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STMicroelectronics SM30T7.5CAY
- Part No.:
- SM30T7.5CAY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SM30T7.5CAY.pdf
- Description:
- TVS DIODE 6.5VWM 11.2VC SMC
- Quantity:
- Payment:
- Shipping:
Inventory:2,241
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Product details
Overview
SM30T7.5CAY 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 vehicle systems. It features a 7.5 V nominal breakdown voltage (VBR), 11.2 V clamping voltage (VCL) at 268 A (10/1000 µs), 3000 W peak pulse power, 0.2 µA leakage current at 25 °C, and operates up to 175 °C junction temperature.
For engineers reviewing the SM30T7.5CAY datasheet, SM30T7.5CAY pinout, SM30T7.5CAY application, or SM30T7.5CAY equivalent, this device is selected for robust front-end surge protection in automotive body control modules, infotainment power rails, and LIN/CAN transceiver interfaces where low-leakage, high-temperature stability, and bidirectional clamping are required.
Technical Context
This bidirectional TVS uses planar silicon technology to achieve stable VBR temperature coefficient (αT = 4.77 × 10−4/°C) and low dynamic resistance (RD = 6.1 mΩ), enabling precise clamping under fast transients like ISO 7637-2 Pulse 3a (−220 V) and Pulse 3b (+150 V). Its symmetrical I-V characteristics support protection of AC-coupled or differential signal lines without polarity constraints.
It meets AEC-Q101 qualification and exceeds IEC 61000-4-2 Level 4 (±30 kV air/contact discharge) and ISO 10605 (C = 150 pF/R = 330 Ω and C = 330 pF/R = 330 Ω), with validated performance across −55 °C to +175 °C operating junction range and JEDEC-compliant SMC footprint.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR (min/typ/max) | 7.2 V / 7.5 V / 7.9 V - ensures reliable turn-on before downstream IC damage at 12 V system rail |
| VCL @ 268 A (10/1000 µs) | 11.2 V - limits transient overvoltage to safe level for 5 V or 3.3 V logic interfaces |
| IPP (10/1000 µs) | 268 A - supports full ISO 7637-2 Pulse 1 (−150 V) energy absorption on 500 mΩ source impedance |
| Leakage current IR | 0.2 µA at VRM = 6.5 V - prevents battery drain in always-on automotive circuits |
| Junction temperature Tj | −55 °C to +175 °C - enables placement near hot engine-control units without derating |
| Dynamic resistance RD | 6.1 mΩ - minimizes VCL rise under high-current surges, improving clamping precision |
| ESD rating (IEC 61000-4-2) | ±30 kV contact/air - exceeds automotive infotainment and sensor interface immunity requirements |
Pinout & Package
The SM30T7.5CAY is housed in a JEDEC-registered SMC (DO-214AB) surface-mount package with matte tin-plated leads, compatible with IPC-7531 footprint and reflow soldering per J-STD-020 MSL Level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Cathode for unidirectional) | Transient current entry point (bidirectional symmetry) | Both terminals behave identically - no polarity dependency; connects to protected line and ground reference |
| Cathode (Anode for unidirectional) | Transient current return path (bidirectional symmetry) | Identical to Anode terminal; enables protection of differential buses (e.g., LIN, CAN FD stubs) without orientation concerns |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping | Enables single-device protection of AC-coupled or floating signal paths (e.g., LIN bus, sensor bridges) without external polarity management |
| AEC-Q101 qualified | Validated for automotive under-hood and cabin environments including thermal cycling, humidity, and mechanical shock per JESD47 |
| Low 0.2 µA leakage | Permits direct placement on always-powered domains (e.g., wake-up circuits, real-time clocks) without compromising standby current budget |
| 175 °C max Tj | Supports mounting adjacent to power converters or ECUs with minimal thermal derating, extending board-level reliability |
| 3000 W (10/1000 µs) PPP | Handles full ISO 7637-2 Pulse 1 (−150 V) and Pulse 2a (+112 V) without degradation across 1000+ surge events |
Applications
| Body Control Module (BCM) | Infotainment Power Rail |
|---|---|
Use Scenario: Protects 12 V input to microcontroller-based BCM during load dump and alternator ripple events. IC Role / Device Role / Timing Role: Bidirectional TVS placed between battery feed and DC-DC converter input to clamp transients before regulation. Use Value: Prevents latch-up or burnout of buck controller ICs by limiting VIN to ≤11.2 V during 268 A surges, maintaining system uptime. | Use Scenario: Shields USB-C PD and HDMI power domains in head unit against ESD and conducted noise from HVAC motors. IC Role / Device Role / Timing Role: Front-end surge suppressor on 5 V/12 V auxiliary rails feeding PMICs and audio codecs. Use Value: Eliminates need for secondary filtering stages due to sub-µA leakage and <12 V clamping, reducing BOM count and PCB area. |
| LIN Transceiver Interface | Engine Coolant Sensor Circuit |
Use Scenario: Guards LIN bus pins against ESD during service port connection and electromagnetic coupling from nearby solenoids. IC Role / Device Role / Timing Role: Low-capacitance bidirectional TVS directly at transceiver PHY pins to preserve signal integrity. Use Value: Maintains LIN timing margins (≤20 ns edge distortion) while delivering ±30 kV ESD immunity-no added propagation delay. | Use Scenario: Protects analog output of NTC-based coolant sensor exposed to harness-induced spikes during starter engagement. IC Role / Device Role / Timing Role: Signal-line TVS between sensor element and ADC input of engine control unit. Use Value: Ensures <0.1% measurement error by limiting transient-induced offset shift via 6.1 mΩ RD and stable VBR over −40 °C to +150 °C. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ7.5CA | Lower PPP (400 W), higher VCL (12.9 V), same SMC package | Not rated for AEC-Q101; limited to non-automotive industrial use | Select only for cost-sensitive non-automotive designs where 3000 W surge margin is unnecessary |
| TPSMD7.5C | Same 3000 W PPP but higher leakage (1 µA), different thermal resistance (Rth(j-a) = 45 °C/W vs. 35 °C/W) | Qualified to AEC-Q101 but lacks ISO 7637-2 Pulse 5b validation | Prefer when ESD-only protection suffices and thermal dissipation is less constrained |
Compared with SMAJ7.5CA and TPSMD7.5C, SM30T7.5CAY delivers superior automotive readiness through AEC-Q101 validation, lower leakage, tighter VCL, and documented ISO 7637-2 Pulse 1–3b performance-making it the only choice for safety-critical 12 V domain protection.
