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onsemi 1SMA43CAT3
- Part No.:
- 1SMA43CAT3
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
1SMA43CAT3.pdf
- Description:
- TVS DIODE 43VWM 69.4VC SMA
- Quantity:
- Payment:
- Shipping:
Inventory:4,940
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Product details
Overview
1SMA43CAT3 from ON Semiconductor is a bidirectional 400 W peak power Zener transient voltage suppressor (TVS) designed to protect sensitive electronics against ESD and surge events. It features a 43 V working peak reverse voltage (VRWM), 50.2 V clamping voltage at 8.3 A peak pulse current, 2.5 mA max reverse leakage at VRWM, and <1 ns response time. It is used in automotive power supplies and industrial control interfaces requiring robust overvoltage protection.
For engineers reviewing the 1SMA43CAT3 datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage margin relative to system operating voltage, peak pulse current handling under 10/1000 µs waveform, junction capacitance (115 pF at 0 V), thermal resistance (250 °C/W junction-to-ambient), and AEC-Q101 qualification for automotive deployment.
Technical Context
This device operates as a bidirectional Zener-based TVS diode, leveraging avalanche breakdown to clamp transient voltages symmetrically across both polarities. Its low zener impedance and fast sub-nanosecond response enable effective suppression of ESD (Class 3, >16 kV HBM) and lightning-induced surges.
The 1SMA43CAT3 is thermally rated for 0.5 W DC power dissipation at 25°C ambient, with derating to zero at 125°C, and supports soldering at 260°C for 10 seconds. Its SMA package (Case 403D) provides flat handling surface and top/bottom board mounting flexibility.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 43 V - Maximum continuous reverse operating voltage before clamping begins; must exceed circuit's peak DC or AC voltage. |
| VBR min/max | 47.8 V / 52.6 V @ 1 mA - Confirmed breakdown range ensures reliable turn-on within specification tolerance. |
| VC @ IPP | 50.2 V @ 8.3 A - Clamping voltage during 10/1000 µs surge; defines maximum voltage seen by protected IC. |
| PPK | 400 W @ 1 ms - Peak surge power handling capacity under standardized non-repetitive pulse condition. |
| CJ | 115 pF @ 0 V - Junction capacitance impacts high-frequency signal integrity; suitable for DC/low-speed lines, not RF paths. |
| IR @ VRWM | 2.5 µA - Low leakage preserves battery life and avoids false triggering in high-impedance circuits. |
| Response time | <1 ns - Enables protection against fast-rising ESD transients per IEC 61000-4-2. |
Pinout & Package
Package: SMA (Case 403D), surface-mount, Pb-free, void-free molded plastic housing with corrosion-resistant finish and solderable leads. Dimensions: 4.06–4.57 mm length × 2.29–2.92 mm width × 1.97–2.20 mm height.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (marked side) | Transient conduction path (bidirectional) | Marked end indicates cathode; bidirectional operation means either terminal may serve as anode/cathode depending on polarity of transient. |
| Anode (unmarked side) | Transient conduction path (bidirectional) | No dedicated anode/cathode assignment in practice; symmetrical Zener structure enables equal clamping in both directions. |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping | Enables single-device protection of AC-coupled or floating signal lines without polarity concerns. |
| AEC-Q101 qualified | Validated for automotive underhood and powertrain applications requiring extended temperature (-65°C to +150°C) and reliability compliance. |
| ESD Class 3 (>16 kV HBM) | Meets stringent electrostatic discharge immunity required for assembly-line and end-user handling environments. |
| Low-profile SMA package | 0.76–1.52 mm height allows use in space-constrained PCB layouts while maintaining thermal performance via lead-frame conduction. |
Applications
| Automotive Power Supply Protection | Industrial PLC Input Protection |
|---|---|
Use Scenario: Protecting 12 V/24 V battery-fed ECUs from load dump and alternator transients. IC Role / Device Role / Timing Role: Primary overvoltage clamp placed across input rails upstream of DC-DC converters and LDOs. Use Value: Limits transient voltage to ≤50.2 V, preventing damage to downstream regulators rated for 45 V absolute maximum. | Use Scenario: Shielding 24 V digital input modules from field-wiring induced surges in factory automation. IC Role / Device Role / Timing Role: Interface-level TVS mounted directly at connector entry point before optocoupler or Schmitt trigger input. Use Value: Absorbs 400 W surges without degradation, preserving signal integrity and enabling >100,000 surge cycles per IEC 61000-4-5 Level 4. |
| Medical Equipment ESD Guarding | Telecom Line Interface Protection |
Use Scenario: Safeguarding isolated sensor front-ends in portable diagnostic devices exposed to clinical ESD events. IC Role / Device Role / Timing Role: Secondary protection stage after primary gas discharge tube, filtering residual fast transients. Use Value: Sub-1 ns response captures ESD energy missed by slower primary protectors, reducing failure rate in IEC 61000-4-2 testing. | Use Scenario: Protecting RS-485 transceivers in building management systems connected to long outdoor runs. IC Role / Device Role / Timing Role: Bidirectional TVS placed differential-mode across A/B bus lines, referenced to ground. Use Value: Symmetrical clamping maintains common-mode rejection while limiting differential surge voltage to safe levels for ISO 8482-compliant transceivers. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SZ1SMA43CAT3G | Identical electrical specs; includes SZ prefix indicating AEC-Q101 qualification with PPAP capability and controlled manufacturing site. | Required for automotive OEM production where traceability and change control are mandated. | Select SZ1SMA43CAT3G when full automotive qualification documentation and process control are contractually required. |
| 1SMA43AT3G | Unidirectional version; same VRWM, VBR, VC, and PPK, but conducts only in reverse bias - no forward conduction path. | Suitable only for DC-biased lines where polarity is fixed and forward surge risk is absent. | Choose 1SMA43AT3G for cost-sensitive unidirectional applications like 5 V/12 V supply rails with known polarity. |
Compared with 1SMA43CAT3, SZ1SMA43CAT3G adds automotive-grade documentation and process rigor without electrical trade-offs, while 1SMA43AT3G sacrifices bidirectionality for lower unit cost in fixed-polarity designs - selection depends on system-level surge polarity requirements and compliance mandates.
