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STMicroelectronics SM30T56CAY
- Part No.:
- SM30T56CAY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SM30T56CAY.pdf
- Description:
- TVS DIODE 48VWM 76.6VC SMC
- Quantity:
- Payment:
- Shipping:
Inventory:3,615
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Product details
Overview
SM30T56CAY from STMicroelectronics is a bidirectional automotive-grade transient voltage suppression (TVS) diode in SMC package, designed for ISO 7637-2 pulse protection and ISO 10605 ESD immunity in 12 V/24 V vehicle systems. It delivers 3000 W peak pulse power (10/1000 µs), clamps at 76.6 V (max) under 38.0 A surge, and operates up to 175 °C junction temperature - enabling robust protection of CAN, LIN, and sensor interfaces in engine control units and body electronics.
For engineers reviewing the SM30T56CAY datasheet, SM30T56CAY pinout, SM30T56CAY application, or SM30T56CAY equivalent, key selection criteria include its bidirectional configuration, 56 V breakdown voltage (VBR = 53.2–58.8 V), low leakage (0.2 µA at 25 °C), JEDEC-compliant SMC footprint, and AEC-Q101 qualification for under-hood deployment.
Technical Context
This TVS diode uses planar silicon technology to achieve stable high-temperature operation (Tj up to +175 °C) and ultra-low leakage current (0.2 µA at 25 °C), critical for long-term reliability in automotive power domains. Its bidirectional architecture provides symmetrical clamping for both positive and negative transients without polarity dependency.
The device meets stringent automotive surge standards: ISO 7637-2 Pulse 1 (−150 V), Pulse 2a (+112 V), Pulse 3a (−220 V), Pulse 3b (+150 V), and exceeds IEC 61000-4-2 Level 4 ESD with ±30 kV air/contact discharge (C = 150 pF / R = 330 Ω and C = 330 pF / R = 330 Ω).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR (min/typ/max) | 53.2 / 56.0 / 58.8 V - ensures reliable triggering above system nominal voltage while avoiding false trips during load dump overshoot. |
| VCL (max) @ IPP | 76.6 V @ 38.0 A (10/1000 µs) - defines maximum voltage seen by protected IC during worst-case surge, safeguarding 75 V-rated components. |
| PPP | 3000 W (10/1000 µs) - sustains high-energy transients common in alternator load dump and inductive switching events. |
| IR (max) | 0.2 µA at VRM = 48 V, 25 °C - minimizes standby power loss and prevents signal distortion in high-impedance sensor lines. |
| Tj (max) | +175 °C - supports placement near heat sources (e.g., power modules, ECUs) without derating or thermal shutdown. |
| Standards | AEC-Q101 qualified; ISO 7637-2, ISO 10605, IEC 61000-4-2, IEC 61000-4-4 Level 4 - certified for full automotive electrical environment compliance. |
Pinout & Package
SM30T56CAY is housed in a JEDEC-standard SMC (DO-214AB) surface-mount package with matte tin-plated leads and IPC-7531-compliant footprint. The bidirectional configuration has no anode/cathode polarity - both terminals are functionally identical for transient clamping.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (A) | Transient clamp terminal | One side of symmetrical PN junction; connects to protected line (e.g., CAN_H or LIN bus) without polarity constraint. |
| Cathode (K) | Transient clamp terminal | Other side of symmetrical PN junction; ties to same reference as Anode - forms bidirectional clamping path across protected node. |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping | Enables single-device protection of AC-coupled or floating buses (e.g., CAN, FlexRay) without external polarity management. |
| Low dynamic resistance (RD) | 101 mΩ - reduces clamping voltage rise under high di/dt surges, improving margin for downstream 5 V/3.3 V logic. |
| AEC-Q101 qualification | Validated for automotive temperature cycling, humidity bias, and mechanical shock - required for Tier-1 ECU BOM inclusion. |
| High-temperature leakage stability | IR remains ≤1 µA up to 125 °C (per Figure 9) - avoids false resets or analog offset drift in hot under-hood environments. |
| JEDEC SMC outline compliance | Ensures drop-in compatibility with existing PCB footprints and automated assembly processes across global manufacturing sites. |
Applications
| Engine Control Unit (ECU) Power Input | CAN FD Transceiver Protection |
|---|---|
|
Use Scenario: Protects 12 V supply rail of diesel/gasoline engine ECUs against ISO 7637-2 Pulse 5b load dump (up to 87 V, 400 ms) and battery reversal spikes. IC Role / Device Role: Primary overvoltage clamp placed upstream of DC-DC converters and microcontroller power rails. Use Value: Limits input voltage to ≤76.6 V during 38 A surge, preventing damage to 75 V-rated input capacitors and LDO regulators. |
Use Scenario: Shields high-speed CAN FD physical layer transceivers (e.g., TJA1057) from ESD events and coupled noise on vehicle harnesses. IC Role / Device Role: Bidirectional line protector on CAN_H/CAN_L differential pair, mounted adjacent to connector. Use Value: Clamps ±30 kV ESD strikes to <77 V within nanoseconds, preserving signal integrity and preventing transceiver latch-up. |
| Body Control Module (BCM) Sensor Interface | ADAS Camera Power Line |
|
Use Scenario: Guards analog inputs (e.g., temperature, pressure sensors) in BCMs exposed to ISO 7637-2 Pulse 3a (−220 V) and Pulse 3b (+150 V) transients. IC Role / Device Role: Low-leakage TVS on sensor signal lines referenced to chassis ground. Use Value: Maintains <0.2 µA leakage at 25 °C and <1 µA at 125 °C, eliminating measurement error in µA-range current-sense circuits. |
