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:
Nov. 09, 2021
Filed:
Nov. 27, 2018
Planar Systems, Inc., Beaverton, OR (US);
Shahnad Nadershahi, Beaverton, OR (US);
Planar Systems, Inc., Beaverton, OR (US);
Abstract
Active discharge circuitry for fast discharging of charge on an LED display matrix includes a mechanism to effectuate circuit path switching so as to electrically connect a charged node to a discharge circuit for controlled discharging of unwanted charge until it reaches a desired (e.g., programmable) value. The active discharge circuitry includes a control circuit generating appropriate timing and digital control signals for starting and stopping (e.g., actuating a switch) the discharge activities. The disclosed techniques accommodate variations in channel-to-channel start times for mitigating ghosting effects that would otherwise be presented from the LED display matrix due to residual (i.e., unwanted) charges remaining electrically loaded on display elements via, for example, charged parasitic capacitance or other such transients, after a current driver of a specific channel has stopped driving.