Offset error compensation of input signals in analog-to-digital converter

A method of avoiding loss of resolution in conversion of an analog input signal having an offset component to a digital signal, the method comprising:

• (a) determining a magnitude of the offset component;
• (b) producing an offset compensation control signal representative of the magnitude of the offset component;
• and
• (c) controlling a transfer of offset compensation charge into or out of a conductor in a switched capacitor input circuit of an analog-to-digital converter to adjust a signal representative of the analog input voltage being conducted by the first conductor so as to cause a conversion circuit of the analog-to-digital converter to produce a digital output signal having a full-scale value equal to the magnitude of the analog input signal plus or minus the magnitude of the offset component.

An analog-to-digital conversion system for avoiding loss of resolution in conversion of an analog input signal having an offset component to a digital signal, comprising:

• (a) means for determining a magnitude of the offset component;
• (b) means for producing an offset compensation control signal representative of the magnitude of the offset component;
• and
• (c) means for controlling a transfer of offset compensation charge into or out of a conductor in a switched capacitor input circuit of an analog-to-digital converter to adjust a signal representative of the analog input voltage being conducted by the first conductor so as to cause a conversion circuit of the analog-to-digital converter to produce a digital output signal having a full-scale value equal to the magnitude of the analog input signal plus or minus the magnitude of the offset component.