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:
Apr. 15, 2003
Filed:
Sep. 22, 1999
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A D/A conversion circuit which can perform D/A conversion at high speed and with high precision is disclosed. The D/A conversion circuit comprises an analog reference power supply, an output buffer, a multiplexer, a pre-buffer, and a current changeover switch. The pre-buffer operates with a power supply voltage different from that of the analog reference power supply, and outputs a voltage substantially equal to an output voltage of the analog reference power supply. For a predetermined period after logic of digital data changes, the output voltage of the pre-buffer is supplied to the output buffer, and an input parasitic capacitor of the output buffer is charged/discharged. After the predetermined period elapses, the output voltage of the analog reference power supply is supplied to the output buffer. Therefore, a charging/discharging current of the input parasitic capacitor does not flow through the analog reference power supply, and fluctuation of the output voltage of the analog reference power supply can be suppressed.