Digitally calibrated successive approximation register analog-to-digital converter

摘要

A circuit can include a voltage comparator Vd having a first input, a second input, and an output; a first plurality of capacitors Cp[0:n] that each have a top plate and a bottom plate, wherein each top plate is electrically coupled with the first input of the voltage comparator Vd, wherein each top plate is also switchably electrically coupled with a common mode voltage Vcm, and wherein each bottom plate is switchably electrically coupled between a first input voltage Vinp, a reference voltage Vref, the common mode voltage Vcm, and ground; a second plurality of capacitors Cn[0:n] that each have a top plate and a bottom plate, wherein each top plate is electrically coupled with the second input of the voltage comparator Vd, wherein each top plate is also switchably electrically coupled with the common mode voltage Vcm, and wherein each bottom plate is switchably electrically coupled between a second input voltage Vinn, the reference voltage Vref, the common mode voltage Vcm, and ground; and a successive approximation register (SAR) controller coupled with the output of the voltage comparator Vd.

主权项

1. A circuit, comprising:
a voltage comparator Vd having a first input, a second input, and an output; a first plurality of capacitors Cp[0:n] that each have a top plate and a bottom plate, wherein each top plate is electrically coupled with the first input of the voltage comparator Vd, wherein each top plate is also switchably electrically coupled with a common mode voltage Vcm, and wherein each bottom plate is switchably electrically coupled between a first input voltage Vinn, a reference voltage Vref, the common mode voltage Vcm, and ground; a second plurality of capacitors Cn[0:n] that each have a top plate and a bottom plate, wherein each top plate is electrically coupled with the second input of the voltage comparator Vd, wherein each top plate is also switchably electrically coupled with the common mode voltage Vcm, and wherein each bottom plate is switchably electrically coupled between a second input voltage Vinp, the reference voltage Vref, the common mode voltage Vcm, and ground; and a successive approximation register (SAR) controller coupled with the output of the voltage comparator Vd, wherein the SAR controller is configured to implement a collapsible SAR algorithm that uses balanced ternary values (−1,0,+1) for each bit to encode an analog input.