AS5601 achieves optimized use with rotary knobs and provides innovative push-button functions.

November 4, 2014 – ams (Country Manager Jong-Deok Lee), a specialist in high-performance analog ICs and sensors, announced the release of a highly reliable non-contact rotary position sensor (product name: AS5601) that can replace existing rotary encoders. This product is software-compatible and provides an incremental quadrature output (a method of reading the direction of rotation using phase difference) to determine whether or not it is rotating. In devices using rotary knobs, the AS5601 and its paired magnet can replace the rotary encoder without changing the host microcontroller or application software.

The AS5601 is based on ams's proven patented technology, planar magnetic Hall position sensing. This magnetic Hall position sensing technology is already widely adopted and used in the automotive, industrial, medical, and consumer markets. Because the AS5601 measures position using a non-contact rotary method, it avoids the reliability issues seen in conventional rotary encoders. Existing encoder products suffer from mechanical wear, as well as fine dust and air
Interference and premature failures due to contamination, such as dust, pollutants, and humidity, tend to occur easily.

The robust differential sensing circuit of the AS5601 also blocks interference from external magnetic stray fields.
The operation of the AS5601, including the zero position, provides easy environment configuration. This is because the product's register settings are accessed via the I2C interface and stored in the on-chip OTP memory.
Meanwhile, quadrature (A/B) output provides excellent flexibility and offers 8 to 2048 positions. This means that manufacturers of off-the-shelf rotary knobs or encoders can use the AS5601 in various end products depending on different output requirements. For designs that do not immediately replace existing rotary encoders, AS5601 users can also select a suitable 12-bit digital output.

In addition to measuring angular displacement, the AS5601 can detect button presses. The algorithm implemented in the AS5601 accurately detects a sudden decrease in the air gap between the IC and its paired magnet to generate a PUSH output signal. The push button function is not affected by changes in magnetic field strength due to temperature fluctuations or aging.
Accordingly, the AS5601 automatically adopts one of three low-power modes by default to keep power consumption at a minimum level by reducing the scanning frequency when the device is disabled at defined intervals. In the lowest power mode, the power consumption of the AS5601 is only 1.5mA.
Heinz Oyrer, Senior Global Marketing Manager overseeing ams's location sensing business unit,

“The AS5601’s outstanding signal processing circuit design can provide a simple quadrature output familiar to all rotary encoder users. In other words, this semiconductor-based rotary measurement method is the first technology capable of replacing unreliable rotary encoders in existing designs without requiring new software programming,” he said.
A demo board for the non-contact rotary position sensor AS5601 is available on the ams website. For more information on the AS5601 and to request a sample, please refer to www.ams.com/Rotary-Position-Sensor/AS5601 .