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:
Jan. 24, 1989
Filed:
Mar. 14, 1988
Geoffrey W Perkins, Chandler, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A control circuit for use with personal computer monitors automatically provides single polarity horizontal and vertical sync pulses from either TTL or analog composite sync signals supplied from any of a variety of personal computers. The control circuit has both a vertical and horizontal sub-circuit each including an integrator and an exclusive OR gate wherein the inputs of the latter are coupled respectively to the input and the output of the former. Additionally the vertical sub-circuit includes a second exclusive gate the output of which is coupled to the input of the integrator thereof and whose inputs are respectively coupled to the output of the integrator of the horizontal sub-circuit and an input to which is supplied vertical TTL sync input signals while either horizontal TTL sync or TTL sync input signals are supplied to the input of the horizontal sub-circuit. In operation the control circuit defaults to the analog composite sync input in the absence of TTl horizontal or composite sync input signals. The analog composite circuit separates the horizontal and vertical sync information and applies the same to the integrator of the horizontal sub-circuit.