STMicroelectronics SMC30J10A

Overview

SMC30J10A from STMicroelectronics is a unidirectional transient voltage suppression (TVS) diode designed for high-energy ESD and surge protection in DC power lines and signal interfaces. It delivers 3000 W peak pulse power (10/1000 µs), clamps at 17 V (max) under 21.7 A surge, and features ultra-low leakage (0.2 µA at 25 °C) and 175 °C junction operation - deployed in industrial power supplies and automotive body control modules.

For engineers reviewing the SMC30J10A datasheet, SMC30J10A pinout, SMC30J10A application, or SMC30J10A equivalent, key selection criteria include clamping voltage (V_CL = 17 V), breakdown voltage range (11.4–12.6 V), thermal robustness (T_j max = 175 °C), and JEDEC-registered 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 per IEC 61000-4-2 (±30 kV air/contact) and electrical fast transients per IEC 61000-4-4 (4 kV level 4). Its unidirectional configuration enables DC-biased line protection without reverse conduction.

Dynamic resistance (R_D = 7.78 mΩ) and temperature coefficient (α_T = 7.8 × 10⁻⁴/°C) are specified to support accurate clamping voltage prediction across operating temperature (−55 to +175 °C) using V_CL(T_j) = V_CL(25 °C) × [1 + α_T(T_j − 25)].

Key Specifications

Pinout & Package

The SMC30J10A is housed in a JEDEC-standard SMC (DO-214AB) surface-mount package with two terminals: cathode (marked band) and anode. The matte tin-plated leads comply with J-STD-002 and support lead-free reflow (240–245 °C peak).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ10A and 1.5KE10A, SMC30J10A provides 5× higher surge power handling in an SMT-optimized package with 25× lower leakage and superior thermal performance - making it the preferred choice for next-generation industrial and automotive power interface protection.

Availability

SMC30J10A is available at Aetrix Electronics and suitable for industrial power supply protection, automotive body control modules, telecom DC feeder systems, and renewable energy charge controller interfaces requiring stable component supply and long-term lifecycle assurance.

Supply support for SMC30J10A 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, delivering intelligent power, analog, MEMS, and microcontroller solutions for industrial, automotive, and consumer markets.

The SMC30J series belongs to ST's high-power TVS portfolio, engineered specifically for robust ESD and surge immunity in harsh-environment DC power and data lines - emphasizing low leakage, high-temperature resilience, and JEDEC-compliant manufacturability.

FAQ

What is the maximum clamping voltage of SMC30J10A at 21.7 A?

The maximum clamping voltage (V_CL) is 17 V at 21.7 A peak pulse current (8/20 µs waveform), measured at T_j = 25 °C. This value increases with junction temperature per the α_T coefficient (7.78 × 10⁻⁴/°C), reaching ~18.2 V at 125 °C.

Can SMC30J10A be used in bidirectional signal lines?

No - SMC30J10A is unidirectional and must be installed with cathode toward the protected line. For bidirectional protection (e.g., USB, RS-485), use the complementary SMC30J10CA variant, which features symmetrical breakdown in both polarities.

Does SMC30J10A require derating above 70 °C ambient?

Yes - while rated for T_j up to 175 °C, power dissipation must be derated above T_amb = 70 °C per Figure 3 in DS8598. At 100 °C ambient with recommended PCB copper area, peak pulse power drops to ~2200 W for 10/1000 µs pulses.

Is the SMC30J10A RoHS and REACH compliant?

Yes - SMC30J10A is manufactured in ST's ECOPACK2-compliant facilities, meeting RoHS Directive 2011/65/EU and REACH Regulation (EC) No. 1907/2006, with no SVHC substances above threshold and full material declaration available upon request.