Hybrid switching scheme for a capacitor digital-to-analog circuit in a successive approximation register analog-to-digital converter

An apparatus, comprising:

• means for coupling a first terminal of a first capacitor in a first capacitive digital-to-analog converter (DAC) to one of three voltages based on a value of a first ternary number;
• means for coupling a first terminal of a second capacitor in the first capacitive DAC to one of the three voltages selected by a value of a first single-digit binary number;
• means for coupling a first terminal of a first capacitor in a second capacitive DAC to one of the three voltages based on a value of a second ternary number;
• and
• means for coupling a first terminal of a second capacitor in the second capacitive DAC to one of the three voltages selected by a value of a second single-digit binary number.

A method for performing analog-to-digital conversion, comprising:

• coupling a first terminal of a first capacitor in a first capacitive digital-to-analog converter (DAC) to one of three voltages based on value of a first ternary number;
• coupling a first terminal of a second capacitor in the first capacitive DAC to one of two voltages based on value of a first single-digit binary number;
• coupling a first terminal of a first capacitor in a second capacitive DAC to one of the three voltages based on value of a second ternary number;
• and
• coupling a first terminal of a second capacitor in the second capacitive DAC to one of two voltages based on value of a second single-digit binary number.