Availability
1SMA43CAT3 is available at Aetrix Electronics and suitable for automotive power supplies, industrial PLC inputs, and medical equipment requiring stable component supply with consistent parametric performance and long-term lifecycle support.
Supply support for 1SMA43CAT3 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 energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, and consumer markets.
The 1SMAxxCAT3G series belongs to ON Semiconductor's SURMETIC® TVS portfolio, engineered specifically for high-reliability transient suppression in harsh environments including automotive underhood, industrial controls, and medical instrumentation.
FAQ
What is the clamping voltage of the 1SMA43CAT3 under standard surge conditions?
The 1SMA43CAT3 has a maximum clamping voltage (VC) of 50.2 V at 8.3 A peak pulse current, measured using the 10/1000 µs waveform defined by R.E.A. This value represents the highest voltage imposed on protected circuitry during a standardized surge event and is critical for ensuring downstream components remain within their absolute maximum ratings.
Is the 1SMA43CAT3 suitable for automotive applications?
Yes, the 1SMA43CAT3 meets AEC-Q101 stress test requirements for transient voltage suppressors and is PPAP-capable. Its operating temperature range of −65°C to +150°C, robust surge handling (400 W), and low leakage (2.5 µA) make it appropriate for engine control units, body electronics, and infotainment power rails where reliability under thermal and electrical stress is mandatory.
How does the bidirectional design of the 1SMA43CAT3 affect its circuit placement?
The bidirectional design of the 1SMA43CAT3 allows placement across any two nodes without regard to polarity - ideal for AC-coupled signals, differential buses like RS-485, or floating grounds. Unlike unidirectional TVS diodes, it requires no orientation check during layout or assembly, simplifying design and reducing manufacturing error risk in the 1SMA43CAT3 implementation.
What is the thermal resistance of the 1SMA43CAT3, and how does it impact PCB layout?
The 1SMA43CAT3 has a junction-to-ambient thermal resistance (RJA) of 250 °C/W under standard FR-4 mounting conditions. To maintain reliability during repeated surges, designers should use minimum recommended copper pads (per Case 403D footprint) and avoid excessive trace isolation - insufficient copper area will cause junction temperature to exceed 150°C, accelerating parameter drift and eventual failure of the 1SMA43CAT3.
Does the 1SMA43CAT3 have Pb-free construction and RoHS compliance?
Yes, the 1SMA43CAT3 is manufactured in a Pb-free, RoHS-compliant SURMETIC® package per ON Semiconductor's environmental policy. The "T3" suffix denotes packaging on a 13-inch tape-and-reel, and the device supports standard lead-free reflow profiles up to 260°C for 10 seconds - fully compatible with modern SMT assembly processes for the 1SMA43CAT3.
1SMA43CAT3 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):
- 43V
- Voltage - Breakdown (Min):
- 47.8V
- Voltage - Clamping (Max) @ Ipp:
- 69.4V
- Current - Peak Pulse (10/1000µs):
- -
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- 150pF @ 1MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMA
1SMA43CAT3 FAQ
1.How can I place an order for 1SMA43CAT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1SMA43CAT3 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 1SMA43CAT3 reliable?
The price and inventory of 1SMA43CAT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1SMA43CAT3 is usually 5 days.
3.What payment methods are accepted for 1SMA43CAT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1SMA43CAT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1SMA43CAT3?
1SMA43CAT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1SMA43CAT3 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 1SMA43CAT3?
For technical support, including 1SMA43CAT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1SMA43CAT3 requirements.
6.How does Aetrix verify that 1SMA43CAT3 is sourced from the original manufacturer or authorized distributors?
All 1SMA43CAT3 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 1SMA43CAT3 meets industry standards.
7.What is the process for return or replacement of 1SMA43CAT3?
All 1SMA43CAT3 units undergo pre-shipment inspection (PSI). If there is an issue with 1SMA43CAT3, 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 1SMA43CAT3 part is unused and in its original packaging.
Return procedure for 1SMA43CAT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1SMA43CAT3 Tags
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onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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Diodes Incorporated
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Diodes Incorporated
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Diodes Incorporated
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Nexperia USA Inc.
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Toshiba Semiconductor and Storage
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Diodes Incorporated
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