With PROFET Wire Guard, Infineon has provided developers with advanced wire protection for modern power distribution.
Compared to conventional fuses, the product family can emulate the stress characteristics of the wires much more accurately with an integrated and precise I²t wire protection curve, which can be selected from six implemented curves depending on the application requirements. Combined with other features, the integrated I²t wire protection accuracy enables wire harness optimisation when replacing mechanical relays and fuses.
The five PROFET Wire Guard devices come in the proven TSDSO-14 and TSDSO-24 packages. They offer full pin-to-pin compatibility within the family and high compatibility with PROFET +2 12V devices and are targeting currents of up to 27 A. To expand the current capabilities up to 36A, the product line-up will be further extended with an additional device coming in Q4 2025. The devices have a capacitive load switching (CLS) mode implemented to charge capacitive loads. An adjustable overcurrent detection threshold supports fast fault isolation from the power supply. The integrated automatic idle mode reduces current consumption during parking to typically 50 µA, while the output stage remains fully switched on. Built-in sequential diagnosis provides accurate application data across five addresses on a single pin, enabling application integrity testing for functional safety requirements and further wire harness optimisation during facelifts based on the analysis of the wire protection status during vehicle operation. The devices have been developed and are released as ISO 26262:2018 Safety Element out of context for safety requirements up to ASIL D.
To support the design-in process, the product family is integrated into the Infineon Automotive Power Explorer, which is available in the Infineon Developer Centre. This simulation tool supports, for example, the evaluation of the system protection capability of PROFET Wire Guard devices with a given wire and load profile. It also calculates the correct resistance values for the adjustable overcurrent detection threshold as well as the selection of the integrated I²t wire protection curves. The tool is also capable to calculate parameters like kILIS accuracy or power dissipation for the whole product family.
