Circuit architectures and methods for A/D conversion

A method of converting an analog input voltage to a digital output, the method comprising:

• applying the analog input voltage to each of multiple transistor circuits in an array of transistor circuits, the transistor circuits having switching thresholds determined by intrinsic switching thresholds of at least one sensing transistor in a corresponding transistor circuit, the sensing transistors of all transistor circuits of a set of the transistor circuits having common physical dimensions;
• generating an encoded digital output dependent on states of the individual transistor circuits;
• sampling a signal derived from the array at a predetermined time to capture a digital sequence corresponding to a voltage applied to an input of the array of transistor circuits;
• and
• comparing the digital sequence to values stored in a look-up table to determine the voltage plied to the input of the array of transistor circuits.

A method of converting an analog input voltage to a digital output, the method comprising:

• applying the analog input voltage to each of multiple transistor circuits in an array of transistor circuits, the transistor circuits having switching thresholds determined by intrinsic switching thresholds of at least one sensing transistor in a corresponding transistor circuit, the sensing transistors of all transistor circuits of a set of the transistor circuits having common physical dimensions;
• generating an encoded digital output dependent on states of the individual transistor circuits;
• and
• storing a table of bit sequences corresponding to analog input values of the voltage source, each bit sequence including a transition zone corresponding to an input value of the voltage source.

A method of supporting analog-to-digital conversions comprising:

• generating a string of bits corresponding to an input voltage;
• identifying a contiguous bit sequence in the string of bits corresponding to a transition zone in which at least two adjacent bits are set to different logic levels;
• and
• based on a location of the contiguous bit sequence in the string of bits, storing at least a portion of the contiguous bit sequence in memory along with a corresponding digital number representing the input voltage.