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STMicroelectronics SMCJ20A-TR
- Part No.:
- SMCJ20A-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SMCJ20A-TR.pdf
- Description:
- TVS DIODE 20VWM 42.8VC SMC
- Quantity:
- Payment:
- Shipping:
Inventory:5,693
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Product details
Overview
SMCJ20A-TR from STMicroelectronics is a unidirectional 1500 W transient voltage suppression diode designed for primary-level ESD and surge protection in DC power rails and signal lines. It features a 20 V standoff voltage (VRM), 22.2–23.4 V breakdown voltage (VBR) at 1 mA, 32.4 V clamping voltage (VCL) at 48 A (10/1000 µs), 0.2 µA leakage at 20 V, and operates up to 150 °C junction temperature - deployed in industrial power supplies and automotive body control modules.
For engineers reviewing the SMCJ20A-TR datasheet, SMCJ20A-TR pinout, SMCJ20A-TR application, or SMCJ20A-TR equivalent, key selection criteria include clamping voltage margin vs. protected IC VDD tolerance, peak pulse current capability under IEC 61000-4-4 level 4 (4 kV), thermal derating above 25 °C, and SMC package footprint compatibility with IPC7531 layout standards.
Technical Context
This TVS diode uses planar silicon junction technology optimized for low leakage (<0.2 µA at 25 °C) and stable VBR drift (αT = 10⁻⁴/°C), enabling reliable operation in high-temperature environments up to 150 °C. Its dynamic resistance (RD = 0.163 Ω) ensures minimal voltage overshoot during fast transients.
The device meets IEC 61000-4-2 (±30 kV contact/air discharge) and IEC 61000-4-4 level 4 (4 kV), with peak pulse power rated at 1500 W (10/1000 µs) and up to 10 kW (8/20 µs), making it suitable for front-end protection where low capacitance (<100 pF at 1 MHz) and fast response (<1 ns) are critical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRM) | 20 V - Maximum continuous DC operating voltage before conduction begins. |
| Breakdown Voltage (VBR) | 22.2–23.4 V at 1 mA - Confirmed threshold where avalanche conduction initiates reliably. |
| Clamping Voltage (VCL) | 32.4 V at 48 A (10/1000 µs) - Peak voltage seen by downstream circuit during worst-case surge. |
| Peak Pulse Power (PPP) | 1500 W (10/1000 µs) - Sustained energy absorption capacity without failure at 25 °C ambient. |
| Leakage Current (IRM) | 0.2 µA at 20 V, 25 °C - Negligible standby power loss and minimal impact on high-impedance sensing nodes. |
| Junction Temperature Range | −55 to +150 °C - Enables deployment in under-hood automotive and industrial motor drive environments. |
| Package | SMC (DO-214AB) - Standardized surface-mount outline per JEDEC MS-013AC, IPC7531 compliant. |
Pinout & Package
SMCJ20A-TR is housed in an SMC (DO-214AB) plastic package with two terminals: Cathode (marked band) and Anode. The package measures 5.55–6.25 mm in length (D), 7.75–8.15 mm in width (E), and 1.90–2.45 mm in height (A1), with matte tin-plated leads compatible with lead-free reflow (J-STD-020 MSL Level 1).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (banded end) | Surge return path / reference node | Connected to system ground or low-impedance return; conducts avalanche current during overvoltage events. |
| Anode | Protected line input | Connected to the line being protected (e.g., 24 V rail); blocks reverse current until VBR is exceeded. |
Key Features
| Feature | Design Value |
|---|---|
| Low leakage current | 0.2 µA at VRM = 20 V - Preserves battery life and avoids false triggering in always-on circuits. |
| High-temperature stability | VBR drift coefficient αT = 10⁻⁴/°C - Ensures predictable clamping behavior across −55 to +150 °C. |
| IEC 61000-4-2 compliance | ±30 kV air/contact discharge - Meets highest ESD immunity class for industrial and automotive ECUs. |
| Robust surge handling | 10 kW peak power (8/20 µs) - Withstands lightning-induced surges in telecom and PoE applications. |
| UL94 V0 flammability rating | Epoxy housing self-extinguishes within 10 s - Required for safety-critical power supply designs. |
Applications
| Industrial Power Supply Input Protection | Automotive Body Control Module (BCM) CAN Bus Line Protection |
|---|---|
|
Use Scenario: 24 V DC input stage of programmable logic controller (PLC) power supply exposed to load dump and inductive switching transients. IC Role / Device Role / Timing Role: Primary clamping device placed upstream of DC-DC converter input capacitor to limit transient voltage to <33 V. Use Value: Clamps 48 A surge (10/1000 µs) to 32.4 V, staying within 80% of typical 40 V-rated input capacitors' WVDC rating. |
Use Scenario: CAN_H/CAN_L lines in BCM subjected to ESD events during connector mating/unmating in vehicle assembly. IC Role / Device Role / Timing Role: Unidirectional TVS on each CAN line referenced to chassis ground, absorbing ±30 kV ESD pulses per IEC 61000-4-2. Use Value: Sub-1 ns response time and <100 pF capacitance prevent signal integrity degradation on 1 Mbps CAN FD bus. |
| Telecom AC/DC Adapter Surge Suppression | Smart Meter DC Rail Protection |
|
