DIGITAL-TO-ANALOG CONVERTER

摘要

PURPOSE:To set a coupling capacitor to a unit capacitance value, by cascade- connecting the 1st and 2nd same capacitor trains weighted in binary with the smallest capacitor in the capacitor trains. CONSTITUTION:A digital input of high-order digit is applied to an input terminal 1 of the 1st capacitor train M-DAC weighted in binary, and the digital input of low-order digit is given to the input terminal 1 of the 2nd capacitor train L- DAC. The M-DAC and L-DAC are coupled via a coupling capacitor 5 and a buffer amplifier 6 is connected to the M-DAC to pick up an output. The digital input controls a switch 3 and obtains an analog value corresponding to the digital input. The capacitance value of the coupling capacitor 5 is minimum among the capacitor trains M-DAC and L-DAC.