Melexis launches fully integrated inductive switch chip

April 11, 2024, Tessenderlo, Belgium - Melexis, a global microelectronics engineering company, today officially launched the innovative Induxis® switch chip MLX92442. This single-chip solution can directly detect conductive targets due to its non-contact design, no magnets required, and excellent resistance to stray field interference. The product not only supports small module design, significantly reduces the number of components, but also excels in improving safety and electrification levels. Its wide range of applications include high-voltage interlocks, charging port covers, seat belts, hoods/trunks, gear sensing or wire-controlled brakes.

Traditional automotive safety latches and switches, such as door and trunk handles, seat belts, and brake light switches, often use mechanical contacts or magnetic switches, such as pushbutton switches, reed switches, or Hall effect sensors. However, these solutions often require modifying the design of the security target when applied, such as adding magnets, brackets, or physical protrusions to trigger the button.

Melexis' innovative inductive solution completely overturns this traditional model. Its unique technology can directly sense the actual safety target, such as seat belt buckle or door lock, without the assistance of magnets or button actuators. As long as the target is conductive, accurate and reliable detection can be achieved.

Melexis's innovation in position sensing technology brings many significant advantages. This technology eliminates traditional moving mechanisms and additional parts, making direct sensing operation more reliable and safer, and no longer relying on safety components that may be damaged or displaced. In addition, this innovative solution helps to simplify the bill of materials (BOM). Inductive non-contact operation is not only more reliable than traditional mechanical solutions and can resist wear and tear over time, but also can resist magnetic interference, ensuring stable system operation.

Cutting-edge design

The core advantage of the MLX92442 lies in its highly integrated and miniaturized standard package design. Compared with other inductive solutions, this solution is unique in that the internal coil and interface of the chip are fully integrated, so that developers no longer need to develop bulky PCB and coil solutions for their applications.

To meet the needs of different applications, the solution offers two flexible options: pinned VK package or surface mount SOIC package. Regardless of the package, the BOM is reduced from 3 components to 2 components (target + chip/coil) compared to existing solutions. Combined with the aforementioned magnet removal feature, this innovation helps produce a more sustainable and safer design than existing sensors on the market.

To ensure continuous reliable operation, the MLX92442 also integrates reverse supply voltage, undervoltage and thermal protection mechanisms, as well as advanced integrated self-diagnostics with dedicated safety modes.

Simplify integration

Melexis' inductive solution excels in simplifying integration, reducing BOM component count and significantly saving development time. It supports factory and end-of-line programming, making intelligent switch/latch operation a breeze, simply by defining the shape and movement of the application. Compared with traditional Hall effect solutions, this solution does not require magnetic simulation, which can shorten the development cycle (an advantage second only to the significant BOM savings).

In terms of assembly design, the MLX92442's standard package and the absence of magnets and brackets make system integration simpler. This design not only simplifies the supply chain, but also reduces the number of components, helping to shorten prototyping and production assembly time. In addition, since only the matching of inductive sensors and conductive safety elements within an air gap of up to 1.5mm needs to be considered, this solution also helps to maintain mechanical tolerances in assembly.

The MLX92442 features an industry-standard two-wire or three-wire interface, a wide operating voltage range of 3.5V to 18V, and an operating temperature range of 40°C to 150°C, while meeting ISO26262 ASIL A standards, greatly simplifying design considerations. For safety-critical applications that require redundancy, the MLX92442's inductive technology offers a highly reliable option with low design requirements that can operate alongside Hall-effect and mechanical solutions.

Ready for evaluation

“By adopting this new technology, our engineering team has successfully redefined end-position sensing, bringing numerous advantages to users,” said Minko Daskalov, Product Manager at Melexis. “Induxis® is designed to drive continued advancements in electrification and safety technologies, supporting key areas such as battery and hydrogen technologies for grid and electric vehicles. The MLX92442 fits all of these requirements perfectly.”

The MLX92442 is currently in pre-production and we provide Engineering B samples and evaluation kits.