High Speed Inductive Position Sensor with Differential Outputs for Safety-Critical EV Motor Position Monitoring

Published  June 16, 2022   0
High Speed Inductive Position Sensor

Microchip Technology Inc. has announced the new LX34070 IC that includes differential outputs, fast sample rates, and features that make it functional-safety-ready for ISO 26262 compliance in the Automotive Safety Integrity Level–C (ASIL–C) classification. Built for EV motor control applications, this position sensor solution offers numerous advantages compared to magnetic resolvers and Linear Voltage Differential Transducers (LVDTs), at a fraction of the cost. This IC is offered in a 14-pin TSSOP package with AEC-Q100 certification to grade 0 with an extended operating range (-40°C to +160°C) making it suitable for a wide range of commercial, industrial, medical, and/or automotive sensor applications.

This device uses PCB traces to both generate a magnetic excitation signal and detect the presence of a metal target positioned within the generated magnetic field. The advantage of this is a magnetic field sensor that does not require magnets, delivers higher accuracy, and is extremely immune to stray magnetic fields. For remote applications, this device is programmed through a power line VIN signal and verified from one of the output signals, eliminating the need for additional pins and signals. Moreover, in an embedded application where the sensor is on the same PCB as other microcontrollers, this device can be calibrated via digital signals.

Key Features

  • AEC-Q100 Grade 0 Certification

  • ISO26262 ASIL C(D) SEOOC Compliant

  • Built-in Oscillator for Driving Primary Coil

  • Two Independent Analog Channels With Demodulation

  • Automatic Gain Control Maximizes Resolution over Large Target Air gaps Ranges

  • 4.5V to 5.5V Input Range with Protection Up to 18V

  • Differential Output Buffers with Accurate Common-Mode Level and Protection Circuitry Against Output Shorts

  • Calibration Through VIN or GPIO

  • Detection of Faults at the Exciter Coil Pins and Receive Coil Pins

  • Power Supply and Ground Loss Detection

  • -40°C to 150°C Operation