A new benchmark for accuracy size and cost in DC motor applications

Melexis has added the MLX92253 to its Hall-effect Dual Latch portfolio. This fast sensor provides two independent signal tracks for minimal jitter and consistent 90° phase shift regardless of magnet pole pitch. This enables accurate speed and direction ECU calculation and easy transfer across multiple platforms. This integrated solution is a cost-effective choice for DC motors and encoders in many embedded applications, including automotive, alternative mobility, consumer, and industrial.

In mobility applications, directional feedback combined with linear speed, rotational speed or angular position sensing is crucial for countless systems' fundamental operation and safety. This feedback is utilised in passenger vehicles to monitor and limit the operation of motorised systems like window lifters, seat motors, and powered tailgates. In e-bikes, it detects cadence and activates electric pedal assistance. Motor feedback also plays a crucial role in ensuring safe and precise movement in industry, our homes, and applications such as smart blinds and ventilation systems.

Engineers using a dual latch solution for stepper or DC motor applications currently rely on integrating two discrete or pitch-dependent solutions. In either case, designs are hindered by increased development, complicated and highly specific magnet designs, and increased costs. The device distinguishes itself by featuring two hall plates, one Z axis and one X axis, with two independent signal tracks. It also has a common magnetic centre, which ensures a consistent 90° phase shift (quadrature) between the two speed outputs, independent of the magnet pole pitch. Furthermore, it features a low and narrow magnetic threshold, permitting for smaller, more affordable magnets or a larger air gap to ease assembly concerns. This functionality gives engineers greater flexibility in their magnetic design and allows it to be more easily repurposed across various products.

The device offers fast and accurate feedback with low delay, low jitter, and increased reliability over conventional solutions. It features a chopping frequency of 500kHz, an operating voltage range from 2.7V to 5.5V to suit low-powered embedded designs, a wide working temperature of -40C to 150C, and output state feedback during startup. The startup feedback function can be employed to convert the two outputs into inputs during startup. This allows an MCU to retrieve the previous state of the device before power-down, ensuring that no movement is missed.

"The MLX92253 sets a new standard for affordable DC motors and encoders," said Minko Daskalov, product line manager at Melexis. "It reduces development, production, and material costs while supporting a wide range of applications that contribute to global sustainability."

The device is available now in a compact TSOT23 package. It is also available on request as engineering samples in a VA package.