The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 22, 1987
Filed:
Apr. 28, 1986
Rudolph J Sterner, Cupertino, CA (US);
Steven Harris, Milpitas, CA (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
There is disclosed herein an apparatus and method for generating a first signal related to the rate of change of a second signal. In particular, a system is disclosed for generating a velocity signal in a sampled data servo system. The apparatus uses three track and hold amplifiers one of which is also a difference amplifier to sample the position error signal at selected times. A 'present' track and hold amplifier samples and holds the position error signal during the current frame. After this is done, during the same frame, a 'summing' track and hold amplifier having its difference inputs coupled to the outputs of the 'present' track and hold amplifier and to a 'previous' track and hold amplifier samples the difference between the present position error signal and the value of the position error signal during the previous sample frame. This difference divided by the sample period gives the velocity. After the difference value is sampled, the 'previous' track and hold amplifier sample is updated to the amplitude of the position error signal during the current frame in preparation for the calculation during the next frame.