Melexis Launches Advanced Performance Temperature Sensor with Infrared Technology Innovation for Smart Induction Cooktop Control
Introduction: Breakthrough in Non-Contact Temperature Measurement
January 20, 2025, Tessenderlo, Belgium — Global microelectronics engineering company Melexis has announced the launch of MLX90617, a non-contact infrared temperature sensor chip designed specifically for induction cooktops. This chip employs innovative optical filtering technology that can penetrate through the ceramic panel of induction cooktops to precisely measure the temperature at the bottom of cooking vessels. This breakthrough technology not only greatly enhances the precision of cooking control but also significantly improves the safety of induction cooktop usage, thereby substantially enhancing the overall user experience.
Overcoming Traditional Limitations
Due to limitations in existing technology, traditional induction cooktops primarily rely on temperature monitoring from the back of the ceramic glass plate, which to some extent affects the precision of temperature control. To overcome this limitation, Melexis has successfully developed an advanced and cost-effective MLX90617 solution that can penetrate the ceramic glass plate of induction cooktops to accurately measure the temperature at the bottom of cooking vessels in real-time.
Working Principle
MLX90617 employs precise optical filtering technology optimized for induction cooktop ceramic glass plates. This technology accurately captures infrared radiation from the bottom of cooking vessels that penetrates through the ceramic glass plate and effectively filters out infrared interference emitted by the ceramic glass plate itself through advanced algorithms, thereby ensuring the accuracy and reliability of temperature measurements.
Operational Methodology
MLX90617 is designed to work in conjunction with another non-contact temperature sensor chip (such as MLX90614 or MLX90632), both installed beneath the ceramic surface of the induction cooktop. Additionally, LED and light sensor chips can be optionally configured to achieve in-situ emissivity measurement, further enhancing measurement accuracy.
To accurately determine the temperature of cooking vessels, MLX90617 primarily measures radiation emitted from the bottom of the cooking vessel, while the other sensor chip monitors radiation generated by the ceramic glass plate and the sensor itself. Meanwhile, the integrated LED and light sensor chips measure the reflectivity of the cooking vessel to calculate its emissivity. Through efficient real-time processing algorithms, the system can accurately calculate the temperature at the bottom of the cooking vessel while effectively eliminating interference from the ceramic surface and the sensor chip’s own radiation.
Compared to the standard method used by traditional induction cooktops that measure the ceramic glass temperature (Tglass), MLX90617 employs advanced optical filtering technology to penetrate the glass in real-time and directly measure the temperature at the bottom of the cooking vessel (Tpot). Comparative results show that the measurements provided by MLX90617 are significantly closer to the actual temperature of the cooking vessel, fully demonstrating its exceptional temperature measurement accuracy.
Improving Induction Cooktop Design
By integrating Melexis’s MLX90617 chip, induction cooktop manufacturers can create an advanced solution that significantly improves product accuracy and optimizes the end-user cooking experience.
The sensor chip directly monitors the temperature at the bottom of the cooking vessel rather than the glass surface temperature, allowing the electronic control system of the induction cooktop to more precisely understand the food temperature. This feature is particularly beneficial for cooking operations that require adjustments within precise temperature ranges. Additionally, the chip features temperature limit detection functionality, effectively enhancing system safety and promoting the development of more advanced automatic cooking systems.
Technical Specifications
The MLX90617 chip comes with a factory-preset wide operating temperature range (0°C to 125°C) and is designed for measuring cookware temperatures in the range of 70°C to 250°C. It adopts the industry-standard TO39 package, supports 5V power supply voltage, and easily integrates into induction cooktop designs through the SMBus digital interface.
The MLX90617 chip highly integrates an infrared thermopile detection element, signal conditioning ASSP, low-noise amplifier, 17-bit ADC, and high-performance DSP unit within the TO39 package, achieving high-precision and high-reliability temperature measurement functionality.
In-Depth Development
“Initially, we developed MLX90617 in response to customer needs, but faced numerous challenges when processing weak short-wave infrared signals, which at one point made us question its feasibility,” Melexis Marketing Manager Joris Roel candidly shared. “However, after in-depth research, development, and application testing, we not only successfully overcame these obstacles but also launched a solution that both meets customer needs and is economical, efficient, and easy to use.”
