High-Resolution 12-Bit Segmented Capacitor DAC in Successive Approximation ADC

This paper study the segmented split capacitor Digital-to-Analog Converter (DAC) implemented in a differentialtype 12-bit Successive Approximation Analog-to-Digital Converter (SA-ADC). The series capacitance split array method employed as it reduced the total area of the capacitors required for high resolution DACs. A 12-bit regular binary array structure requires 2049 unit capacitors (Cs) while the split array needs 127 unit Cs. These results in the reduction of the total capacitance and power consumption of the series split array architectures as to regular binary-weighted structures. The paper will show the 12-bit DAC series split capacitor with 4-bit thermometer coded DAC architectures as well as the simulation and measured results.

Authors:

• Wee Leong Son
• Hasmayadi Abdul Majid
• Rohana Musa

Keywords:

• Successive Approximation Register Analog-to- Digital Converter
• SAR ADC
• Low voltage ADC.

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