| 摘要 |
PURPOSE:To improve a linearity in the vicinity of the center of a D/A converter by providing the second D/A converter in which the output value corresponding to the M bit from the lowest order of the first D/A converter, and controlling the digital signal inputted to both D/A converters. CONSTITUTION:The first D/A converter 600 D/A-converts a digital signal of the higher order 5-bit, and the second D/A converter 700 D/A-converts a digital input signal of the lower order 3-bit, and 4-bit of the digital signal of an output terminal 520 of the digital input signal control circuit 500 equivalent to the 4-bit from the lowest order side. The control circuit 500, when the higher order 5-bit is (01111) and (10000) from the highest order side to the lowest side, fixes output terminals 515-519 to (01111), except for it, the input signal of digital signal input terminals 2-6 appears at the output terminals 515-519 as it does, and an output terminal 520 is a low level as it is. The output terminal 520 goes to be a high level when an input terminal 2 is a high level and the figures 3-6 are a low level. Namely, in the vicinity of the center, the characteristic of a good linearity of the second D/A converter is used.
|
