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STMicroelectronics SM30T19AY
- Part No.:
- SM30T19AY
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SM30T19AY.pdf
- Description:
- TVS DIODE 16VWM 26VC SMC
- Quantity:
- Payment:
- Shipping:
Inventory:6,982
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Product details
Overview
SM30T19AY from STMicroelectronics is an AEC-Q101-qualified unidirectional automotive TVS diode in SMC package, designed to clamp transient surges up to 3000 W (10/1000 µs) and 55.7 A peak pulse current while maintaining 26 V clamping voltage at 10/1000 µs. It delivers 18.7–19.6 V breakdown voltage at 1 mA, 0.2 µA max leakage at 25 °C, and operates up to +175 °C junction temperature - deployed in 12 V automotive power line protection against ISO 7637-2 Pulse 1, 2a, 3a, and 3b transients.
For engineers reviewing the SM30T19AY datasheet, SM30T19AY pinout, SM30T19AY application, or SM30T19AY equivalent, key selection criteria include clamping voltage under 10/1000 µs surge, unidirectional polarity for DC rail protection, SMC package thermal performance on FR4 PCB, and compliance with ISO 10605 ±30 kV ESD (150 pF/330 Ω) and ISO 7637-2 load dump immunity.
Technical Context
This device uses planar silicon avalanche technology to achieve low dynamic resistance (17.1 mΩ) and stable breakdown voltage drift coefficient (αT = 10 × 10−4/°C), enabling predictable clamping across −55 °C to +175 °C operating range. Its unidirectional configuration supports cathode-to-rail placement for reverse-polarity and load-dump suppression on positive supply lines.
The SMC package provides JEDEC-registered mechanical outline with matte tin lead finish, MSL Level 1 rating, and validated thermal impedance (Zth(j-a)) down to ~40 °C/W on recommended 3.14 cm² copper area - critical for sustained surge energy dissipation without thermal runaway during repetitive ISO 7637-2 pulses.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Breakdown Voltage (VBR) | 18.7–19.6 V at IBR = 1 mA - defines minimum trigger threshold before clamping activation |
| Clamping Voltage (VCL) | 26 V at IPP = 115 A (10/1000 µs) - maximum voltage seen by protected circuit during worst-case surge |
| Peak Pulse Power (PPP) | 3000 W (10/1000 µs) - energy-handling capacity for standard automotive surge waveforms |
| Leakage Current (IR) | 0.2 µA at VRM = 16 V, 25 °C - ensures minimal standby power loss in always-on vehicle modules |
| Junction Temperature (Tj) | −55 to +175 °C - enables deployment in engine bay, transmission control, or ADAS ECUs without derating |
| ESD Withstand (IEC 61000-4-2) | ±30 kV contact & air discharge (150 pF/330 Ω) - exceeds automotive OEM level-4 requirements |
| Dynamic Resistance (RD) | 17.1 mΩ - determines VCL rise slope under high di/dt transients (VCL = VBR + RD × IPP) |
Pinout & Package
SM30T19AY is housed in a surface-mount SMC (DO-214AB) package with two terminals: anode and cathode. The package measures 5.55–6.25 mm × 7.75–8.15 mm × 2.45 mm max height, features matte tin-plated leads, and complies with IPC7531 footprint recommendations.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Transient return path | Connected to ground or low-side reference; completes surge current loop during clamping |
| Cathode | Protected line connection | Connected to 12 V rail or signal line; blocks reverse current until VBR exceeded |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive under-hood and chassis applications per stress test requirements |
| Low leakage current | 0.2 µA at 16 V ensures <1 µW standby power draw in always-on telematics modules |
| High-temperature operation | +175 °C Tj(max) enables direct mounting near power MOSFETs or DC-DC converters |
| ISO 7637-2 compliance | Withstands Pulse 1 (−150 V), Pulse 2a (+112 V), Pulse 3a (−220 V), Pulse 3b (+150 V) without degradation |
| JEDEC-registered SMC outline | Ensures mechanical compatibility with automated pick-and-place and reflow soldering processes |
Applications
| Engine Control Unit (ECU) Power Input | Body Control Module (BCM) CAN Bus Protection |
|---|---|
|
Use Scenario: Protects 12 V input rail of gasoline/diesel engine ECU against battery disconnection spikes and alternator load dump events. IC Role / Device Role / Timing Role: Unidirectional TVS placed between battery feed and input capacitor, clamping transients within 1 ns response time. Use Value: Limits voltage to ≤26 V during 150 ms load dump (ISO 16750-2 Test B), preventing damage to MCU, LDOs, and gate drivers. |
Use Scenario: Shields CANH/CANL differential pair in BCM from coupled transients induced by nearby high-current solenoid switching. IC Role / Device Role / Timing Role: Paired unidirectional TVS devices (one per line) referenced to local ground, suppressing common-mode surges. Use Value: Maintains CAN signal integrity by clamping to 26 V before transceiver overvoltage lockout triggers, avoiding bus-off states. |
| Advanced Driver Assistance Systems (ADAS) Camera Power | Electric Power Steering (EPS) Motor Driver Stage |
|
Use Scenario: Safeguards 12 V supply to front-facing ADAS camera module mounted behind windshield, exposed to HVAC-induced transients. IC Role / Device Role / Timing Role: Primary overvoltage clamp on main power rail, positioned upstream of DC-DC converter input filter. Use Value: Prevents latch-up or permanent damage to image sensor and ISP ASIC during ISO 7637-2 Pulse 3a (−220 V) events. |
