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:
Feb. 09, 1999
Filed:
Aug. 28, 1997
Naoyuki Hamanishi, Chiba-ken, JP;
Kazuhiro Oda, Kanagawa-ken, JP;
Zdzislaw Czarnul, Kanagawa-ken, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
The present invention provides a D/A converter which has a small area in the chip, a linear current output and a high-speed operation. Each of resistors R.sub.11 -R.sub.n1 in a resistor train 11a is composed of four MOS transistors which are connected in parallel with each other and each of resistors R.sub.12 -R.sub.n2 in a resistor train 11b is composed of four MOS transistors which are connected in parallel with each other. Between the connecting nodes of the resistor trains 11a, 11b, MOS transistors ST.sub.11, ST.sub.12, ST.sub.13, ST.sub.14 -ST.sub.n1, ST.sub.n2, ST.sub.n3 and ST.sub.n4 which serve as switches and resistors are connected. All the MOS transistors have the same conductive type and size. Gate control signals C.sub.11 -C.sub.n1 ; C.sub.12 -C.sub.n2 turn MOS transistors ON but each of them has a different voltage value. A current difference between the output terminals Za and Zb is converted into a voltage difference by an operational amplifier or the like.