The SPiiPlus offers a powerful feature known as a Sin-Cos Encoder Multiplier. When nanometer axis position resolutions are required, users have usually been limited to expensive laser interferometer feedback systems. With the internal SPiiPlus Sin-Cos Encoder multiplier, users can use the much less expensive analog Sin-Cos encoder with 1Vptp differential outputs to achieve the required high resolution. The maximum theoretical Sin-Cos encoder multiplication factor is 65,536.
The maximum velocity is not dependant on the selected multiplication factor, and is limited to 250k sine periods per second. To achieve even higher frequencies please contact your ACS Motion Control sales representative.
The SPiiPlus PCI and linear drives were tested on a high performance XY table used for wafer inspection with Sin-Cos encoder resolutions of 4nm (250 lines per mm). Using a multiplication factor of 8,192, our engineers measured a jitter of ±2 encoder counts, which is equivalent to ~1nm. At this high resolution, the axis achieved velocities up to one meter per second.
