Melexis claims the first automotive-grade surface-mount (SMD) far-infrared (FIR) temperature sensor designed for temperature monitoring of critical components in electric vehicle (EV) powertrain applications. These include inverters, motors, and heating, ventilation, and air conditioning (HVAC) systems.
The MLX90637 offers several advantages over negative temperature coefficient (NTC) thermistors that have traditionally been used in these systems, where speed and accuracy are critical, Melexis said.
These advantages include eliminating the need for manual labor associated with NTC solutions thanks to the SMD packaging, which supports automated PCB assembly and delivers cost savings. In addition, the FIR temperature sensor with non-contact measurement ensures intrinsic galvanic isolation that helps to enhance EV safety by separating high- and low-voltage circuits, while the inherent electromagnetic compatibility (EMC) eliminates typical noise challenges associated with NTC wires, the company said.
Key features include a 50° field of view, 0.02°C resolution, and fast response time, which are suited for applications such as inverter busbar monitoring where temperature must be carefully managed. Sleep current is less than 2.5 μA. and the ambient operating temperature range is -40°C to 125°C.
The MLX90637 also simplifies system integration with a 3.3-V supply, factory calibration (including post calibration), and an I2C interface for communication with a host microcontroller, including a software-definable I2C address via an external pin. The AEC-Q100-qualified sensor is housed in a 3 × 3-mm package.