC, DO-15, Axial
- Datasheet:
-
SA12AG.pdf
- Description:
- TVS DIODE 12VWM 19.9VC AXIAL
- Quantity:
- Payment:
- Shipping:
Inventory:5,890
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Product details
Overview
SA12AG 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 12 V working peak reverse voltage (VRWM), 19.9 V maximum clamping voltage at 25.1 A peak pulse current, <1 µA leakage at VRWM, and sub-1 ns response time. It is used in industrial power supplies and medical equipment input protection.
For engineers reviewing the SA12AG datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage margin relative to protected IC VDD, surge current capability under 1 ms pulses, UL 497B certification for isolated loop circuits, and axial leaded Surmetic package compatibility with through-hole assembly processes.
Technical Context
The SA12AG operates as a voltage-clamping device in parallel with sensitive circuitry, conducting only when transient voltage exceeds its breakdown threshold (13.3–14.7 V at 1 mA). Its low zener impedance and fast response ensure minimal overvoltage exposure during ESD or lightning-induced surges.
It is rated for 500 W nonrepetitive peak power per 1 ms pulse (Figure 4 waveform), derates linearly above 25°C ambient, and maintains stable breakdown voltage with a specified temperature coefficient. UL 497B recognition confirms compliance for isolated loop circuit protection in safety-critical systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 12 V - Maximum continuous reverse operating voltage before clamping begins; must exceed circuit's normal DC rail voltage. |
| VBR @ IT = 1 mA | 13.3–14.7 V - Confirmed breakdown range ensures predictable turn-on without premature conduction. |
| VC @ IPP = 25.1 A | 19.9 V - Clamped voltage seen by protected circuit during worst-case 500 W transient; defines overvoltage margin. |
| IPP | 25.1 A - Peak pulse current capability at 1 ms pulse width; determines survivability against IEC 61000-4-5 surge events. |
| IR @ VRWM | <1 µA - Negligible leakage at rated working voltage; avoids loading of high-impedance sensor or reference circuits. |
| Response Time | <1 ns - Enables suppression of fast-rising ESD transients (IEC 61000-4-2) before downstream ICs are damaged. |
| UL Recognition | UL 497B (QVGQ2, File #E210057) - Validated for use in isolated loop protectors, not just flammability-rated packaging. |
Pinout & Package
SA12AG uses an axial-leaded Surmetic plastic package (Case 59AA), with cathode indicated by a polarity band. Leads are tin-plated, solderable at 260°C for 10 seconds at 1/16″ from case. Mounting position is unrestricted.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side connection point | Connected to ground or lowest potential node in clamping configuration; carries full surge return current. |
| Cathode | High-side connection point | Connected to protected line (e.g., +12 V rail); polarity band identifies this terminal for correct orientation. |
Key Features
| Feature | Design Value |
|---|---|
| 500 W Peak Pulse Power | Supports robust protection against IEC 61000-4-5 Level 4 (4 kV/2 Ω) surges on 12 V DC inputs without failure. |
| UL 497B Recognition | Validated for use in certified isolated loop protectors-enables direct inclusion in safety-compliant industrial control designs. |
| ESD Rating >16 kV (HBM) | Withstands human-body-model ESD events common in handling and field operation without parameter shift or degradation. |
| Pb-Free Surmetic Package | RoHS-compliant axial lead construction with corrosion-resistant finish and verified solderability per J-STD-020. |
| Low Zener Impedance | Ensures tight clamping voltage window (VC − VBR ≈ 6.6 V), minimizing stress on downstream 12 V logic or analog ICs. |
Applications
| Industrial Power Supply Input Protection | Medical Equipment Signal Line Clamp |
|---|---|
Use Scenario: Protecting 12 V DC input stage of programmable logic controllers (PLCs) against load dump and inductive switching transients. IC Role / Device Role / Timing Role: Unidirectional shunt TVS placed between +12 V rail and chassis ground to clamp surges exceeding 12 V. Use Value: Limits transient voltage to ≤19.9 V, preserving integrity of upstream DC/DC converters and microcontroller power domains. |
Use Scenario: Safeguarding analog front-end inputs (e.g., ECG electrode leads) from ESD and defibrillator-induced transients. IC Role / Device Role / Timing Role: Low-capacitance (<100 pF) TVS mounted at connector interface to divert fast transients before reaching precision amplifiers. Use Value: Sub-1 ns response prevents amplifier saturation or latch-up during 15 kV HBM ESD events, maintaining diagnostic accuracy. |
| Communications Interface Surge Protection | Numerical Control System DC Bus Clamp |
Use Scenario: Shielding RS-485 transceiver VCC pins in factory automation gateways exposed to long cable runs. IC Role / Device Role / Timing Role: Standoff TVS connected from VCC to ground to absorb coupled surges from adjacent motor drives or relay coils. Use Value: 12 V VRWM matches typical RS-485 transceiver supply; 19.9 V clamping prevents overvoltage damage to internal LDOs and drivers. |
Use Scenario: Clamping 12 V auxiliary bus in CNC machine controllers subject to regenerative braking spikes. IC Role / Device Role / Timing Role: Parallel-connected TVS absorbing repetitive 50–100 A, 100 µs transients generated by servo drive feedback loops. Use Value: 500 W peak rating and 33.3 °C/W junction-to-lead thermal resistance enable reliable dissipation without thermal runaway. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ12A | Surface-mount SMA package (vs. axial); 200 W peak power; 23.2 V clamping at 21.2 A. | Limited to PCB space-constrained designs where through-hole mounting is impractical. | Choose SMAJ12A only if board layout prohibits axial components and surge energy remains ≤200 W. |
| P6SMB12A | Same axial package (DO-214AA), but 600 W peak power; 19.9 V clamping at 30.1 A; higher IR (5 µA). | Better suited for higher-energy transients but introduces greater leakage in ultra-low-power monitoring circuits. | Select P6SMB12A when system-level surge testing requires >500 W margin and leakage tolerance >1 µA is acceptable. |
Compared with SA12AG, SMAJ12A offers smaller footprint but reduced surge capacity and no UL 497B listing, while P6SMB12A delivers higher peak power and identical clamping voltage but trades off leakage performance-making SA12AG optimal for UL-certified, medium-energy 12 V rail protection with minimal leakage.
