Patent ID: 7109903
Filing Date: 2006-09-19
Classification: H03M

Abstract:
1. A digital-analog converter circuit for converting a digital signal of x bits, comprising: a first order unit comprising a first resister section and corresponding to a lowest-order bit or a first-order bit signal; m-th order units (m=value from 2 to x) each comprising two second resister sections series connected at a middle node and each corresponding to an m-th bit signal, wherein when the m-th order bit signal is a first level, an impedance value of the second resister section connected to a first voltage side is set to a first impedance value, and an impedance value of the second resister section connected to a second voltage side is set to a second impedance value that is twice the first impedance value, and when the m-th order bit signal is a second level, the impedance value of the second resister section connected to the first voltage side is set to the second impedance value that is twice the first impedance value, and the impedance value of the second resister section connected to the second voltage side is set to the first impedance value; and a hierarchical structure wherein an (m−1)th order unit is parallel connected to the second resister section of the m-th order unit that has been set to the second impedance value, and an x-th order unit is connected between the first reference voltage and the second reference voltage.