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STMicroelectronics SM30T30CAY
- Part No.:
- SM30T30CAY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SM30T30CAY.pdf
- Description:
- TVS DIODE 26VWM 42.1VC SMC
- Quantity:
- Payment:
- Shipping:
Inventory:583
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Product details
Overview
SM30T30CAY 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 42.1 V (max) under 71 A surge, and operates up to 175 °C junction temperature with only 0.2 µA leakage at 25 °C.
For engineers reviewing the SM30T30CAY datasheet, SM30T30CAY pinout, SM30T30CAY application, or SM30T30CAY equivalent, this device is selected for robust front-end protection of CAN/LIN transceivers, body control modules, and infotainment power rails where low capacitance (<100 pF), high Tj stability, and AEC-Q101 qualification are mandatory.
Technical Context
The SM30T30CAY employs planar silicon avalanche technology to achieve precise breakdown symmetry (VBR = 28.9–31.9 V) and low dynamic resistance (RD = 34.5 mΩ) across bidirectional conduction paths. Its thermal design supports sustained operation at 175 °C junction temperature, validated per JESD22-A103 and J-STD-020 MSL Level 1.
It 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 (±30 kV contact/air discharge) and ISO 10605 (C = 330 pF, R = 330 Ω).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power (10/1000 µs) | 3000 W - sustains 71 A surge current without failure in standard automotive load dump events |
| Clamping Voltage (IPP = 71 A) | 42.1 V max - limits downstream IC voltage stress during ISO 7637-2 Pulse 3b (+150 V) |
| Breakdown Voltage (VBR) | 28.9–31.9 V at 1 mA - ensures reliable triggering before damage to 33 V-rated components |
| Leakage Current (IRM) | 0.2 µA at VRM = 30 V - minimizes standby power loss in always-on vehicle networks |
| Junction Temperature Range | −55 to +175 °C - enables placement near high-heat sources (e.g., engine bay ECUs) |
| ESD Withstand (ISO 10605) | ±30 kV air/contact discharge - exceeds automotive electronics immunity requirements |
| Package | SMC (DO-214AB) - JEDEC-registered, IPC7531-compliant footprint for automated assembly |
Pinout & Package
SM30T30CAY uses the SMC (DO-214AB) surface-mount package: 7.75–8.15 mm length × 5.55–6.25 mm width × 2.45 mm height, matte tin-plated leads, MSL Level 1, reflow-compatible per J-STD-020.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Cathode for unidirectional) | Bidirectional surge path terminal | Conducts in both polarities during overvoltage events; symmetric breakdown enables single-device protection of AC-coupled lines like LIN or differential CAN stubs |
| Cathode (Anode for unidirectional) | Bidirectional surge path terminal | Paired with Anode to form symmetrical clamping path; no polarity marking required on PCB layout |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive use across temperature, humidity, and mechanical shock per JESD47 |
| Low dynamic resistance (RD) | 34.5 mΩ - reduces clamping voltage rise under high di/dt surges, improving protection margin |
| High junction temperature rating | 175 °C max - allows mounting on hot PCB zones without derating, reducing need for thermal relief |
| JEDEC-registered SMC outline | Ensures mechanical compatibility with standard pick-and-place equipment and IPC7531 footprints |
| UL94 V0 flammability rating | Prevents flame propagation in enclosed automotive enclosures during fault conditions |
Applications
| Body Control Module (BCM) Power Input | CAN Transceiver Protection |
|---|---|
|
Use Scenario: 12 V battery line feeding BCM microcontroller and peripheral drivers exposed to load dump and jump-start transients. IC Role / Device Role / Timing Role: Primary clamping device placed upstream of DC-DC converter input, responding within nanoseconds to suppress >100 V spikes. Use Value: Limits input voltage to ≤42.1 V during ISO 7637-2 Pulse 5b (load dump), preventing regulator latch-up and MCU brownout. |
Use Scenario: Bidirectional protection of CAN_H/CAN_L differential pair against ESD and coupled transients in gateway modules. IC Role / Device Role / Timing Role: Symmetric TVS placed across differential lines, conducting equally on positive/negative surges without polarity bias. Use Value: Maintains signal integrity with <100 pF junction capacitance while surviving ±30 kV contact discharge per ISO 10605. |
| Infotainment Head Unit Power Rail | LIN Bus Node Protection |
|
Use Scenario: 5 V/3.3 V supply rail for display controller and audio codec subjected to board-level ESD and switching noise. IC Role / Device Role / Timing Role: Secondary protection stage after bulk filtering, absorbing residual fast transients that bypass LC filters. Use Value: 0.2 µA leakage avoids measurable quiescent current increase, critical for low-power sleep modes. |