Availability
SA12AG is available at Aetrix Electronics and suitable for industrial power supplies, medical equipment interfaces, and communication system surge protection requiring stable component supply and long-term lifecycle support.
Supply support for SA12AG 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, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.
The SA12AG belongs to the SA5.0A Series MiniMOSORB TVS family, engineered specifically for high-reliability transient suppression in safety-critical industrial and medical systems requiring UL 497B certification and axial-leaded robustness.
FAQ
What is the maximum clamping voltage of the SA12AG under rated surge conditions?
The SA12AG exhibits a maximum clamping voltage (VC) of 19.9 V when subjected to its rated peak pulse current of 25.1 A (per 1 ms waveform). This value is measured per Figure 4 in the official SA5.0A/D datasheet and defines the upper voltage limit imposed on protected circuitry during transient events. Designers must verify that this clamping level remains below the absolute maximum ratings of downstream components. The SA12AG consistently achieves this performance across its qualified temperature range (−55°C to +150°C).
Does the SA12AG have UL recognition, and what does it cover?
Yes, the SA12AG carries UL 497B recognition (File #E210057, Category QVGQ2) as part of the fully certified SA5.0A–SA170A series. This certification validates its use in isolated loop circuit protection-not merely flammability compliance-and covers rigorous testing including Strike Voltage Breakdown, Endurance Conditioning, Dielectric Withstand, and Discharge tests. The SA12AG's UL listing directly supports compliance documentation for industrial control panels and medical devices requiring third-party safety validation.
How does the SA12AG differ from bidirectional TVS diodes like the SA12CA?
The SA12AG is unidirectional and functions only during positive transients on its cathode-relative line, making it ideal for DC power rail protection where polarity is fixed. In contrast, the SA12CA is bidirectional and clamps both polarities-suitable for AC signal lines or floating buses. The SA12AG offers lower leakage (<1 µA at 12 V) and tighter VBR tolerance than its bidirectional counterpart, but cannot suppress negative-going surges. Select SA12AG when protecting a defined-polarity 12 V DC path; choose SA12CA only for symmetrical or AC-coupled applications.
What is the thermal resistance and steady-state power rating of the SA12AG?
The SA12AG has a junction-to-lead thermal resistance (RJL) of 33.3°C/W and a steady-state power dissipation (PD) of 3.0 W at TL ≤ 25°C, derating linearly to 30 mW/°C above 50°C. This means sustained power dissipation must remain well below 3 W to avoid thermal runaway-confirming its role as a transient-only protector, not a continuous regulator. The axial Surmetic package enables effective heat transfer via leads into the PCB copper, supporting reliable operation in high-ambient industrial environments where the SA12AG is commonly deployed.
Is the SA12AG RoHS-compliant and compatible with lead-free soldering processes?
Yes, the "G" suffix in SA12AG explicitly denotes a Pb-free Surmetic axial package compliant with RoHS Directive 2011/65/EU. It is qualified for lead-free reflow and wave soldering at peak temperatures up to 260°C for 10 seconds at 1/16″ from the case body. All external surfaces are corrosion-resistant, and leads are readily solderable per J-STD-002. This makes the SA12AG suitable for modern electronics manufacturing without requiring process adjustments-unlike legacy leaded variants that require separate thermal profiling.
SA12AG Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-204AC, DO-15, Axial
- Series:
- MiniMosorb™
- Packaging:
- Bulk
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 12V
- Voltage - Breakdown (Min):
- 13.3V
- Voltage - Clamping (Max) @ Ipp:
- 19.9V
- Current - Peak Pulse (10/1000µs):
- 25.1A
- 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
SA12AG FAQ
1.How can I place an order for SA12AG through Aetrix?
Please submit a Request for Quotation (RFQ) for SA12AG 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 SA12AG reliable?
The price and inventory of SA12AG are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SA12AG is usually 5 days.
3.What payment methods are accepted for SA12AG?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SA12AG transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SA12AG?
SA12AG orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SA12AG 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 SA12AG?
For technical support, including SA12AG datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SA12AG requirements.
6.How does Aetrix verify that SA12AG is sourced from the original manufacturer or authorized distributors?
All SA12AG 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 SA12AG meets industry standards.
7.What is the process for return or replacement of SA12AG?
All SA12AG units undergo pre-shipment inspection (PSI). If there is an issue with SA12AG, 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 SA12AG part is unused and in its original packaging.
Return procedure for SA12AG:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SA12AG Tags
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ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
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D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
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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