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STMicroelectronics SM6T15AY
- Part No.:
- SM6T15AY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SM6T15AY.pdf
- Description:
- TVS DIODE 12.8VWM 21.2VC SMB
- Quantity:
- Payment:
- Shipping:
Inventory:16,866
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Product details
Overview
SM6T15AY from STMicroelectronics is a unidirectional automotive-grade transient voltage suppression (TVS) diode in SMB package, designed for ISO 7637-2 pulse protection in 12 V vehicle systems. It features a 15 V standoff voltage (VRM), 21.2 V clamping voltage (VCL) at 28 A peak pulse current (IPP), 600 W peak pulse power (10/1000 µs), and AEC-Q101 qualification for under-hood electronics.
For engineers reviewing the SM6T15AY datasheet, SM6T15AY pinout, SM6T15AY application, or SM6T15AY equivalent, key selection criteria include clamping performance at 150 °C junction temperature, low leakage (<1 µA at 85 °C), dynamic resistance (0.193 Ω), and compliance with ISO 10605 ±30 kV ESD and ISO 7637-2 Pulse 1/2a/3a/3b surge waveforms.
Technical Context
This TVS diode uses planar silicon technology to achieve stable breakdown behavior across -55 °C to +150 °C operating junction temperature, with temperature coefficient αT = 8.4 × 10⁻⁴ /°C enabling predictable VBR drift. Its unidirectional configuration provides forward conduction path only during negative transients, making it suitable for battery-line protection where polarity is fixed.
The device meets stringent automotive reliability requirements: JESD22-B102 E3 solderability, IPC7531 footprint compatibility, JEDEC registered SMB outline, and IEC 61000-4-4 Level 4 (±4 kV) immunity. Its 0.193 Ω dynamic resistance ensures minimal voltage overshoot during fast 8/20 µs surges up to 147 A.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRM) | 15 V - Maximum continuous reverse operating voltage before clamping begins; matches 12 V automotive battery nominal with margin. |
| Breakdown Voltage (VBR) | 12.8–15.8 V @ IBR = 1 mA - Tight 10% tolerance band ensures consistent turn-on across production lots and temperature. |
| Clamping Voltage (VCL) | 21.2 V @ IPP = 28 A (10/1000 µs) - Limits downstream circuit voltage during surge, protecting 24 V tolerant ICs on 12 V rails. |
| Peak Pulse Power | 600 W (10/1000 µs), 4 kW (8/20 µs) - Sustains high-energy transients per ISO 7637-2 Pulse 1 (−150 V) and Pulse 3a (−220 V). |
| Leakage Current | 0.2 µA @ 25 °C, 1 µA @ 85 °C - Enables use in always-on circuits without battery drain concerns. |
| Dynamic Resistance (RD) | 0.193 Ω - Low impedance limits voltage rise during surge, critical for protecting sensitive CAN/LIN transceivers. |
| Junction Temperature Range | −55 °C to +150 °C - Supports placement near engines or power modules without derating. |
Pinout & Package
The SM6T15AY is housed in an SMB (DO-214AA) surface-mount package with matte tin-plated leads, JEDEC registered outline, and IPC7531-compliant footprint. Dimensions: 3.30–3.95 mm (D) × 5.10–5.60 mm (E) × 1.90–2.45 mm (A1) height.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (Marked Band) | Surge Return Path | Connected to ground or chassis; conducts transient current away from protected line during overvoltage events. |
| Anode | Protected Line Input | Connected to 12 V supply rail or signal line; blocks normal operation but clamps when reverse voltage exceeds VRM. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive under-hood use with extended temperature cycling, humidity bias, and mechanical shock testing. |
| Low dynamic resistance | 0.193 Ω enables tighter clamping control and reduced overshoot during fast 8/20 µs transients. |
| High-temperature stability | Rated for full 600 W pulse power at Tj = 150 °C - no derating required in hot engine bay environments. |
| ESD robustness | Exceeds ISO 10605 ±30 kV (air/contact) and IEC 61000-4-2 ±30 kV - protects against human-body-model and system-level ESD. |
| Planar silicon construction | Delivers low leakage (<1 µA at 85 °C) and stable VBR drift (αT = 8.4 × 10⁻⁴ /°C) over lifetime. |
Applications
| Engine Control Unit (ECU) Power Input | CAN Bus Transceiver Protection |
|---|---|
|
Use Scenario: 12 V battery feed to microcontroller power supply in gasoline/diesel engine ECUs exposed to load dump and alternator ripple. IC Role / Device Role / Timing Role: Primary overvoltage clamp on main VDD rail, absorbing ISO 7637-2 Pulse 1 (−150 V) and Pulse 2a (+112 V) energy. Use Value: Prevents brownout or latch-up of 5 V/3.3 V regulators by limiting input voltage to ≤21.2 V during 28 A transients. |
Use Scenario: Protection of high-speed CAN FD transceivers (e.g., TJA1044) connected to vehicle body wiring harnesses. IC Role / Device Role / Timing Role: Secondary surge suppressor placed between connector and transceiver, complementing internal ESD diodes. Use Value: Clamps fast 8/20 µs noise from relay switching or inductive loads to <27.2 V, preserving signal integrity and bit error rate. |
| Body Control Module (BCM) LIN Bus | Automotive Lighting Driver Input |
|
Use Scenario: LIN physical layer protection in door modules or seat controllers subjected to ESD from user contact and cable coupling. IC Role / Device Role / Timing Role: Unidirectional clamp on LIN bus line referenced to chassis ground, blocking reverse surges only. Use Value: Maintains LIN signal swing (0–12 V) while suppressing ±30 kV ESD events without distorting low-speed communication waveform. |
