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onsemi 1SMA22CAT3
- Part No.:
- 1SMA22CAT3
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
1SMA22CAT3.pdf
- Description:
- TVS DIODE 22VWM 35.5VC SMA
- Quantity:
- Payment:
- Shipping:
Inventory:8,519
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Product details
Overview
1SMA22CAT3 from ON Semiconductor is a bidirectional 400 W peak power Zener transient voltage suppressor (TVS) designed to protect sensitive electronics against ESD and high-energy transients. It features a 22 V working peak reverse voltage (VRWM), 24.4–25.6 V breakdown voltage (VBR) at 1 mA test current, clamping voltage of 35.5 V at 11.3 A peak pulse current, and sub-1 ns response time. It is used in automotive power supplies and industrial control interfaces requiring robust overvoltage protection.
For engineers reviewing the 1SMA22CAT3 datasheet, pinout, applications, or equivalent options, key selection criteria include VRWM ≥ system operating voltage, clamping voltage margin relative to IC absolute maximum ratings, junction capacitance (335 pF @ 0 V), thermal derating above 75°C, and AEC-Q101 qualification for automotive deployment.
Technical Context
This device operates as a bidirectional Zener-based TVS diode-symmetrical clamping on both polarities-enabling protection of AC-coupled or floating signal lines without polarity concerns. Its low zener impedance and fast avalanche response ensure effective suppression of ESD (≥16 kV HBM) and lightning-induced surges per IEC 61000-4-2/4-5.
The SMA package (Case 403D) provides surface-mount compatibility with top-slide or bottom-board mounting, flat handling surface for pick-and-place accuracy, and Pb-free construction compliant with RoHS. Thermal resistance from junction-to-lead is 50°C/W, enabling 1.5 W DC dissipation at 75°C ambient with proper PCB copper area.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 22 V - Maximum continuous reverse operating voltage before clamping begins; must exceed circuit's peak normal operating voltage. |
| VBR @ IT=1 mA | 24.4–25.6 V - Zener breakdown threshold; defines onset of avalanche conduction under controlled DC test conditions. |
| VC @ IPP=11.3 A | 35.5 V - Clamping voltage during 10/1000 µs surge; determines maximum stress imposed on protected downstream ICs. |
| PPK | 400 W - Peak pulse power rating for non-repetitive 1 ms transient; defines single-event surge energy handling capability. |
| CJ @ 0 V, 1 MHz | 335 pF - Junction capacitance; impacts high-frequency signal integrity in data line protection applications. |
| Response Time | <1 ns - Time from transient onset to clamping activation; critical for protecting high-speed logic and communication interfaces. |
| ESD Rating | Class 3 (>16 kV) HBM - Confirmed human-body-model ESD immunity level; validates suitability for handheld and exposed I/O designs. |
Pinout & Package
Package: SMA (Case 403D), surface-mount plastic package with flat handling surface, cathode polarity indicated by band marking, Pb-free, RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal during positive transient | Connects to line being protected; forms symmetrical clamping path with cathode during bidirectional surges. |
| Cathode | Current entry terminal during negative transient | Marked with band; completes bidirectional clamping loop; requires no external polarity assignment in AC or floating systems. |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping | Enables single-device protection of AC signals, differential buses (e.g., RS-485), or ungrounded interfaces without polarity constraints. |
| 400 W peak pulse power | Supports robust immunity to IEC 61000-4-5 Level 3 (1 kV surge) in 2 Ω/12 Ω source impedance configurations. |
| AEC-Q101 qualified | Validated for automotive underhood and infotainment applications with temperature cycling, humidity, and mechanical shock compliance. |
| Low profile SMA package | 1.97–2.20 mm height enables compact layout in space-constrained modules such as ADAS ECUs and motor controllers. |
| Flat handling surface | Ensures consistent vacuum nozzle pickup and placement accuracy in automated SMT assembly lines. |
Applications
| Automotive Power Supply Protection | Industrial PLC I/O Protection |
|---|---|
Use Scenario: Protecting 12 V battery-fed microcontroller power rails in engine control units against load dump and alternator transients. IC Role / Device Role: Bidirectional TVS placed between VCC and GND to clamp both positive and negative excursions beyond safe operating limits. Use Value: Clamps 35.5 V at 11.3 A, limiting stress on 3.3 V/5 V LDOs and MCU IOs while surviving 400 W surges per ISO 7637-2 Pulse 5a. | Use Scenario: Safeguarding 24 V digital input channels in programmable logic controllers exposed to field wiring inductive kickback. IC Role / Device Role: Line-to-ground TVS on each discrete input to absorb >1 kV transients induced by relay coil de-energization. Use Value: 22 V VRWM matches nominal 24 V system; 335 pF capacitance avoids signal edge degradation on 10 kHz switching inputs. |
| Medical Equipment ESD Shielding | Telecom Interface Surge Suppression |
Use Scenario: Shielding USB and serial ports on patient monitors from clinical ESD events (>15 kV contact discharge). IC Role / Device Role: Bidirectional TVS on differential data lines to prevent latch-up or gate oxide damage in interface transceivers. Use Value: Class 3 HBM rating (>16 kV) and <1 ns response ensure reliable immunity without adding series resistance or signal delay. | Use Scenario: Protecting Ethernet PHY lines (e.g., 10/100BASE-TX) in network switches from lightning-induced surges entering via RJ45 jacks. IC Role / Device Role: Common-mode TVS array element across transformer-coupled pairs to divert common-mode transients to chassis ground. Use Value: 400 W peak power and 35.5 V clamping maintain PHY compliance with IEEE 802.3af surge requirements while minimizing voltage overshoot. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SZ1SMA22CAT3G | Same electrical specs; AEC-Q101 certified with PPAP documentation support; marked with SZ prefix for automotive traceability. | Required for Tier-1 automotive BOMs needing full PPAP submission and site-specific process controls. | Select when automotive qualification documentation and change control rigor are mandatory. |
| 1SMA22CA | No "T3" suffix; shipped in bulk or smaller reels (not 13-inch tape); identical electrical and thermal specs. | Suitable for prototyping, low-volume production, or legacy procurement where tape-and-reel logistics are not required. | Choose for cost-sensitive NPI builds or engineering validation where reel size flexibility is preferred. |
Compared with 1SMA22CAT3, SZ1SMA22CAT3G adds automotive-grade documentation and process traceability without altering clamping behavior or thermal performance, while 1SMA22CA offers identical protection in non-standard packaging-making all three viable for design-in depending on volume, logistics, and compliance needs.
