Analog-to-digital converters for successive approximation incorporating delta sigma analog-to-digital converters and hybrid digital-to-analog converters with charge-sharing and charge redistribution

A method comprising:

• sampling an analog input signal to generate a plurality of bits;
• generating a first digital signal based on the analog input signal via a first analog-to-digital converter, wherein generation of the first digital signal comprises
• converting a first most-significant-bit of the plurality of bits via a charge-sharing digital-to-analog converter, and
• converting a first least significant bit of the plurality of bits via a charge redistribution digital-to-analog converter,
• wherein the first digital signal is generated based on an output of the charge-sharing digital-to-analog converter and an output of the charge redistribution digital-to-analog converter;
• generating a second digital signal based on an output of the first analog-to-digital converter via a second analog-to-digital converter including converting a second least significant bit of the plurality of bits via a delta sigma digital-to-analog converter, wherein the second digital signal is generated based on an output of the delta sigma digital-to-analog converter, and wherein the second analog-to-digital converter is a fine conversion analog-to-digital converter relative to the first analog-to-digital converter;
• and
• combining the first digital signal and the second digital signal to provide a resultant output signal.

An analog-to-digital converter comprising:

• a digital-to-analog converter circuit configured to convert a plurality of bits of a digital signal to an analog signal;
• a sample and hold circuit to sample an analog input signal;
• a subtractor configured to subtract the analog signal from an output of the sample and hold circuit;
• wherein the digital-to-analog converter circuit comprises
• a first digital-to-analog converter configured to convert a first most-significant-bit of the plurality of bits,
• a second digital-to-analog converter configured to convert a first least significant bit of the plurality of bits, and
• a third digital-to-analog converter configured to convert a second least-significant-bit of the plurality of bits;
• an amplifier configured to at least one of amplify or integrate an output of the digital-to-analog converter circuit;
• a latch configured to latch an output of the amplifier;
• and
• a successive approximation module configured to (i) receive an output of the latch, and (ii) perform successive approximations to generate the digital signal.