Next generation absolute encoders feature new magnetic sensing technique

As part of its ambitious NEXTGEN initiative, encoder-maker POSITAL has introduced a major update to its portfolio of IXARC magnetic encoders. While incremental encoders based on the new technology platform have been available for several months, the company is now rolling out a new generation of single and multiturn absolute encoders. These new encoders come with improved performance (up to 18-bit resolution), improved energy efficiency, and an optimized Wiegand package featuring a newly developed ASIC that functions as the logic controller for the battery-less multiturn system. The first absolute models released through the NEXTGEN initiative come with SSI communications interfaces. Other interfaces, including CANopen, fieldbus and industrial Ethernet will be introduced over the next few quarters.

A gamechanger for the new generation IXARC magnetic encoders is the switch from Hall-effect sensors used for rotation sensing to more advanced TMR (tunneling magneto resistance) technology. TMR offers more precise measurement of magnetic field changes, lower temperature sensitivity and lower energy consumption, with the result that TMR-equipped encoders have higher resolution and more stable performance over a wide range of operating conditions. POSITAL is among the first encoder manufacturers to use TMR technology, which has already proven itself in many automotive applications.

Another key innovation applied to the new IXARC encoders is the introduction of a new ASIC, designed in-house to support battery-free rotation counting in multiturn models. Each time the encoder shaft completes a rotation, a Wiegand sensor connected to the ASIC provides both a signal pulse and enough electrical current to energize the counter circuitry in the ASIC. With this self-powered counter system, every shaft rotation is accurately recorded in non-volatile memory – even if rotations occur when system power is not available. No backup batteries required! The new ASIC was developed jointly with POSITAL’s sister company UBITO. “Having our own ASIC is a giant step for us,” says Christian Fell, head of POSTIAL’s North American operations. “By developing our own technologies for each part of the Wiegand system, we are reducing our dependency on external suppliers and improving product availability. The more know-how and competence we build and maintain internally, the better we – the ‘Wiegand Company’ ¬– can evolve our portfolio, to the benefit of our customers.”

The new multiturn IXARC encoders also include a new generation of Wiegand sensors manufactured in a new, fully-automated production facility. This facility will have an annual capacity of over one million items. The new manufacturing system is the result of a multi-million-euro investment and offers both improved product quality and more secure supply of the vital Wiegand sensors.

The IXARC absolute encoders introduced as part of the NEXTGEN initiative are mechanically and electrically compatible with previous models.

For more information, visit www.posital.com.