Melexis Launches MLX92342 Hall Switch with Under-100 µs Safety Signal

Melexis has introduced the MLX92342, a programmable two-wire Hall effect switch designed for PCB-less position sensing in automotive and industrial applications.

The sensor delivers a valid output and safety signal in less than 100 µs and has been developed according to ISO 26262 as a safety hardware element out of context, supporting ASIL B system design. Applications include seatbelt buckles, brake fluid level sensing, locks, flaps and motor-driven mechanisms.

The MLX92342 uses a two-wire current interface that changes its supply current according to the detected magnetic state. This allows the device to connect to an ECU without a local PCB, reducing wiring compared with conventional three-wire switches.

Fast Diagnostics for Safety-Related Applications

The MLX92342 includes on-chip diagnostics and a dedicated safe state, reported through a defined current level. The ECU can therefore distinguish faults from normal on/off sensor states.

Its under-100 µs valid signal is particularly useful in seatbelt buckle detection, where ECUs may read sensor status within short test windows. Melexis says the fast response reduces timing constraints during system checks and production testing.

Two diagnostic modes support different applications. Sequential mode is intended for switch and end-position detection, including seatbelt buckles, brake fluid level sensors and locks. Parallel mode provides faster magnetic updates for latch applications such as motor commutation in window lifters, valves and gear mechanisms.

Programmable Magnetic Sensing and PCB-Less Packaging

The MLX92342 supports magnetic latch, unipolar and omnipolar switching, with a magnetic range from 0.5 mT to 200 mT. Programmable parameters include switching thresholds, output polarity, diagnostic mode, retry period and temperature coefficient.

An optional Integrated Magnetic Concentrator (IMC) supports lateral magnetic sensing where mechanical packaging limits sensor placement. Package options include TSOT23-3L surface-mount, TO92-3L through-hole and a PCB-less TO92-3L variant with an integrated capacitor.

The sensor operates from 2.7 V to 28 V and is specified for ambient temperatures from −40°C to +150°C. Protection features include reverse supply voltage protection, thermal protection and undervoltage reset, with system-level ESD ratings of 15 kV contact discharge and 25 kV indirect discharge.

The MLX92342 is available now, alongside the MLX92341 locked, pre-programmed version.

Learn more and read the original announcement at melexis.com .

Technology Overview

The Melexis MLX92342 is a programmable two-wire Hall effect switch for remote position sensing. It supports PCB-less installation, a valid output and safety signal in under 100 µs, and integrated diagnostics for ASIL B system design. The sensor offers latch, unipolar and omnipolar operation, magnetic thresholds from 0.5 to 200 mT, and a 2.7–28 V supply range.

FAQs

How does the MLX92342 communicate with an ECU?

The sensor uses a two-wire interface, changing its supply current according to the magnetic state. A dedicated current level indicates the diagnostic safe state.

What functional safety capabilities does the MLX92342 provide?

The device was developed according to ISO 26262 as a safety hardware element out of context, supporting ASIL B system design. It includes on-chip diagnostics and delivers a valid safety signal in less than 100 µs.

What package options are available?

The MLX92342 is available in TSOT23-3L, TO92-3L and PCB-less TO92-3L packages, with an integrated capacitor in the PCB-less variant.