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STMicroelectronics SMC50J18CA
- Part No.:
- SMC50J18CA
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SMC50J18CA.pdf
- Description:
- Linear IC's
- Quantity:
- Payment:
- Shipping:
Inventory:8,467
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Product details
Overview
SMC50J18CA from STMicroelectronics is a bidirectional transient voltage suppression (TVS) diode designed for high-energy surge protection in power and signal lines. It delivers 5000 W peak pulse power (10/1000 μs), clamps at 29.2 V (max) under 171 A surge current, and operates up to 175 °C junction temperature - enabling robust ESD and EFT protection in industrial power supplies and automotive body electronics.
For engineers reviewing the SMC50J18CA datasheet, SMC50J18CA pinout, SMC50J18CA application, or SMC50J18CA equivalent, key selection criteria include its 18 V standoff voltage, bidirectional polarity, low 0.2 µA leakage at 25 °C, IEC 61000-4-2 ±30 kV contact/air discharge compliance, and SMC package compatibility with IPC7531 footprints.
Technical Context
This planar-junction TVS diode uses silicon avalanche technology to provide fast response (<1 ns) to electrostatic discharge and electrical fast transients. Its bidirectional configuration allows symmetric clamping across both polarities without external polarity management, making it suitable for AC-coupled interfaces and ungrounded signal paths.
The device exhibits a dynamic resistance of 18.0 mΩ at 8/20 μs surges and maintains stable clamping voltage up to 175 °C, with thermal impedance optimized for FR4 PCBs using recommended copper land patterns. Its JEDEC-registered SMC package supports reflow soldering per J-STD-020 MSL level 1.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRM) | 18 V - maximum continuous reverse operating voltage before significant leakage begins |
| Breakdown Voltage (VBR min) | 20 V at 1 mA - guaranteed avalanche conduction onset under DC stress |
| Clamping Voltage (VCL max) | 29.2 V at 171 A (10/1000 μs) - peak line voltage seen by protected circuit during worst-case surge |
| Peak Pulse Power (PPP) | 5000 W (10/1000 μs) - energy-handling capacity for standard lightning-surge waveforms |
| Leakage Current (IRM) | 0.2 µA at 18 V, 25 °C - negligible standby power loss in battery-backed or high-impedance circuits |
| Junction Temperature Range | −55 °C to +175 °C - enables deployment in under-hood automotive, industrial motor drives, and outdoor power systems |
| ESD Robustness | ±30 kV contact & air discharge (IEC 61000-4-2) - exceeds Level 4 immunity requirements for end-equipment certification |
Pinout & Package
The SMC50J18CA is housed in a JEDEC-standard SMC (DO-214AB) surface-mount package with matte tin-plated leads, compatible with IPC7531 footprint recommendations and reflow profiles per J-STD-020.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Cathode-bar side) | Surge return path (bidirectional) | Marked terminal; functions as cathode for positive transients and anode for negative transients |
| Cathode (unmarked side) | Surge return path (bidirectional) | Unmarked terminal; functions as anode for positive transients and cathode for negative transients |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional surge clamping | Enables single-device protection of AC lines or floating differential signals without polarity constraints |
| Low dynamic resistance (18.0 mΩ) | Minimizes voltage overshoot during fast-rising transients, improving protection margin for downstream ICs |
| High junction temperature rating (175 °C) | Supports reliable operation in thermally constrained environments such as enclosed power converters and engine control units |
| JEDEC-registered SMC outline | Ensures mechanical compatibility with automated pick-and-place equipment and standard reflow processes |
| UL94 V0 flammability rating | Meets safety requirements for plastic-encapsulated components in certified end equipment |
Applications
| Industrial Power Supply Input Protection | Automotive Body Control Module (BCM) CAN Bus Lines |
|---|---|
|
Use Scenario: Protecting 24 V DC input rails against load dump and ISO 7637-2 pulses in programmable logic controllers and motor drives. IC Role / Device Role / Timing Role: Primary overvoltage clamp placed between input rail and ground, responding within <1 ns to suppress transients exceeding 100 V. Use Value: Limits peak rail voltage to ≤29.2 V during 171 A surges, preventing damage to upstream rectifiers and downstream DC-DC controllers. |
Use Scenario: Safeguarding bidirectional CAN_H/CAN_L differential pair against ESD events in vehicle door modules and lighting ECUs. IC Role / Device Role / Timing Role: Bidirectional TVS placed across CAN bus lines to clamp both polarities without disrupting differential signaling integrity. Use Value: Maintains <1.5 V common-mode noise margin during ±30 kV ESD strikes while adding <10 pF capacitance per line at 0 V bias. |
| AC-DC Adapter Secondary-Side Output Protection | Smart Meter Communication Interface (RS-485) |
|
Use Scenario: Securing isolated 12–24 V output rails of wall adapters against user-induced surges and coupling from primary-side transients. IC Role / Device Role / Timing Role: Low-leakage (0.2 µA) TVS connected from output to ground, minimizing quiescent power loss in energy-metering applications. Use Value: Clamps output to 29.2 V during 5000 W surges while sustaining 175 °C junction temperature during sustained overload conditions. |