Use Scenario: Secures 12 V power feed to 5 MP automotive cameras in ADAS domain controllers subjected to vibration-induced arcing and alternator ripple. IC Role / Device Role: Secondary surge suppressor downstream of primary front-end protection, placed near camera module connector. Use Value: Withstands repeated 3000 W surges while operating continuously at 175 °C junction temperature - essential for sealed, convection-limited camera housings. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ58CA (onsemi) | Lower PPP (400 W), higher VCL (93.6 V @ 4.3 A), SMC package, AEC-Q101 not claimed | Limited to lower-energy surges; insufficient for ISO 7637-2 Pulse 1/3a in 24 V systems | Select only for cost-sensitive non-AEC-Q101 interior modules with <500 W surge exposure. |
| TPSMB58CA (Texas Instruments) | Same PPP (3000 W), identical VBR/VCL, but rated only to Tj = 150 °C and lacks ISO 7637-2 Pulse 5b validation | Not qualified for under-hood use above 150 °C; requires additional thermal margin in ECU designs | Acceptable for cabin-mounted modules (e.g., infotainment) where ambient Ta < 85 °C and load dump is filtered externally. |
Compared with SMAJ58CA and TPSMB58CA, SM30T56CAY uniquely combines AEC-Q101 qualification, 175 °C operation, and full ISO 7637-2 Pulse 5b validation - making it the only choice for unfiltered 12 V/24 V power rail protection in engine compartments and ADAS edge nodes.
Availability
SM30T56CAY is available at Aetrix Electronics and suitable for automotive engine control units, CAN FD networks, body control modules, and ADAS camera power systems requiring stable component supply across extended temperature and surge stress conditions.
Supply support for SM30T56CAY 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, delivering automotive, industrial, and power management solutions with vertical manufacturing and application-focused design centers.
SM30T56CAY belongs to the SM30TY series of planar TVS diodes engineered specifically for AEC-Q101-compliant automotive surge protection - targeting high-reliability, high-temperature, and low-leakage requirements in next-generation vehicle electronics.
FAQ
Is SM30T56CAY unidirectional or bidirectional?
SM30T56CAY is a bidirectional TVS diode, indicated by the "CAY" suffix per ST's marking table (3BASY). Its symmetrical V-I characteristic clamps both positive and negative transients equally, making it ideal for differential buses like CAN and LIN where polarity is undefined during fault conditions.
What is the maximum clamping voltage at 38 A surge current?
The maximum clamping voltage (VCL) for SM30T56CAY is 76.6 V when subjected to a 10/1000 µs waveform at 38.0 A peak current, as specified in Table 2 of DS8599 Rev 13. This value is measured at Tamb = 25 °C and defines the upper voltage limit imposed on protected circuitry during worst-case surge events.
Does SM30T56CAY meet ISO 7637-2 Pulse 5b (load dump) requirements?
Yes - SM30T56CAY is validated for ISO 7637-2 Pulse 5b (load dump) per Figures 18–22 in DS8599. It withstands Us = 87 V with tp = 150 ms and 400 ms waveforms using Schaffner LD 5505 generator testing, confirming suitability for direct connection to automotive battery rails without upstream filtering.
Can SM30T56CAY replace SM30T56AY in a bidirectional design?
No - SM30T56AY is unidirectional (A-suffix), while SM30T56CAY is bidirectional (C-suffix). Substituting them requires verifying circuit polarity: unidirectional types require correct anode/cathode orientation and cannot clamp reverse-polarity transients. Using SM30T56AY in place of SM30T56CAY risks failure during negative surges like ISO 7637-2 Pulse 1 or 3a.
SM30T56CAY Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AB, SMC
- Series:
- SM30TY, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 48V
- Voltage - Breakdown (Min):
- 53.2V
- Voltage - Clamping (Max) @ Ipp:
- 76.6V
- Current - Peak Pulse (10/1000µs):
- 38A
- Power - Peak Pulse:
- 3000W (3kW)
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMC
SM30T56CAY FAQ
1.How can I place an order for SM30T56CAY through Aetrix?
Please submit a Request for Quotation (RFQ) for SM30T56CAY 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 SM30T56CAY reliable?
The price and inventory of SM30T56CAY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM30T56CAY is usually 5 days.
3.What payment methods are accepted for SM30T56CAY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM30T56CAY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM30T56CAY?
SM30T56CAY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM30T56CAY 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 SM30T56CAY?
For technical support, including SM30T56CAY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM30T56CAY requirements.
6.How does Aetrix verify that SM30T56CAY is sourced from the original manufacturer or authorized distributors?
All SM30T56CAY 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 SM30T56CAY meets industry standards.
7.What is the process for return or replacement of SM30T56CAY?
All SM30T56CAY units undergo pre-shipment inspection (PSI). If there is an issue with SM30T56CAY, 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 SM30T56CAY part is unused and in its original packaging.
Return procedure for SM30T56CAY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SM30T56CAY Tags
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