| 摘要 |
A digital-to-analog converter includes an input circuit (9) producing a plurality of corresponding switch control signals (25) in response to a digital input signal (DIN) and a resistive ladder network (10A) including an R/2R MSB ladder section (2) including a plurality of "R" resistors (17) and a plurality of "2R" resistors (5), and an R/2R LSB ladder section (3) including a plurality of "R" resistors (17) and a plurality of "2R" resistors (5). A scaling resistor (21) is coupled between a least significant node conductor (7-3) of the MSB ladder section and a most significant node conductor (7-4) of the LSB ladder section. A plurality of switch circuits (6) each selectively conducts a respective parallel resistor circuit (5) to a first reference voltage conductor (VREFH) or a second reference voltage conductor (VREFL) in response to the various switch control signals (25). The resistances of the resistors of the "R" resistors of the MSB ladder section are different than the resistances of the resistors of the "R" resistors of the LSB ladder section. The resistances of the "R" resistors of the MSB ladder section, the resistances of the "R" resistors of the LSB ladder section, and the resistance of the scaling resistor are related by the expression R''=2R-R', where R'' is the resistance of a scaling resistor, R is the resistance of the "R" resistors of the MSB ladder section, and R' is the resistance of the "R" resistors of the LSB ladder section.
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