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. 10, 2013
Filed:
Dec. 21, 2011
Tomoyuki Iwabuchi, Kanagawa, JP;
Hiroyuki Miyake, Kanagawa, JP;
Tomoyuki Iwabuchi, Kanagawa, JP;
Hiroyuki Miyake, Kanagawa, JP;
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Abstract
Power consumption required for charging and discharging a source signal line is reduced in an active matrix EL display device. A bipolar transistor (Bi) has a base terminal B connected to an output terminal cof an operational amplifier (OP), a collector terminal C connected to a low power potential (GND), and an emitter terminal E connected to a resistor R. A high power potential (VBH) is a potential in synchronization with a high power potential of a light emitting element. A potential of the output terminal cof the operational amplifier (OP) is outputted as a buffer low power potential (VBL). The low power potential (VBL) corresponds to a potential difference between the high power potential (VBH) and a high power potential (V). Accordingly, the low power potential (VBL) can follow the high power potential (VBH), that is a high power potential of the light emitting element.