STMicroelectronics STRVS185X02B

Overview

STRVS185X02B from STMicroelectronics is a unidirectional repetitive voltage suppressor (TVS) designed for clamping transient overvoltages in power semiconductor circuits. It delivers 185 V clamping voltage at 2 A peak pulse current, 128–158 V breakdown range (25–125 °C), 0.2 µA leakage at 25 °C, and operates up to 150 °C junction temperature in SMB package - deployed in flyback MOSFET protection where repetitive surges cause thermal stress.

For engineers reviewing the STRVS185X02B datasheet, STRVS185X02B pinout, STRVS185X02B application, or STRVS185X02B equivalent, key selection criteria include clamping voltage stability across temperature, low leakage at stand-off voltage, thermal resistance (13 °C/W junction-to-leads), and compliance with IEC 61000-4-2 level 4 (±15 kV air / ±8 kV contact discharge) and MIL-STD-883 HBM (25 kV).

Technical Context

This device functions as a voltage-clamped transient protector with defined dynamic resistance (2.5 Ω) and temperature-coefficient-adjusted breakdown voltage (αT = 10.8 × 10⁻⁴/°C). Its clamping behavior is characterized at three temperatures (25 °C, 85 °C, 125 °C), enabling accurate surge modeling in thermally stressed switching nodes.

The STRVS185X02B uses a silicon avalanche diode structure optimized for repetitive surge duty cycles - not single-event ESD - and exhibits stable V_CL vs. I_PP curves up to 10 A, with minimal degradation under repeated 2 A pulses per IEC 61000-4-5 level 4 testing.

Key Specifications

Pinout & Package

The STRVS185X02B is housed in an SMB (DO-214AA) surface-mount package with cathode indicated by a band. The device has two terminals: anode and cathode - polarity-critical for unidirectional clamping in DC-biased circuits.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar repetitive voltage suppression applications.

Compared with SMAJ180A and P6SMB180A, STRVS185X02B provides superior thermal robustness (150 °C Tj), lower leakage (0.2 µA), and verified clamping performance at 125 °C - making it the preferred choice for thermally constrained, high-reliability MOSFET protection.

Availability

STRVS185X02B is available at Aetrix Electronics and suitable for flyback converter design, IGBT snubber implementation, and auxiliary power supply protection requiring stable component supply across automotive-grade temperature ranges and long-lifecycle production programs.

Supply support for STRVS185X02B 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, and protection devices for industrial, automotive, and consumer markets.

The STRVSX series was developed specifically for repetitive overvoltage suppression in power semiconductor gate-drive and switching-node applications - targeting reliability under cyclic surge stress rather than single-event ESD.

FAQ

What is the maximum peak pulse current rating for STRVS185X02B?

The device is rated for 2 A peak pulse current (I_PP) per IEC 61000-4-5, with clamping voltage specified at this level (185 V). Its V_CL vs. I_PP curve remains stable up to 10 A in typical operation, but 2 A is the validated test condition for compliance and datasheet specification.

Does STRVS185X02B support bidirectional transient suppression?

No - STRVS185X02B is a unidirectional TVS diode, marked with a cathode band. It clamps only when the cathode is positive relative to the anode. For bidirectional protection, a separate symmetric device such as STRVS185X02D would be required, which is not offered in SMB package for this voltage grade.

How does the 10.8 × 10⁻⁴/°C voltage temperature coefficient affect design?

This α_T value means V_BR increases by ~1.08% per 10 °C rise above 25 °C. At 125 °C, V_BR reaches 158 V (from 128 V at 25 °C), ensuring predictable turn-on timing and avoiding premature conduction in high-temperature operation.

Can STRVS185X02B replace standard SMAJ or P6SMB series parts in existing layouts?

Yes - it uses the same SMB (DO-214AA) footprint and polarity marking. However, its lower leakage (0.2 µA vs. ≥1 µA) and extended 125 °C clamping validation provide measurable reliability gains in thermally demanding applications, justifying direct substitution where enhanced performance is needed.