Digital Algorithmic Unit for Servo Control
Original Publication Date: 1984-Nov-01
Included in the Prior Art Database: 2005-Feb-05
A digital algorithmic unit, implemented on a large-scale integrated circuit chip as a number of programmed logic arrays, provides digital filtering for a number of sampled servo control loops concurrently. The digital filters have transfer functions suitable to effect the phase and amplitude compensation necessary in such servo loops and are defined by stored coefficients. The unit employs stored table multiplication techniques to calculate the filter output for a given input sample using the stored coefficients. A generalized schematic of a servo control loop is shown in Fig. 1. Typically, such loops may be employed for sampled servo head positioning or motor speed control in a disk file.