STMicroelectronics SMC30J30CA

Overview

SMC30J30CA from STMicroelectronics is a bidirectional transient voltage suppression (TVS) diode designed for high-energy ESD and surge protection in power and signal lines. It delivers 3000 W peak pulse power (10/1000 μs), clamps at 48.4 V (max) under 185 A surge, and operates up to 175 °C junction temperature - deployed in industrial power supplies, telecom interfaces, and automotive body control modules.

For engineers reviewing the SMC30J30CA datasheet, SMC30J30CA pinout, SMC30J30CA application, or SMC30J30CA equivalent, key selection criteria include bidirectional standoff voltage (30 V), low leakage (0.2 µA at 25 °C), JEDEC-registered SMC package compatibility, and IEC 61000-4-2 ±30 kV contact/air discharge compliance.

Technical Context

This planar-junction TVS diode uses silicon avalanche technology to provide fast response (<1 ns) to electrostatic discharge and electrical overstress events. Its bidirectional architecture enables symmetric clamping on AC-coupled or floating lines without polarity constraints.

It meets IEC 61000-4-4 level 4 (4 kV), exceeds IEC 61000-4-2 level 4 (±30 kV), and maintains stable clamping performance across -55 °C to +175 °C operating junction range - enabled by low dynamic resistance (48.2 mΩ) and temperature-compensated breakdown voltage (α_T = 9.9 × 10⁻⁴/°C).

Key Specifications

Pinout & Package

SMC30J30CA is housed in a JEDEC-registered SMC (DO-214AB) surface-mount package with matte tin-plated leads, optimized for automated assembly and thermal dissipation on FR4 PCBs with recommended 3.14 cm² copper area per lead.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ30CA and SAC30CA, SMC30J30CA uniquely combines 3000 W capability, 0.2 µA leakage, and ±5% VBR tolerance in an industry-standard SMC package - making it optimal for high-reliability 24 V/48 V power systems where clamping precision and thermal stability are critical.

Availability

SMC30J30CA is available at Aetrix Electronics and suitable for industrial power supplies, automotive body control modules, telecom surge interfaces, and smart meter communication ports requiring stable component supply and full lifecycle traceability.

Supply support for SMC30J30CA 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 microcontroller technologies for industrial, automotive, and consumer markets.

The SMC30J series belongs to ST's high-power TVS portfolio, engineered specifically for robust, high-temperature surge protection in mission-critical power conversion and connectivity systems where reliability under extreme electrical stress is non-negotiable.

FAQ

What is the maximum surge current SMC30J30CA can handle?

SMC30J30CA withstands up to 185 A peak pulse current under the standardized 10/1000 μs waveform, corresponding to its 3000 W peak pulse power rating. At the shorter 8/20 μs waveform, it supports up to 64.3 A - verified per IEC 61000-4-5 test conditions and documented in Table 2 of DS8598 Rev 8.

Is SMC30J30CA compatible with lead-free reflow soldering?

Yes - SMC30J30CA is qualified for lead-free reflow per J-STD-020 MSL Level 1, with a maximum peak temperature of 240–245 °C and 60-second exposure (max 90 s). Its matte tin plating and ECOPACK-compliant construction ensure reliable wetting and intermetallic formation without voiding or delamination.

How does temperature affect its clamping voltage?

Clamping voltage increases with junction temperature at a coefficient α_T = 9.9 × 10⁻⁴/°C. For example, at 125 °C, V_CL rises ~10% above its 25 °C value (48.4 V → ~53.2 V), calculated using V_CL(T_j) = V_CL(25 °C) × [1 + α_T × (T_j − 25)]. This is fully characterized in Figure 10 of DS8598.

Can SMC30J30CA replace unidirectional TVS diodes like SMC30J30A?

No - SMC30J30CA is bidirectional and intended for AC or floating lines; SMC30J30A is unidirectional and requires correct polarity placement relative to ground. Substitution would cause unintended conduction in DC-biased circuits. The marking "CA" explicitly denotes bidirectional configuration, confirmed in Table 6 of DS8598.