Littelfuse Introduces TPSMD-FL TVS Diodes for Automotive Load-Dump Protection

Littelfuse has introduced the TPSMD-FL Series of automotive TVS diodes for protecting 12 V vehicle electronics against load-dump transients. The new devices use the company’s FlatSuppressX technology and are designed to meet ISO 7637-2 Pulse 5b requirements while keeping clamping voltage low during high-energy surge events.

The series is rated for 3000 W peak pulse power and comes in a surface-mount DO-214AB package. The devices are also AEC-Q101 qualified for automotive use.

FlatSuppressX Changes the Clamping Characteristic

The main difference with the TPSMD-FL Series is the behaviour of the diode as transient current rises. Littelfuse uses an advanced foldback I-V characteristic to maintain a lower and flatter clamping voltage during a surge.

This is particularly relevant during an automotive load dump, where the voltage on the 12 V supply can rise sharply following a battery disconnection while the alternator is charging. Keeping the clamping voltage under control reduces the voltage presented to electronics further downstream.

Littelfuse says this characteristic can allow designers to meet ISO 7637-2 Pulse 5b requirements with fewer additional protection components. The TPSMD-FL Series is specifically intended for this type of transient on 12 V automotive power networks.

3000 W Peak Pulse Power

Alongside its load-dump capability, the new series is rated for 3000 W peak pulse power dissipation. It also provides ESD protection up to 30 kV for both air and contact discharge under IEC 61000-4-2.

The devices are supplied in the DO-214AB surface-mount package, giving designers a compact option for high-energy transient protection. Target applications include zonal control modules, powertrain electronics, infotainment systems and body control modules.

TPSMD-FL Series devices are available now in tape-and-reel quantities of 3,000, with samples available through authorised Littelfuse distributors.

Learn more and read the original announcement at the Littelfuse website.

Technology Overview

A TVS diode protects electronics by conducting when a transient pushes the supply voltage beyond a defined level. Automotive load-dump events can produce high-energy surges on the vehicle supply, making both surge capability and clamping voltage important when selecting protection for downstream electronics.

Frequently Asked Questions

What is different about the Littelfuse TPSMD-FL Series?

The TPSMD-FL Series uses Littelfuse FlatSuppressX technology with a foldback I-V characteristic that maintains a low, stable clamping voltage during high-energy transient events.

Which automotive load-dump standard does the TPSMD-FL Series address?

The devices are designed for ISO 7637-2 Pulse 5b load-dump protection in 12 V automotive electrical systems.

What surge and ESD protection does the TPSMD-FL Series provide?

The series is rated for 3000 W peak pulse power and provides IEC 61000-4-2 ESD protection up to 30 kV for both air and contact discharge.