Use Scenario: Secondary-side 12 V output of wall-mounted telecom adapter exposed to conducted surges via mains coupling. IC Role / Device Role / Timing Role: Final-stage TVS on regulated output rail, shunting energy before reaching metering IC and display driver. Use Value: 1500 W (10/1000 µs) rating handles repeated 2 kV ring wave surges per IEC 61000-4-5 without degradation. |
Use Scenario: 3.3 V or 5 V microcontroller supply rail in utility smart meter subject to EFT bursts during grid switching. IC Role / Device Role / Timing Role: Localized TVS adjacent to MCU VDD pin, clamping fast transients before LDO input. Use Value: 0.2 µA leakage prevents measurable increase in sleep-mode current, preserving 10-year battery backup life. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ20A-TR | Lower PPP (600 W vs. 1500 W), same VRM/VBR/VCL, SMB package (smaller footprint, higher thermal resistance) | Not suitable for >1 kA surge events; limited to secondary-side or low-energy signal line protection | Select when board space is constrained and surge threat level is ≤1 kV IEC 61000-4-5. |
| 1.5KE20A | Through-hole DO-201 package, identical electrical specs but higher RD (0.22 Ω) and no MSL-1 rating | Requires wave soldering; unsuitable for mixed-technology SMT-only production lines | Select only for legacy through-hole designs or prototyping where reflow compatibility is not required. |
Compared with SMBJ20A-TR and 1.5KE20A, SMCJ20A-TR delivers superior surge robustness in compact SMT form, supports automated reflow assembly per J-STD-020, and maintains lower clamping voltage under high-current transients due to reduced dynamic resistance.
Availability
SMCJ20A-TR is available at Aetrix Electronics and suitable for industrial power supplies, automotive body control modules, telecom adapters, and smart meter designs requiring stable component supply with full traceability and long-term lifecycle support.
Supply support for SMCJ20A-TR 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 power management, analog, MEMS, and microcontrollers for industrial, automotive, and consumer markets.
SMCJ series TVS diodes belong to ST's transient protection product line, engineered specifically for high-reliability DC rail and interface line protection where low leakage, high-temperature operation, and IEC-compliant surge immunity are mandatory.
FAQ
What is the maximum clamping voltage of SMCJ20A-TR under a 10/1000 µs 48 A surge?
The maximum clamping voltage is 32.4 V at 48 A for a 10/1000 µs waveform, measured at Tj = 25 °C. This value increases linearly with junction temperature at a rate defined by αT = 10⁻⁴/°C, reaching ~34.2 V at 125 °C per the VCL(Tj) formula in DS1284 Rev 11.
Can SMCJ20A-TR be used for bidirectional signal line protection?
No - SMCJ20A-TR is unidirectional and conducts only in reverse bias. For bidirectional protection (e.g., RS-485, USB D+/D−), use SMCJ20CA-TR, which has symmetrical clamping in both polarities and identical VBR/VCL ratings.
Does SMCJ20A-TR meet RoHS and REACH requirements?
Yes - SMCJ20A-TR is manufactured in ST's ECOPACK2-compliant facilities and conforms to RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006, with full material declarations available upon request via ST's quality portal.
What is the recommended PCB footprint for SMCJ20A-TR?
The recommended footprint follows IPC7531 and JEDEC MS-013AC standards: pad length 5.11 mm, pad width 3.14 mm, center-to-center spacing 8.19 mm, with 1.54 mm solder mask opening per pad - matching the SMC package mechanical data in DS1284 Rev 11 page 6.
SMCJ20A-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AB, SMC
- Series:
- SMCJ, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 20V
- Voltage - Breakdown (Min):
- 22.2V
- Voltage - Clamping (Max) @ Ipp:
- 42.8V
- Current - Peak Pulse (10/1000µs):
- 234A (8/20µs)
- Power - Peak Pulse:
- 1500W (1.5kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMC
SMCJ20A-TR FAQ
1.How can I place an order for SMCJ20A-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for SMCJ20A-TR 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 SMCJ20A-TR reliable?
The price and inventory of SMCJ20A-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMCJ20A-TR is usually 5 days.
3.What payment methods are accepted for SMCJ20A-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMCJ20A-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMCJ20A-TR?
SMCJ20A-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMCJ20A-TR 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 SMCJ20A-TR?
For technical support, including SMCJ20A-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMCJ20A-TR requirements.
6.How does Aetrix verify that SMCJ20A-TR is sourced from the original manufacturer or authorized distributors?
All SMCJ20A-TR 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 SMCJ20A-TR meets industry standards.
7.What is the process for return or replacement of SMCJ20A-TR?
All SMCJ20A-TR units undergo pre-shipment inspection (PSI). If there is an issue with SMCJ20A-TR, 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 SMCJ20A-TR part is unused and in its original packaging.
Return procedure for SMCJ20A-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMCJ20A-TR Tags
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