Use Scenario: Protecting half-duplex RS-485 transceivers in utility smart meters exposed to field-installed wiring surges and lightning-induced coupling. IC Role / Device Role / Timing Role: Bidirectional TVS placed across A/B differential lines and to ground, meeting IEC 61000-4-4 Level 4 (4 kV) requirements. Use Value: Delivers 29.2 V clamping at 171 A with 18 mΩ dynamic resistance, preserving signal integrity up to 10 Mbps under surge stress. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18CA (ON Semiconductor) | Same 18 V VRM and bidirectional configuration, but rated for 400 W (not 5000 W); lower clamping voltage (29.2 V vs 29.2 V) but significantly reduced surge capacity | Intended for lower-energy ESD-only protection; unsuitable for IEC 61000-4-4 or lightning-survivable designs | Select only when system-level surge testing does not exceed 400 W and board space is constrained to SMA footprint |
| 1.5KE18CA (Littelfuse) | Higher 1.5 kW peak power (10/1000 μs), through-hole DO-201 package, 29.2 V clamping, but 175 °C Tj rating and 0.2 µA leakage match SMC50J18CA | Requires through-hole assembly; incompatible with automated SMT lines and dense PCB layouts | Choose only for legacy through-hole designs or where mechanical robustness outweighs SMT process efficiency |
Compared with SMAJ18CA and 1.5KE18CA, SMC50J18CA uniquely combines 5000 W surge capability, SMC surface-mount packaging, and full IEC 61000-4-2/4-4 compliance - making it the only option among the three qualified for high-reliability industrial and automotive SMT production.
Availability
SMC50J18CA is available at Aetrix Electronics and suitable for industrial power supply input protection, automotive body control module CAN bus lines, AC-DC adapter secondary-side output protection, and smart meter RS-485 interfaces requiring stable component supply across extended product lifecycles.
Supply support for SMC50J18CA 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 broad manufacturing and R&D infrastructure.
The SMC50J TVS series targets high-reliability surge protection in harsh-environment applications - specifically engineered for automotive power distribution, industrial SMPS inputs, and communication interface hardening where 175 °C operation and 5000 W surge immunity are mandatory.
FAQ
What is the maximum clamping voltage of SMC50J18CA under a 10/1000 μs surge?
The maximum clamping voltage (VCL) is 29.2 V at 171 A for a 10/1000 μs waveform, measured at 25 °C ambient. This value increases with junction temperature at a coefficient of 10⁻⁴/°C, reaching approximately 31.5 V at 175 °C junction temperature under the same current.
Is SMC50J18CA suitable for protecting RS-485 bus lines?
Yes - its bidirectional configuration, 29.2 V clamping voltage, and low 18.0 mΩ dynamic resistance make it effective for RS-485 differential pair protection. At 0 V bias, junction capacitance is below 100 pF, preserving signal integrity up to 10 Mbps in half-duplex configurations.
How does SMC50J18CA differ from unidirectional SMC50J18A?
SMC50J18CA provides symmetrical clamping for both positive and negative transients due to its bidirectional structure, while SMC50J18A clamps only in one direction and requires correct polarity orientation. The CA version adds no performance penalty - identical VBR, VCL, PPP, and leakage - but eliminates installation error risk in AC or floating circuits.
Does SMC50J18CA meet automotive qualification standards?
While not AEC-Q200 qualified as a standalone component, SMC50J18CA meets critical automotive-relevant requirements: 175 °C operating junction temperature, IEC 61000-4-2 ±30 kV ESD, IEC 61000-4-4 Level 4 (4 kV), and UL94 V0 flammability - enabling use in non-safety-critical automotive modules like body electronics and infotainment power rails.
SMC50J18CA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AB, SMC
- Series:
- SMC50J
- Packaging:
- Bulk
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 18V (Max)
- Voltage - Breakdown (Min):
- 20V
- Voltage - Clamping (Max) @ Ipp:
- 29.2V
- Current - Peak Pulse (10/1000µs):
- 171A
- Power - Peak Pulse:
- 5000W (5kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMC
SMC50J18CA FAQ
1.How can I place an order for SMC50J18CA through Aetrix?
Please submit a Request for Quotation (RFQ) for SMC50J18CA 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 SMC50J18CA reliable?
The price and inventory of SMC50J18CA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMC50J18CA is usually 5 days.
3.What payment methods are accepted for SMC50J18CA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMC50J18CA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMC50J18CA?
SMC50J18CA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMC50J18CA 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 SMC50J18CA?
For technical support, including SMC50J18CA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMC50J18CA requirements.
6.How does Aetrix verify that SMC50J18CA is sourced from the original manufacturer or authorized distributors?
All SMC50J18CA 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 SMC50J18CA meets industry standards.
7.What is the process for return or replacement of SMC50J18CA?
All SMC50J18CA units undergo pre-shipment inspection (PSI). If there is an issue with SMC50J18CA, 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 SMC50J18CA part is unused and in its original packaging.
Return procedure for SMC50J18CA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMC50J18CA Tags
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