Silicon Laboratories Inc.
Resistor based delta sigma multiplying DAC with integrated reconstruction filter

Abstract:

A digital to analog converter that includes a delta sigma modulator coupled to receive a digital data. The delta sigma modulator supplies a multi-bit resistor digital to analog converter (DAC). The multi-bit resistor digital to analog converter supplies an amplifier with an analog signal corresponding to the digital data. A first low pass filter is coupled between the multi-bit digital to analog converter and the amplifier stage and filters out shaped quantization noise before it reaches the amplifier. A second low pass filter is coupled to an output of the amplifier stage and filters out residual quantization noise and chopping artifacts from the amplifier stage.