The AMT series from Same Sky, formerly known as CUI Devices, are modular rotary encoders which offer low power consumption in motor-control applications which require accurate position sensing.
The AMT encoders are based on a capacitive sensing technology which eliminates the need for the LED light source in traditional optical encoders. This helps to reduce power usage: active current is as low as 6mA at 5V for the AMT10 and the AMT10E series. In a four-motor system, the total power consumption for the position sensing function is just 0.12W when using AMT encoders, compared to 1.7W for a typical optical encoder, and 3.2W for a magnetic encoder.
The AMT sensors consist of a fixed body and a moving element which form a variable capacitor. As the encoder rotates, an ASIC converts the changes in capacitance to position data to an accuracy of 0.2 mechanical degrees.
Unlike optical encoders, the capacitive design is resistant to interference from dust, dirt, grease and ambient light. The AMT series encoders operate reliably in the presence of strong magnetic fields which can disrupt magnetic encoders, making the AMT series more robust, and suitable for deployment in harsh environmental conditions.
The series includes variants which provide incremental, absolute, or commutation position outputs. Sleeve sizes range from 1mm to 15.875mm.
The AMT21, AMT22, and AMT24 models support an absolute position output providing the shaft position immediately at power-on, eliminating the need for a homing sequence.
