onsemi MR2835SKG

Overview

MR2835SKG from onsemi is a high-energy automotive overvoltage transient suppressor diode designed for reverse-avalanche clamping in 12 V vehicle electrical systems. It features 23 V DC blocking voltage, 400 A non-repetitive peak surge current, and 24–32 V breakdown voltage at 100 mA, protecting ignition, fuel injection, and autoblocking modules against load dump transients.

For engineers reviewing the MR2835SKG datasheet, pinout, applications, or equivalent options, key selection criteria include its 1.0 °C/W junction-to-case thermal resistance, 62 A peak repetitive reverse surge current (10 ms time constant), and Pb-free Top Can package optimized for high-power transient suppression in under-hood environments.

Technical Context

This device operates exclusively in reverse-biased avalanche mode as a power zener-type transient suppressor-not as a rectifier or forward-switching element. Its clamping behavior is defined by a 24–32 V breakdown range at 100 mA and extends to 40 V at 80 A/85°C/80 µs pulse, with a positive 0.09 %/°C breakdown voltage temperature coefficient.

Thermal design relies on direct case-mounting: the Top Can package delivers 1.0 °C/W junction-to-case resistance, enabling dissipation of up to 2800 W peak reverse power (at TC = 25°C, 10 ms time constant) while maintaining TJ between −40°C and +150°C under specified mechanical stress limits.

Key Specifications

Pinout & Package

Package: Top Can Button (Case 460-02), metal-can surface-mount package with cathode marked on top button. Dimensions: 9.1–9.5 mm (A) × 9.5–9.9 mm (B) × 5.2–5.6 mm (C); weight ≈ 1.78 g.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar overvoltage transient suppressor applications.

Compared with MR2835SKG, SMCJ24A offers smaller footprint but lower surge robustness and higher parasitic capacitance, while TPSMD24 trades thermal efficiency for SMD manufacturability-neither matches MR2835SKG's 400 A single-pulse rating or 1.0 °C/W thermal path for under-hood primary clamping.

Availability

MR2835SKG is available at Aetrix Electronics and suitable for automotive engine control units, fuel injection systems, ignition coil drivers, and autoblocking system interfaces requiring stable component supply with full AEC-Q101 qualification traceability.

Supply support for MR2835SKG 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensor, and automotive electronics.

The MR2835SKG belongs to onsemi's automotive transient suppressor product line, engineered specifically for ISO 7637-2 Load Dump Pulse 5a compliance in 12 V vehicle architectures.

FAQ

What is the primary function of the MR2835SKG in automotive circuits?

The MR2835SKG functions as a high-energy reverse-biased avalanche diode that clamps destructive overvoltage transients-especially ISO 7637-2 Load Dump pulses-on 12 V battery rails. It protects downstream electronics like ECUs and injectors by conducting surge current to ground once voltage exceeds its 24–32 V breakdown range. Its Top Can package and 1.0 °C/W thermal resistance make MR2835SKG uniquely suited for primary-level protection in harsh under-hood locations.

Does the MR2835SKG meet automotive qualification standards?

Yes, the MR2835SKG is qualified to AEC-Q101 for stress testing including temperature cycling, humidity bias, and high-temperature operating life. Its design targets ISO 7637-2 Pulse 5a (load dump) compliance, with validated performance at 400 A non-repetitive surge and operation from −40°C to +150°C. The MR2835SKG's mechanical stress limits (e.g., 150 N compression, 250 N shear) further confirm its suitability for automotive mounting environments.

How is the MR2835SKG mounted and thermally managed?

The MR2835SKG uses a Top Can Button package where the anode is the metal case base and must be soldered directly to a large copper pour or heatsink. Its 1.0 °C/W junction-to-case thermal resistance depends entirely on this low-impedance thermal path. Mounting requires 260°C belt furnace profile (10 s max), and mechanical limits specify 150 N compression and 250 N shear force tolerance. Proper MR2835SKG installation ensures peak reverse power dissipation remains within 2800 W at 25°C case temperature.

What is the significance of the +0.09 %/°C breakdown voltage temperature coefficient for MR2835SKG?

The +0.09 %/°C V(BR) temperature coefficient means the MR2835SKG's clamping voltage increases predictably with junction temperature-e.g., rising ~0.7 V from 24 V at −40°C to ~26.5 V at +125°C. This positive drift improves system safety margin at high temperatures by preventing premature conduction during normal warm operation while still guaranteeing clamping action during transients. Designers use this coefficient to validate MR2835SKG's voltage window across full automotive temperature ranges.

Can MR2835SKG be used in 24 V commercial vehicle systems?

No, the MR2835SKG is rated for 23 V DC blocking and 24–32 V breakdown-optimized for 12 V automotive systems. Its 400 A surge rating assumes 12 V baseline; in 24 V systems, load dump amplitudes scale higher and require devices like MR2840SKG (40 V breakdown) or SM8S33A. Using MR2835SKG in 24 V applications risks premature conduction, thermal runaway, or failure to clamp beyond its energy rating. Always match MR2835SKG to 12 V architecture requirements.