发明名称 Digital-to-analog converter having a ladder type resistor network.
摘要 <p>A digital-to-analog converter includes a ladder type resistor network (1) having stages equal in number to bits (d7 - d0) of a digital input signal, each of the stages including a first resistor (2) and a second resistor (3a - 3h) mutually connected in series via a node. A first switch (4 - 11), which is provided for each of the stages, selectively supplies either an upper limit voltage (AVDD) or a lower limit voltage (AVSS) to a corresponding one of the stages in accordance with a logical value of a corresponding one of the bits of the digital input signal. An analog signal output terminal (20) is coupled to the node (X) of one of the stages which corresponds to a most significant bit (d7) of the digital input signal. An analog output signal is output via the analog signal output terminal. An offset level control resistor (21) has a first end connected to the node (X, Y) of one of the stages which corresponds to a predetermined significant bit (d0) of the digital input signal and a second end. A second switch (11, 22, 23), which is coupled to the second end of the offset level control resistor (21), selectively supplies either the upper limit voltage or the lower limit voltage to the second end of the offset level control resistor.</p>
申请公布号 EP0414593(A2) 申请公布日期 1991.02.27
申请号 EP19900402302 申请日期 1990.08.16
申请人 FUJITSU LIMITED;FUJITSU VLSI LIMITED 发明人 NISHIMURA, HIROKAZU
分类号 H03M1/78 主分类号 H03M1/78
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