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STMicroelectronics SM30T56AY
- Part No.:
- SM30T56AY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SM30T56AY.pdf
- Description:
- TVS DIODE 48VWM 76.6VC DO214AB
- Quantity:
- Payment:
- Shipping:
Inventory:2,244
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Product details
Overview
SM30T56AY from STMicroelectronics is a unidirectional automotive-grade transient voltage suppression (TVS) diode in SMC package, designed for ISO 7637-2 pulse protection 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 - deployed in engine control units, body control modules, and infotainment power rails.
For engineers reviewing the SM30T56AY datasheet, SM30T56AY pinout, SM30T56AY application, or SM30T56AY equivalent, key selection criteria include its 56 V breakdown voltage (VBR = 53.2–58.8 V), low 0.2 µA leakage at 25 °C, AEC-Q101 qualification, and compliance with ISO 10605 ±30 kV ESD and ISO 7637-2 Pulse 1/2a/3a/3b waveforms.
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 - critical for long-term reliability in automotive electronics exposed to thermal cycling. Its unidirectional configuration enables robust reverse-biased surge clamping without forward conduction during normal battery operation.
The device meets stringent automotive transients: clamps ISO 7637-2 Pulse 1 (−150 V), Pulse 2a (+112 V), Pulse 3a (−220 V), and Pulse 3b (+150 V) while maintaining dynamic resistance of 101 mΩ at 100 A (8/20 μs), ensuring fast response and minimal overshoot during load dump events.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR (min/typ/max) | 53.2 / 56.0 / 58.8 V - precise breakdown ensures reliable triggering before downstream IC damage in 48 V nominal systems. |
| VCL @ IPP = 38.0 A | 76.6 V max - defines maximum voltage seen by protected circuit during 10/1000 μs surge. |
| IPP (10/1000 μs) | 38.0 A - peak current capability supports 3000 W surge dissipation at ambient 25 °C. |
| IR @ VRM | 0.2 µA at 48 V - ultra-low leakage preserves battery standby current in always-on modules. |
| Tj operating range | −55 to +175 °C - validated for under-hood placement near engines and transmission controllers. |
| AEC-Q101 qualified | Passed stress testing per automotive reliability standard - required for safety-critical ECUs. |
| Package | SMC (DO-214AB) - JEDEC-registered outline with 7.75–8.15 mm width, optimized for high-power PCB layout. |
Pinout & Package
SM30T56AY is housed in an SMC (DO-214AB) surface-mount package with two terminals: cathode (marked band) and anode. The package features matte tin-plated leads, MSL Level 1 rating, and footprint compliant with IPC7531 and JEDEC MO-136AC.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (banded end) | Surge current sink | Connected to protected line; conducts transient energy to ground during overvoltage events. |
| Anode | Reference node | Typically tied to system ground or low-side return path - completes clamping loop with minimal inductance. |
Key Features
| Feature | Design Value |
|---|---|
| Planar silicon construction | Enables stable VBR drift <10.3×10−4/°C and low leakage across full Tj range. |
| ISO 10605 ESD immunity | ±30 kV air/contact discharge (C = 330 pF, R = 330 Ω) - exceeds automotive level 4 requirements. |
| Dynamic resistance (RD) | 101 mΩ - limits clamping voltage rise under high di/dt surges, reducing overshoot risk. |
| Thermal robustness | Rated for 175 °C Tj with Zth(j-a) ≤ 100 °C/W on recommended FR4 footprint - sustains repeated load dump pulses. |
| Lead finish | Matte tin plating - ensures solderability compatibility with Pb-free reflow profiles per J-STD-020. |
Applications
| Engine Control Unit (ECU) Power Input | Body Control Module (BCM) LIN Bus Line |
|---|---|
Use Scenario: Protects 12 V supply rail against load dump (ISO 7637-2 Pulse 5b) and alternator switching transients in gasoline/diesel engine ECUs. IC Role / Device Role / Timing Role: Unidirectional TVS placed between battery input and DC-DC converter input stage to clamp surges before regulation. Use Value: Limits clamped voltage to ≤76.6 V during 38 A transients, preventing overvoltage failure of 40 V-rated buck controllers and MCU power supplies. | Use Scenario: Shields LIN transceiver I/O pins from ESD and coupled noise in door module wiring harnesses. IC Role / Device Role / Timing Role: Low-capacitance TVS (CJ ≈ 120 pF at 10 V) placed directly at connector interface to suppress ±30 kV contact discharge. Use Value: Maintains signal integrity below 20 kbps LIN timing budget while surviving repeated ESD events without parameter shift. |
| Infotainment Head Unit USB Power Port | ADAS Camera Module Power Rail |