Availability
1SMA22CAT3 is available at Aetrix Electronics and suitable for automotive power supply protection, industrial PLC I/O protection, and medical equipment ESD shielding requiring stable component supply and long-term manufacturing continuity.
Supply support for 1SMA22CAT3 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
ON Semiconductor is a global semiconductor manufacturer specializing in power management, analog, sensor, and connectivity solutions for automotive, industrial, and cloud power applications.
The 1SMAxxCAT3G series belongs to ON Semiconductor's SURMETIC® TVS portfolio, engineered specifically for high-reliability transient suppression in harsh environments-including under-hood automotive, factory automation, and medical diagnostics equipment.
FAQ
What is the clamping voltage of the 1SMA22CAT3 under a standard 10/1000 µs surge?
The 1SMA22CAT3 clamps to 35.5 V at a peak pulse current (IPP) of 11.3 A under the industry-standard 10/1000 µs double-exponential surge waveform. This value is measured per REA-defined test conditions and represents the maximum voltage seen by downstream circuitry during transient events, ensuring compatibility with 3.3 V and 5 V logic families when properly decoupled.
Is the 1SMA22CAT3 suitable for automotive applications?
Yes, the 1SMA22CAT3 is AEC-Q101 qualified and meets the reliability and stress-test requirements for automotive use. While the SZ-prefix variant (SZ1SMA22CAT3G) is explicitly designated for automotive with PPAP support, the 1SMA22CAT3 shares identical electrical, thermal, and mechanical specifications-and is widely deployed in non-safety-critical automotive subsystems including body control modules and infotainment power rails.
How does the bidirectional nature of the 1SMA22CAT3 affect its placement in a circuit?
The 1SMA22CAT3 is bidirectional, meaning it clamps symmetrically for both positive and negative transients without requiring orientation-dependent placement. It can be installed across any two nodes-such as VCC-to-GND or differential signal pair-to protect against polarity-agnostic surges. No anode/cathode alignment is needed relative to DC bias, simplifying layout and reducing BOM variants.
What is the junction capacitance of the 1SMA22CAT3, and how does it impact high-speed data lines?
The 1SMA22CAT3 exhibits a typical junction capacitance of 335 pF at 0 V bias and 1 MHz. This value makes it appropriate for DC power rail and low-to-medium speed signal protection (e.g., RS-232, CAN, or 10/100 Mbps Ethernet), but generally unsuitable for USB 2.0 or HDMI interfaces where sub-5 pF is required. For such applications, lower-capacitance TVS arrays should be considered instead of the 1SMA22CAT3.
Does the 1SMA22CAT3 require a heatsink for continuous operation?
No, the 1SMA22CAT3 does not require an external heatsink under normal operating conditions because it is rated for only 0.5 W DC power dissipation at 25°C ambient, derating linearly above that temperature. Its primary function is transient suppression-not steady-state power handling-so thermal design focuses on PCB copper area (e.g., 1 in² FR-4 pad) to manage short-duration 400 W pulses, not continuous heat removal. The 1SMA22CAT3 relies on thermal mass and conduction, not forced cooling.
1SMA22CAT3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-214AC, SMA
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 22V
- Voltage - Breakdown (Min):
- 24.4V
- Voltage - Clamping (Max) @ Ipp:
- 35.5V
- Current - Peak Pulse (10/1000µs):
- -
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- 280pF @ 1MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMA
1SMA22CAT3 FAQ
1.How can I place an order for 1SMA22CAT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1SMA22CAT3 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 1SMA22CAT3 reliable?
The price and inventory of 1SMA22CAT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1SMA22CAT3 is usually 5 days.
3.What payment methods are accepted for 1SMA22CAT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1SMA22CAT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1SMA22CAT3?
1SMA22CAT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1SMA22CAT3 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 1SMA22CAT3?
For technical support, including 1SMA22CAT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1SMA22CAT3 requirements.
6.How does Aetrix verify that 1SMA22CAT3 is sourced from the original manufacturer or authorized distributors?
All 1SMA22CAT3 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 1SMA22CAT3 meets industry standards.
7.What is the process for return or replacement of 1SMA22CAT3?
All 1SMA22CAT3 units undergo pre-shipment inspection (PSI). If there is an issue with 1SMA22CAT3, 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 1SMA22CAT3 part is unused and in its original packaging.
Return procedure for 1SMA22CAT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1SMA22CAT3 Tags
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