Abstract: An active current steering semi-digital FIR filter for a digital-to-analog conversion circuit, which includes a shift register having a 1-bit digital input stream and a plurality of output taps, where each output tap provides a 1-bit signal which has a value of a logic 1 or a logic 0, and a plurality of current paths, where each path includes an active element, such as a transistor, having a relatively high output impedance, which is connected to a common current source, and to an op amp for current-to-voltage conversion. The relatively high output impedance of the active current steering element causes any error term resulting from offset at the op amp inputs to be minimized.
Abstract: A high swing, low power output stage for an operational amplifier is provided which includes: 1) a folded-cascode gain stage having a differential pair of natural V.sub.T devices, which are preferably P-channel transistors; 2) a source-follower input stage connected to the folded-cascode gain stage and to the input of the high swing output stage; and 3) a source-follower output stage connected to the folded-cascode gain stage connected to an output of the source-follower stage and to the output of the high swing output stage. The high swing output stage also includes a compensation capacitor which is used to provide dominant pole frequency compensation for the high swing output stage.