Availability
SM30T7.5CAY is available at Aetrix Electronics and suitable for automotive body electronics, infotainment power conditioning, and LIN/CAN physical layer protection requiring stable component supply across extended temperature and long product lifecycles.
Supply support for SM30T7.5CAY 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, specializing in automotive, industrial, and power management solutions with vertical manufacturing and broad IP portfolio.
The SM30Txx series belongs to ST's automotive-grade TVS portfolio, engineered specifically for ISO 7637-2 and ISO 10605 compliance in 12 V and 24 V vehicle architectures-prioritizing low leakage, high-temperature operation, and bidirectional symmetry for modern E/E architecture resilience.
FAQ
What is the maximum clamping voltage for SM30T7.5CAY under a 10/1000 µs surge?
The maximum clamping voltage (VCL) is 11.2 V at 268 A for a 10/1000 µs waveform, measured at Tamb = 25 °C. This value increases linearly with junction temperature using αT = 4.77 × 10−4/°C, reaching ~12.1 V at Tj = 150 °C per the datasheet's VCL vs. Tj formula.
Is SM30T7.5CAY suitable for protecting CAN FD data lines?
No-SM30T7.5CAY is not optimized for high-speed data lines due to its junction capacitance (~300 nF at 1 V reverse bias), which would severely distort >2 Mbps CAN FD signals. It is intended for power rail and low-frequency signal protection (e.g., LIN, sensor analog outputs), not data bus clamping.
How does SM30T7.5CAY differ from the unidirectional SM30T7.5AY?
SM30T7.5CAY is bidirectional with symmetrical breakdown in both polarities (VBR = 7.5 V ±0.3 V either way), while SM30T7.5AY is unidirectional with forward conduction below 1.5 V and reverse breakdown at 7.5 V. The CAY version protects AC-coupled or floating nodes; AY suits DC-biased rails where polarity is fixed.
Does SM30T7.5CAY require derating above 85 °C ambient?
Yes-peak pulse power must be derated linearly from 3000 W at Tj = 25 °C to ~1800 W at Tj = 125 °C per Figure 3 in DS8599 Rev 13. Derating is based on junction temperature, not ambient; proper copper pour design (≥3 cm² per lead) is required to maintain Tj ≤ 175 °C under repeated surges.
SM30T7.5CAY 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):
- 6.5V
- Voltage - Breakdown (Min):
- 7.13V
- Voltage - Clamping (Max) @ Ipp:
- 11.2V
- Current - Peak Pulse (10/1000µs):
- 268A
- 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
SM30T7.5CAY FAQ
1.How can I place an order for SM30T7.5CAY through Aetrix?
Please submit a Request for Quotation (RFQ) for SM30T7.5CAY 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 SM30T7.5CAY reliable?
The price and inventory of SM30T7.5CAY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM30T7.5CAY is usually 5 days.
3.What payment methods are accepted for SM30T7.5CAY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM30T7.5CAY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM30T7.5CAY?
SM30T7.5CAY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM30T7.5CAY 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 SM30T7.5CAY?
For technical support, including SM30T7.5CAY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM30T7.5CAY requirements.
6.How does Aetrix verify that SM30T7.5CAY is sourced from the original manufacturer or authorized distributors?
All SM30T7.5CAY 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 SM30T7.5CAY meets industry standards.
7.What is the process for return or replacement of SM30T7.5CAY?
All SM30T7.5CAY units undergo pre-shipment inspection (PSI). If there is an issue with SM30T7.5CAY, 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 SM30T7.5CAY part is unused and in its original packaging.
Return procedure for SM30T7.5CAY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SM30T7.5CAY Tags
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