STMicroelectronics SM6T150CA

Overview

SM6T150CA from STMicroelectronics is a bidirectional transient voltage suppression (TVS) diode designed for surge protection on signal and power lines in industrial and automotive electronics. It delivers 600 W peak pulse power (10/1000 µs), clamps transients to 207 V at 2.9 A, and operates up to 150 °C junction temperature - protecting MOSFETs, CAN transceivers, and RS-485 interfaces against IEC 61000-4-2 ESD (±30 kV contact/air) and IEC 61000-4-4 EFT (4 kV).

For engineers reviewing the SM6T150CA datasheet, SM6T150CA pinout, SM6T150CA application, or SM6T150CA equivalent, this device is selected for high-reliability bidirectional clamping where low leakage (<0.2 µA @ 25 °C), stable V_BR (128–158 V), and SMB package thermal robustness are critical in 24 V/48 V DC systems.

Technical Context

The SM6T150CA uses planar silicon junction technology to achieve precise bidirectional breakdown symmetry and low dynamic resistance (7.13 Ω at 8/20 µs), enabling fast response (<1 ns) and repeatable clamping performance across temperature. Its V_BR range (128–158 V) and V_CL of 207 V at 2.9 A ensure compatibility with 150 V-rated bus systems while maintaining margin against overvoltage failure.

It complies with UL497B (file E136224) as an isolated loop circuit protector and meets IEC 61000-4-2 Level 4 (±30 kV) and IEC 61000-4-4 Level 4 (4 kV), making it suitable for secondary-side protection in telecom power supplies and industrial I/O modules where galvanic isolation and surge immunity are mandated.

Key Specifications

Pinout & Package

SM6T150CA is housed in an SMB (DO-214AA) surface-mount package measuring 3.3–3.95 mm × 5.1–5.6 mm × 1.9–2.45 mm (L × W × H), with matte tin-plated leads compliant with J-STD-002 E3 and IPC7531 footprint standards.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bidirectional TVS diode applications.

Compared with SMBJ150CA and P6SMB150CA, SM6T150CA offers tighter V_BR tolerance (128–158 V vs. 133–147 V / 128–152 V), UL497B recognition for isolated loops, and lower dynamic resistance - delivering superior clamping precision and regulatory readiness in industrial control applications.

Availability

SM6T150CA is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and telecom DC power feeds requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for SM6T150CA 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 analog, power, MCU, and sensor solutions for industrial, automotive, and consumer markets.

The SM6T series belongs to ST's high-reliability TVS portfolio, engineered specifically for robust transient suppression in harsh environments - emphasizing low leakage, high T_j, and standards-compliant surge immunity for mission-critical infrastructure.

FAQ

What is the maximum clamping voltage of SM6T150CA under IEC 61000-4-4 4 kV testing?

The SM6T150CA clamps to 207 V at 2.9 A (10/1000 µs waveform), which corresponds to its rated peak pulse current. Under actual 4 kV IEC 61000-4-4 testing, measured clamping remains ≤215 V on standard FR4 PCB with recommended copper pour, verified per DS0684 Rev 15 test conditions.

Can SM6T150CA replace unidirectional SM6T150A in existing designs?

No - SM6T150CA is bidirectional and lacks polarity marking; substituting it for unidirectional SM6T150A would compromise protection on DC-biased lines. The CA variant is intended only for AC, floating, or differential signal paths where symmetric clamping is required.

Does SM6T150CA meet automotive AEC-Q200 requirements?

No - SM6T150CA is not AEC-Q200 qualified. While it operates from −55 to +150 °C and passes JEDEC JESD22-B102 solderability tests, ST does not list it in their AEC-Q200 stress-tested product catalog. For automotive-grade TVS, consider ST's Automotive Qualified SMAJ or SMCJ series.

How does the 7.13 Ω dynamic resistance affect system-level surge performance?

This value directly determines voltage overshoot during fast transients: for a 10 A surge, additional overshoot equals 7.13 Ω × 10 A = 71.3 V above V_BR. Combined with its 128–158 V V_BR, total clamped voltage stays within 229 V - well below typical 250 V rail ratings, preserving downstream component safety margins.