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:
Oct. 04, 2022
Filed:
Jun. 01, 2021
Sharp Display Technology Corporation, Kameyama, JP;
Adnan Heganovic, Oxford, GB;
Sharp Display Technology Corporation, Kameyama, JP;
Abstract
A pixel circuit operates to output a high drive current for high-current display applications by operating the drive transistor in the triode region. To maintain operation of the drive transistor in the triode region in a stable manner, the source-drain voltage dependence of the output current of the drive transistor is compensated with a bias transistor, which keeps the drain voltage of the drive transistor constant at a target drain voltage. The bias transistor is controlled by an operational amplifier (Opamp) running a negative feedback loop to ensure a fixed target voltage occurs at the drain of the drive transistor. To configure the negative feedback loop, the Opamp output terminal is connected to the gate of the bias transistor, with the negative terminal being connected to the drain of the drive transistor and the positive terminal being connected to a voltage supply line that supplies the target voltage.