| US 7,482,959 B2 | ||
| D/A converter and communication apparatus | ||
| Akihide Sai, Kawasaki (Japan); Takeshi Ueno, Kawasaki (Japan); and Takafumi Yamaji, Yokohama (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on Dec. 27, 2005, as Appl. No. 11/319,106. | ||
| Claims priority of application No. 2004-381894 (JP), filed on Dec. 28, 2004. | ||
| Prior Publication US 2006/0139191 A1, Jun. 29, 2006 | ||
| Int. Cl. H03M 1/66 (2006.01) | ||
| U.S. Cl. 341—144 [341/135; 341/136; 341/148] | 15 Claims |
| 1. A D/A converter comprising:
a plurality of current sources configured to be on or off according to input digital data;
a constant voltage source configured to apply a constant voltage to the current sources;
current supply wirings provided between the constant voltage source and the respective current source, the current supply
wirings respectively having equal length from the constant voltage source to the respective current source;
ground-side wirings summing up output currents from the plurality of current sources; and
output terminals connected to the ground-side wirings, the output terminals outputting analogue data corresponding to the
input digital data, wherein
the current sources are constituted by transistors, and
the length of the respective current supply wiring is same as a length from the constant voltage source to a source or an
emitter of the transistor.
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