Analog to digital converter using folder reference circuits

An analog to digital converter comprising:

• a primary folder circuit for mapping an analog input voltage to a folder output voltage;
• a voltage reference circuit for generating a plurality of reference voltages;
• a plurality of reference folder circuits for converting a corresponding plurality of said reference voltages into a corresponding plurality of comparison voltages;
• and
• an array of comparators, each of which includes a first input terminal to which is applied said folder output voltage and a second input terminal held at one of said plurality of comparison voltages, wherein outputs of said comparators correspond to a digital representation of said analog input voltage.

An analog to digital converter comprising:

• a primary folder circuit for mapping an analog input voltage to a folder output voltage;
• a voltage reference circuit for generating a plurality of reference voltages;
• a first array of comparators, each of which includes a first input terminal to which is applied said analog input voltage and a second input terminal held at one of said reference voltages, wherein outputs of said comparators correspond to a first digital representation of said analog input voltage;
• a plurality of reference folder circuits for converting a corresponding plurality of said reference voltages into a corresponding plurality of comparison voltages;
• and
• a second array of comparators, each of which includes a first input terminal to which is applied said folder output voltage and a second input terminal held at one of said plurality of comparison voltages, wherein outputs of said comparators of said second array correspond to a second digital representation of said analog input voltage.