Use Scenario: Single-wire LIN bus node (e.g., door module sensor) connected to vehicle harness with long cable runs. IC Role / Device Role / Timing Role: Low-capacitance bidirectional clamp on LIN line referenced to local ground, suppressing ISO 7637-2 Pulse 3a (−220 V). Use Value: Clamps to 42.1 V before LIN transceiver absolute maximum rating (typically 45 V) is exceeded, ensuring communication continuity. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ33CA | Lower peak power (400 W), higher clamping (64.5 V @ 6.5 A), SMA package | Not suitable for ISO 7637-2 Pulse 1/3a; limited to low-energy ESD-only roles | Select only for cost-sensitive non-automotive consumer designs with <100 V surge exposure |
| SMBJ33CA | 600 W peak power, 64.5 V clamping @ 9.3 A, SMB package, no AEC-Q101 | Lacks automotive qualification and fails ISO 7637-2 Pulse 3a (−220 V) compliance | Acceptable for industrial control panels but not for OEM vehicle production |
Compared with SMAJ33CA and SMBJ33CA, SM30T30CAY provides 5× higher surge energy handling, 22 V lower clamping at rated current, and full AEC-Q101 validation-making it the sole choice for front-end protection in certified automotive ECUs.
Availability
SM30T30CAY is available at Aetrix Electronics and suitable for automotive body electronics, infotainment power management, and LIN/CAN network protection requiring stable component supply across multi-year vehicle production cycles.
Supply support for SM30T30CAY 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, designing and manufacturing microcontrollers, power devices, sensors, and analog ICs for automotive, industrial, and consumer markets.
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 harsh-temperature, high-reliability vehicle subsystems.
FAQ
What is the difference between SM30T30AY and SM30T30CAY?
SM30T30AY is unidirectional (anode-cathode polarity), intended for DC-biased lines like power rails; SM30T30CAY is bidirectional (symmetric terminals), designed for AC-coupled or differential signals such as CAN/LIN buses. Their VBR, clamping, and surge ratings are identical, but polarity handling differs.
Does SM30T30CAY require a heatsink in automotive applications?
No heatsink is required. The SMC package achieves Rth(j-a) ≈ 45 °C/W on a 2 cm² copper pad (per Figure 12), and its 175 °C max Tj allows direct mounting on standard FR4 PCBs-even in engine compartment locations-without thermal derating for single-pulse events.
Can SM30T30CAY protect against load dump per ISO 16750-2 Test B?
Yes. At Us = 87 V and tp = 400 ms, SM30T30CAY sustains the load dump waveform without degradation (see Figure 22), delivering >3000 W peak power and maintaining clamping below 45 V-well within the safe operating area of downstream 45 V-rated regulators and transceivers.
Is the SMC package of SM30T30CAY compatible with automated optical inspection (AOI)?
Yes. The matte tin-plated leads and JEDEC-registered SMC outline (Table 3) ensure consistent solder joint reflectivity and dimensional repeatability, enabling reliable AOI detection of bridging, tombstoning, and coplanarity defects in high-volume automotive PCB assembly lines.
SM30T30CAY 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):
- 26V
- Voltage - Breakdown (Min):
- 28.9V
- Voltage - Clamping (Max) @ Ipp:
- 42.1V
- Current - Peak Pulse (10/1000µs):
- 71.3A
- 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
SM30T30CAY FAQ
1.How can I place an order for SM30T30CAY through Aetrix?
Please submit a Request for Quotation (RFQ) for SM30T30CAY 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 SM30T30CAY reliable?
The price and inventory of SM30T30CAY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM30T30CAY is usually 5 days.
3.What payment methods are accepted for SM30T30CAY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM30T30CAY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM30T30CAY?
SM30T30CAY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM30T30CAY 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 SM30T30CAY?
For technical support, including SM30T30CAY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM30T30CAY requirements.
6.How does Aetrix verify that SM30T30CAY is sourced from the original manufacturer or authorized distributors?
All SM30T30CAY 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 SM30T30CAY meets industry standards.
7.What is the process for return or replacement of SM30T30CAY?
All SM30T30CAY units undergo pre-shipment inspection (PSI). If there is an issue with SM30T30CAY, 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 SM30T30CAY part is unused and in its original packaging.
Return procedure for SM30T30CAY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SM30T30CAY Tags
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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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