Arbitrary function generator for APS injector synchrotron correction magnets

O.D. Despe
Conference Record of the 1991 IEEE Particle Accelerator Conference  
The APS injector synchrotron has eighty correction magnets around its circumference to provide the vernier field changes required for beam orbit correction during acceleration. The arbitrary function generator (AFG) design is based on scanning out encoded data from a semi-conductor memory, a first-in-first-out (FIFO) device. The data input consists of a maximum of 20 correction values specified within the acceleration window. Additional points between these values are then linearly interpolated
more » ... nearly interpolated to create a uniformly spaced 1000 data-point function stored in the FIFO. T:ach point, encoded as a 3-bit value is scanned out in synchronism with the injection pulse and used to clock the up/down counter driving the DAC. The DAC produces the analog reference voltage used to control the magnet current.
doi:10.1109/pac.1991.164669 fatcat:ffdfnsz5m5a2rcki7f6eayejra