Abstract: A feedback control-loop system that employs an active DC output control circuit is disclosed which compares an input parameter measurement against a target specification associated with the input parameter measurement. In one embodiment, the active DC output control circuit receives an input signal for laser bias adjustment. In another embodiment, the active DC output control circuit receives a motor speed input from a source, such as a tachometer, for motor speed adjustment. In another embodiment, the active DC output control circuit receives an input power amplifier measurement for wireless applications.

Abstract: Digital-to-analog converter architecture guarantees monotonicity and partial compensation for integral non-linearity. Two stages are separated by a unity-gain operational amplifier, wherein the first stage is a 1-bit resistor string-converter, having one end at reference high voltage, and the other end at reference low voltage, and the second stage is a multi-bit resistor string converter. The architecture relieves matching accuracy necessary for 1-bit front end. Resistor mismatch is compensated by varying buffer amplifier offset-voltage, and ensuring amplifier output is halfway between reference voltages; this improves integral non-linearity, or absolute accuracy, by the amount of mismatch present in the resistor string. Buffer amplifier at output of second stage of DAC controls INL error by varying offset voltage.

Abstract: The invention includes a segmented digital-to-analog converter (DAC) processing an N-bit input digital signal. A first segment converter processes the most significant bits and subsequent segment converters process the least significant bits of the N-bit input digital signal. The first segment converter includes ballast resistors that nullify the effect of any imbalance of the resistance of the first segment DAC versus the sum of the resistances in the remaining segment DACs. The first segment may be a 2, 4, 6, 8 or higher bit DAC while the second or subsequent segments may similarly be 2, 4, 6, 8, or higher bit DACs.

Abstract: The invention includes a segmented digital-to-analog converter (DAC) processing an N-bit input digital signal. A first segment converter processes the most significant bits and subsequent segment converters process the least significant bits of the N-bit input digital signal. The first segment converter includes ballast resistors that nullify the effect of any imbalance of the resistance of the first segment DAC versus the sum of the resistances in the remaining segment DACs. The first segment may be a 2, 4, 6, 8 or higher bit DAC while the second or subsequent segments may similarly be 2, 4, 6, 8, or higher bit DACs.