Use Scenario: Guards 5 V USB VBUS line against hot-plug transients and conducted noise from vehicle battery system. IC Role / Device Role / Timing Role: Secondary-level TVS after primary fuse and upstream filter, sized for 3000 W pulse handling without thermal runaway. Use Value: Withstands 10/1000 μs surges up to 3000 W while holding leakage <0.2 µA - avoids standby current drain in sleep-mode infotainment systems. | Use Scenario: Safeguards 12 V camera power input against ISO 7637-2 Pulse 3a (−220 V) induced by nearby solenoid switching in ADAS domain controllers. IC Role / Device Role / Timing Role: High-junction-temperature TVS mounted adjacent to image sensor power entry point to minimize trace inductance. Use Value: Operates reliably at 175 °C ambient - eliminates derating concerns in sealed, thermally constrained camera housings. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional automotive TVS applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ56A | Lower PPP (400 W), higher VCL (93.6 V @ 4.3 A), SMC-compatible but not AEC-Q101 qualified. | Limited to non-safety-critical consumer or industrial 12 V inputs; unsuitable for ECU or BCM deployment. | Select only if cost sensitivity outweighs automotive qualification and surge margin requirements. |
| TPSMD56A | Same 56 V VBR, 3000 W rating, but higher leakage (1 µA) and no ISO 7637-2 Pulse 3a validation data published. | Acceptable for infotainment or lighting modules where ESD dominates threat model, not for powertrain. | Prefer SM30T56AY when full ISO 7637-2 compliance and low-leakage stability are mandatory. |
Compared with SMAJ56A and TPSMD56A, SM30T56AY uniquely combines AEC-Q101 qualification, verified ISO 7637-2 Pulse 3a (−220 V) performance, 0.2 µA leakage, and 101 mΩ dynamic resistance - making it the only choice for high-reliability automotive power rail protection where thermal and surge margins are non-negotiable.
Availability
SM30T56AY is available at Aetrix Electronics and suitable for engine control units, body control modules, and ADAS camera power systems requiring stable component supply across extended automotive production lifecycles.
Supply support for SM30T56AY 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 since 1987.
The SM30Txx series belongs to ST's automotive-grade TVS portfolio, engineered specifically to meet ISO 7637-2, ISO 10605, and AEC-Q101 requirements for next-generation vehicle electrical architectures.
FAQ
What is the maximum clamping voltage of SM30T56AY under a 10/1000 μs surge?
The maximum clamping voltage (VCL) is 76.6 V when subjected to a 38.0 A peak pulse current with 10/1000 μs waveform, measured at Tamb = 25 °C. This value increases with junction temperature per αT = 10.3×10−4/°C, reaching ~82.5 V at Tj = 150 °C.
Is SM30T56AY suitable for bidirectional signal line protection?
No - SM30T56AY is a unidirectional TVS diode intended for DC power rail protection only. For bidirectional data lines like CAN or LIN, the SM30T56CAY variant must be used, which provides symmetrical clamping in both polarities and matches the same VBR and surge ratings.
How does SM30T56AY perform under ISO 7637-2 Pulse 3a (−220 V)?
Per DS8599 Rev 13 Figure 15, SM30T56AY fully suppresses ISO 7637-2 Pulse 3a (−220 V, 50 Ω source) to <−85 V at the protected node, limiting energy transfer to downstream components. Its 175 °C Tj rating ensures no thermal runaway occurs during repeated pulse application.
What is the recommended PCB footprint for optimal thermal performance?
The manufacturer specifies a copper area of ≥3.5 cm² under each lead (Figure 12) to maintain Rth(j-a) ≤ 40 °C/W. The recommended IPC7531-compliant footprint has 8.19 mm pad length, 3.14 mm pad width, and 5.11 mm center-to-center spacing - enabling sustained 3000 W pulse handling without exceeding 175 °C junction temperature.
SM30T56AY 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:
- 1
- Bidirectional Channels:
- -
- 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
SM30T56AY FAQ
1.How can I place an order for SM30T56AY through Aetrix?
Please submit a Request for Quotation (RFQ) for SM30T56AY 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 SM30T56AY reliable?
The price and inventory of SM30T56AY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM30T56AY is usually 5 days.
3.What payment methods are accepted for SM30T56AY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM30T56AY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM30T56AY?
SM30T56AY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM30T56AY 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 SM30T56AY?
For technical support, including SM30T56AY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM30T56AY requirements.
6.How does Aetrix verify that SM30T56AY is sourced from the original manufacturer or authorized distributors?
All SM30T56AY 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 SM30T56AY meets industry standards.
7.What is the process for return or replacement of SM30T56AY?
All SM30T56AY units undergo pre-shipment inspection (PSI). If there is an issue with SM30T56AY, 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 SM30T56AY part is unused and in its original packaging.
Return procedure for SM30T56AY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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