Surface-efficient reconstruction filters, especially for power-controlled D/A converters

摘要

An area-efficient low-pass, time-invariant, second-order reconstruction filter, particularly for current-driven digital-to-analog converters, comprising: a first resistor (R1) and a first capacitor (C1) which are parallel connected; an operational amplifier (3); a terminal of a second resistor (R2) which is connected to the inverting input of the operational amplifier; another terminal of the second resistor which is connected to a common node of the first resistor (R1) and the first capacitor (C1); a second capacitor (C2), which is fedback between the output of the operational amplifier and the inverting input; the filter further comprising an additional pair of resistors (R3A, R3B) which are arranged so as to be fedback between the output and the inverting input, a current signal (IDAC) arriving from a digital-to-analog converter arranged upstream of the reconstruction filter being fed to a common node of the additional pair of resistors. IMAGE