STMicroelectronics SMA6T82AY

Overview

SMA6T82AY from STMicroelectronics is a unidirectional 600 W automotive-grade transient voltage suppressor (TVS) diode designed for ISO 7637-2 pulse protection in 12 V/24 V vehicle power networks. It features a 81.9 V minimum breakdown voltage (V_BR), 110 V maximum clamping voltage (V_CL) at 5.5 A (10/1000 µs), and 0.2 µA leakage current at 25 °C - enabling robust surge immunity in engine control units, body electronics, and ADAS sensor interfaces.

For engineers reviewing the SMA6T82AY datasheet, SMA6T82AY pinout, SMA6T82AY application, or SMA6T82AY equivalent, this part supports high-reliability automotive ESD and load-dump protection where junction temperature stability up to +150 °C, low dynamic resistance (2.22 Ω), and AEC-Q101 qualification are mandatory selection criteria.

Technical Context

This TVS operates as a unidirectional avalanche clamp, triggered when reverse voltage exceeds its specified V_BR range (70.0–86.0 V). Its planar silicon structure ensures stable V_CL performance across temperature (α_T = 10.5 × 10⁻⁴/°C) and repeatable response to ISO 10605 ESD pulses (±30 kV air/contact discharge) and ISO 7637-2 transients (Pulse 1: −150 V; Pulse 2a: +112 V; Pulse 3a: −220 V).

The device uses JEDEC DO-214AC (SMA) package with matte tin lead finish, rated for MSL Level 1 moisture sensitivity and compliant with IPC7531 footprint standards. Its thermal resistance (R_th(j-a)) is 4.5 °C/W on 1 cm² FR4 copper, supporting sustained operation under repeated 600 W (10/1000 µs) surges without thermal runaway.

Key Specifications

Pinout & Package

Package: JEDEC DO-214AC (SMA), surface-mount, single-diode configuration with cathode band marking. Dimensions: D = 2.25–2.90 mm, E = 4.80–5.35 mm, L = 0.75–1.50 mm, weight = 0.072 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMA6T82A and SMAJ85A, SMA6T82AY delivers verified AEC-Q101 compliance, 600 W surge rating, and 110 V clamping - making it the only option qualified for safety-critical 24 V automotive power domains requiring ISO 7637-2 Pulse 1/3a immunity and 150 °C junction operation.

Availability

SMA6T82AY is available at Aetrix Electronics and suitable for engine control units, ADAS camera power inputs, and electric power steering sensor interfaces requiring stable component supply across extended automotive production lifecycles.

Supply support for SMA6T82AY 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 automotive, industrial, and power discrete technologies with over 40 years of analog and protection device innovation.

SMA6TY belongs to ST's Transil™ automotive TVS family, engineered specifically for robust ISO 7637-2 and ISO 10605 compliance in harsh-temperature vehicle subsystems - prioritizing clamping precision, thermal resilience, and long-term parametric stability.

FAQ

What is the standoff voltage (V_RM) of SMA6T82AY?

The maximum repetitive reverse standoff voltage (V_RM) is 68 V, meaning the device remains non-conductive up to this voltage under normal operating conditions - critical for compatibility with 24 V nominal systems where transient-free operation must be maintained below battery overvoltage thresholds.

How does SMA6T82AY perform under high-temperature conditions?

At 85 °C, leakage current rises to 1 µA (still well below 5 µA typical for automotive TVS), and V_BR increases by 10.5 × 10⁻⁴/°C - resulting in ~79.2 V at 125 °C. Its +150 °C T_j rating ensures uninterrupted clamping function even in under-hood locations with ambient temperatures up to +105 °C.

Can SMA6T82AY replace SMA6T82A in existing designs?

Yes, SMA6T82AY is a direct drop-in replacement for SMA6T82A in terms of pinout, footprint, and electrical parameters - but adds AEC-Q101 qualification, enhanced ESD robustness (±30 kV), and guaranteed performance across automotive temperature and lifetime stress profiles not validated in the standard-grade variant.

What is the dynamic resistance (R_D) and why does it matter?

SMA6T82AY has a measured dynamic resistance of 2.22 Ω, calculated from V_CL vs. I_PP slope. This low value minimizes voltage overshoot during fast transients - e.g., reducing clamped voltage by ~12 V compared to a 5 Ω TVS at 5.5 A - directly improving margin for downstream 36 V-rated power ICs.