Use Scenario: Protects H-bridge gate driver ICs and sense resistors in EPS motor control unit from inductive kickback during sudden torque cutoff. IC Role / Device Role / Timing Role: High-energy TVS connected across motor supply rails, absorbing flyback energy from 3-phase inverter switching. Use Value: Enables reliable operation at 175 °C ambient by sustaining 3000 W surge without thermal runaway or parameter shift. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional automotive TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18A | Lower PPP (400 W), higher VCL (29.2 V @ 13.7 A), SMA package | Limited to low-energy infotainment or lighting circuits; not suitable for ECU or EPS load dump | Select only for cost-sensitive non-safety systems where 3000 W surge immunity is unnecessary |
| 1.5KE18A | Higher VCL (27.5 V @ 109 A), axial DO-201 package, no AEC-Q101 qualification | Requires manual assembly; lacks automotive reliability validation and thermal performance on FR4 | Use only in legacy industrial designs - not approved for new automotive programs |
Compared with SMAJ18A and 1.5KE18A, SM30T19AY delivers 7.5× higher surge power handling, 1.5 V lower clamping voltage under identical 10/1000 µs conditions, and guaranteed AEC-Q101 qualification - making it the sole choice for ASIL-B/C power rail protection where failure could impact vehicle motion control.
Availability
SM30T19AY is available at Aetrix Electronics and suitable for engine control units, body control modules, ADAS camera power supplies, and electric power steering systems requiring stable component supply across multi-year automotive production cycles.
Supply support for SM30T19AY 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 management ICs, sensors, and discrete protection devices for automotive, industrial, and consumer markets.
SM30T19AY belongs to the SM30TY series of high-power automotive TVS diodes, engineered specifically for robust transient suppression in 12 V and 24 V vehicle electrical architectures compliant with ISO 7637-2, ISO 10605, and ISO 16750-2 standards.
FAQ
What is the maximum clamping voltage of SM30T19AY under a 10/1000 µs surge?
The maximum clamping voltage is 26 V at 115 A peak pulse current (10/1000 µs waveform), measured at Tamb = 25 °C. This value increases linearly with junction temperature using αT = 10 × 10−4/°C, reaching ~27.3 V at Tj = 125 °C per datasheet Equation 2.
Is SM30T19AY suitable for bidirectional signal line protection?
No - SM30T19AY is unidirectional and intended for DC power rail protection only. For bidirectional signal lines like CAN or LIN, use the companion part SM30T19CAY, which provides symmetrical clamping in both polarities and matches the same VBR, VCL, and surge ratings.
Does SM30T19AY require derating at elevated ambient temperatures?
Yes - its peak pulse power capability decreases with rising junction temperature, dropping from 3000 W at 25 °C to ~1800 W at 125 °C and ~1200 W at 175 °C, as shown in Figure 3 of DS8599. Layout must ensure adequate copper area (≥3.14 cm² per lead) to maintain thermal resistance below 40 °C/W.
How does SM30T19AY compare to standard SMAJ-series TVS diodes in automotive use?
SM30T19AY offers 7.5× higher peak pulse power (3000 W vs. 400 W), 175 °C rated junction temperature (vs. 150 °C), AEC-Q101 qualification (vs. commercial-grade), and lower dynamic resistance (17.1 mΩ vs. ~35 mΩ), making it suitable for safety-critical power rail protection where SMAJ devices would fail catastrophically under ISO 7637-2 Pulse 5b load dump.
SM30T19AY 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):
- 16V
- Voltage - Breakdown (Min):
- 17.8V
- Voltage - Clamping (Max) @ Ipp:
- 26V
- Current - Peak Pulse (10/1000µs):
- 115.4A
- 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
SM30T19AY FAQ
1.How can I place an order for SM30T19AY through Aetrix?
Please submit a Request for Quotation (RFQ) for SM30T19AY 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 SM30T19AY reliable?
The price and inventory of SM30T19AY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM30T19AY is usually 5 days.
3.What payment methods are accepted for SM30T19AY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM30T19AY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM30T19AY?
SM30T19AY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM30T19AY 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 SM30T19AY?
For technical support, including SM30T19AY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM30T19AY requirements.
6.How does Aetrix verify that SM30T19AY is sourced from the original manufacturer or authorized distributors?
All SM30T19AY 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 SM30T19AY meets industry standards.
7.What is the process for return or replacement of SM30T19AY?
All SM30T19AY units undergo pre-shipment inspection (PSI). If there is an issue with SM30T19AY, 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 SM30T19AY part is unused and in its original packaging.
Return procedure for SM30T19AY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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