Position sensors reinvented for mainstream automotive applications

Melexis has expanded its portfolio of non-contact position sensors with two new devices which complement the current MLX90364/5/6/7 products. The MLX90421 and MLX90422 are based on the company’s Triaxis high-accuracy magnetic sensing technology. They have the same main features as the existing devices but with further enhancements included. Designed for usage in cost-sensitive automotive applications, including pedal positioning, powertrain actuators, fuel level gauges and transmission systems, though also ideal for industrial implementations, these ICs have excellent capabilities in terms of functional safety and EMC characteristics. They also support elevated temperature operation.

As well as a magnetic sensing element, the new position sensing ICs feature built-in data conversion and digital signal processing and a programmable output stage driver. They can be configured for precisely determining position both rotationally or linearly. The MLX90421 offers a ratiometric analog or PWM output, while the MLX90422 delivers a SENT output according to SAE J2716.

The expansive -40C to 160C ambient temperature range indicates that they can be deployed within vehicles that lack the heat dissipation commonly found in engine bays, such as HEV and full EVs. With full adherence to ISO26262 functional safety guidelines, through the SEooC approach, the sensor IC supports the ASIL-B level. To assure first-time-right EMC testing, the new ICs provide similar performance to the company's established MLX9037x product family. Only one test cycle is required, meaning design work can be performed quicker, and the associated engineering costs are kept to a minimum. The improved AMR, such as output protection of -18V/34V and supply protection of -18V/37V, lessens the risk of electrical overstress.

The devices can be furnished with a single die in either a SOIC-8 package format or a PCB-less DMP-4. These options are backwards compatible with the company’s past devices, thereby offering drop-in replacements. A fully redundant dual die TSSOP-16 package is also offered for safety-critical situations needing system redundancy.