MLX90411-D: A Cost-Optimized, Low-Noise Fan Motor Controller for Reliable Cooling Across Consumer and Industrial Applications

From gaming consoles and personal computers to refrigerators, uninterruptible power supplies (UPS), and energy storage systems (ESS), cooling fans play a critical role across a wide range of applications. Manufacturers serving these markets face a growing challenge: ensuring long-term reliability and durability while simultaneously addressing increasing pressure on system cost and acoustic performance. The MLX90411-D addresses these demands through a carefully optimized design that combines advanced motor control capabilities with Melexis’ well-established reputation for reliability and performance, all delivered in a cost-efficient solution.

At the heart of the MLX90411-D is an enhanced motor control algorithm that enables smoother start-up and shutdown behavior, reduced audible noise, and extended operational lifetime. An improved proportional–integral (PI) control loop ensures stable operation even at very low speeds—down to below 1000 RPM—while offering multiple start and stop profiles to suit diverse application requirements. In addition, the device introduces greater configurability through flexible speed-curve definition, allowing designers to set both minimum and maximum operating points. This enables more accurate airflow regulation and supports lower power consumption by reducing the minimum fan speed.

System integration is further simplified by the inclusion of both FG (frequency generator) and RD (rotation detection) outputs, enabling system-level monitoring without the need for device-specific variants. The MLX90411-D also supports optional pull-up or pull-down PWM inputs, eliminating the need for external inverters. This flexibility accommodates different system architectures while helping to reduce component count and overall bill of materials (BOM).

Building on the proven EMC robustness and lifetime reliability of the MLX90411 family, the MLX90411-D incorporates a comprehensive set of protection and diagnostic features. These include programmable locked-rotor protection (LRP), thermal shutdown (TSD), programmable overvoltage protection (OVP), and overcurrent protection (OCP), all contributing to safe and dependable operation under demanding conditions.

Packaged in the same SOT23-6 footprint as the MLX90411B, the MLX90411-D is fully pin-compatible, allowing customers to migrate to the new device without redesigning their hardware. Thanks to its high level of configurability, improved acoustic behavior, cost optimization, and proven reliability, the MLX90411-D is well suited for fan applications below 10 W. Typical use cases include gaming consoles, PC cooling, refrigerators, VGA/GPU cooling, as well as 24 V and 32 V industrial fans used in UPS systems, inverters, and energy storage solutions.

“MLX90411-D delivers outstanding value by combining cost efficiency with the trusted quality of Melexis, while offering enhanced flexibility,” said Xuanhong Ou, Marketing Manager at Melexis. “Its configurable speed profiles, improved acoustic performance, and simplified system integration give engineers the confidence to meet both performance and cost targets in today’s highly competitive cooling fan market.”