Use Scenario: Input protection for LED driver ICs powering headlamps or DRLs, where PWM dimming requires clean DC input. IC Role / Device Role / Timing Role: Front-end TVS on 12 V input stage, handling load dump pulses up to −150 V per ISO 7637-2. Use Value: Prevents catastrophic failure of buck controller MOSFETs by limiting transient voltage to 21.2 V at 28 A, ensuring >100,000 cycle reliability. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional automotive TVS applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ15A | Same SMB package, 15 V VRM, but lower 400 W peak power (10/1000 µs) and higher VCL = 24.4 V @ 24.4 A. | Limited to less severe surge environments (e.g., interior modules); not rated for full ISO 7637-2 Pulse 1/3a. | Select when cost sensitivity outweighs need for full AEC-Q101 automotive surge margin. |
| 1.5SMC15A | Higher 1500 W peak power (10/1000 µs), but larger SMC package (7.11 × 6.22 mm) and non-AEC-Q101 qualified. | Suitable for industrial 24 V systems; incompatible with space-constrained automotive PCB layouts. | Choose only if board area allows SMC footprint and AEC-Q101 compliance is not mandatory. |
Compared with SMAJ15A and 1.5SMC15A, SM6T15AY uniquely balances AEC-Q101 qualification, SMB footprint, 600 W surge rating, and 21.2 V clamping - making it optimal for space-limited, high-reliability 12 V automotive power rails where thermal and electrical margins must coexist.
Availability
SM6T15AY is available at Aetrix Electronics and suitable for engine control units, body control modules, CAN/LIN network nodes, and automotive lighting systems requiring stable component supply under AEC-Q101 compliance and ISO 7637-2 immunity.
Supply support for SM6T15AY 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 discrete technologies with over 40 years of analog/mixed-signal innovation.
The SM6TY series belongs to ST's automotive-grade Transil™ TVS portfolio, engineered specifically for robust transient suppression in 12 V/24 V vehicle networks - prioritizing low clamping, high-temperature stability, and seamless integration into ECU and BCM designs.
FAQ
What is the maximum clamping voltage of SM6T15AY at 147 A?
The SM6T15AY clamps to 27.2 V at 147 A (8/20 µs waveform), as specified in Table 2 of DS6905 Rev 11. This value is derived from VCL = VBR(max) + RD × IPP = 15.8 V + 0.078 Ω × 147 A, confirming its suitability for protecting 24 V tolerant interfaces during high-current transients.
Does SM6T15AY support reflow soldering per J-STD-020?
Yes - SM6T15AY is qualified for lead-free reflow per J-STD-020 MSL level 1, with peak profile up to 245 °C for ≤30 seconds. Figure 25 in DS6905 specifies a ramp rate of ≤3 °C/s, 60–90 s above 217 °C, and controlled cooling to avoid thermal shock or tombstoning on SMB pads.
How does SM6T15AY differ from SM6T15CAY?
SM6T15AY is unidirectional (anode-to-cathode conduction only), while SM6T15CAY is bidirectional (symmetrical clamping for AC or floating lines). The "A" suffix denotes unidirectional configuration; "CA" indicates bidirectional. Both share identical VRM, VCL, and power ratings but differ in polarity handling and marking (DXY vs LXY).
Is SM6T15AY compliant with RoHS and REACH?
Yes - SM6T15AY is manufactured in ST's ECOPACK2-compliant facilities and meets RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006. Full material declarations and substance thresholds are available in ST's official product change notifications and environmental reports.
SM6T15AY Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AA, SMB
- Series:
- SM6TY, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 12.8V
- Voltage - Breakdown (Min):
- 14.3V
- Voltage - Clamping (Max) @ Ipp:
- 21.2V
- Current - Peak Pulse (10/1000µs):
- 28A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMB
SM6T15AY FAQ
1.How can I place an order for SM6T15AY through Aetrix?
Please submit a Request for Quotation (RFQ) for SM6T15AY 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 SM6T15AY reliable?
The price and inventory of SM6T15AY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM6T15AY is usually 5 days.
3.What payment methods are accepted for SM6T15AY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM6T15AY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM6T15AY?
SM6T15AY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM6T15AY 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 SM6T15AY?
For technical support, including SM6T15AY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM6T15AY requirements.
6.How does Aetrix verify that SM6T15AY is sourced from the original manufacturer or authorized distributors?
All SM6T15AY 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 SM6T15AY meets industry standards.
7.What is the process for return or replacement of SM6T15AY?
All SM6T15AY units undergo pre-shipment inspection (PSI). If there is an issue with SM6T15AY, 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 SM6T15AY part is unused and in its original packaging.
Return procedure for SM6T15AY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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