| CPC H03M 1/145 (2013.01) [H03M 1/0612 (2013.01); H03M 1/164 (2013.01)] | 20 Claims |

|
1. An analog-to-digital converter (ADC), comprising:
an input terminal configured to receive an analog input voltage;
a current mode digital-to-analog converter (DAC) stage including
a transconductance amplifier (Gm) connected to the input terminal, the transconductance amplifier having a first plurality of transconductance amplifier cells, the transconductance amplifier configured to sample the analog input voltage in response to a first phase clock signal and convert the analog input voltage to a first current signal,
a current mode DAC having a second plurality of current mode DAC unit cells and configured to convert a first digital value corresponding to the analog input voltage to a second current signal,
the current mode DAC stage configured to determine a residue current signal representing a difference between the first current signal and the second current signal, and convert the residue current signal to an analog residual voltage signal;
a residue amplifier configured to convert the residue current signal to analog residue voltage signal, the residue amplifier including first and second stages, the first stage having a wideband self-biased amplifier and the second stage including a common mode feedback circuit;
an alignment and digital error correction stage configured to combine the first digital value and a second digital value representing the analog residue voltage signal into a digital output voltage; and
an output terminal coupled to the alignment and error correction stage configured to output the digital output voltage.
|