Inter-symbol interference compensation for analog-to-digital converter

A system, comprising:

• a sigma-delta analog-to-digital converter (ADC) configured to convert an analog input signal to a digital signal, wherein the digital signal is a digital approximation of the analog input signal;
• a bitstream modifier configured to:
• receive the digital signal from the sigma-delta ADC,
• output a first signal at a first output terminal, wherein the first signal is based on the digital signal, and
• output a first difference signal at a second output terminal, wherein the first difference signal includes a first difference value between a first value of the digital signal and a second value of the digital signal, wherein the second value is immediately prior to the first value in the digital signal;
• and
• an error correction system, configured to:
• receive the first signal from the first output terminal of the bitstream modifier,
• receive the first difference signal from the second output terminal of the bitstream modifier
• use the first signal and the first difference signal to determine a correction value, and
• modify the digital signal to generate a corrected digital signal by applying the correction value;
• wherein the error correction system is configured to receive a parameter value from a sensor, wherein the output of the sigma-delta ADC varies as a function of a value of the parameter and the parameter includes at least one of a semiconductor manufacturing related process variation, a voltage, and a temperature.

A system, comprising:

• a sigma-delta analog-to-digital converter (ADC) configured to convert an analog input signal to a digital signal, wherein the digital signal is a digital approximation of the analog input signal;
• a bitstream modifier, including:
• an input terminal configured to receive the digital signal from the sigma-delta ADC,
• a first signal path connected between the input terminal of the bitstream modifier and a first output terminal of the bitstream modifier to output a first signal at the first output terminal,
• a first filter between the input terminal of the bitstream modifier and the first output terminal of the bitstream modifier,
• a second signal path connected between the input terminal of the bitstream modifier and a second output terminal of the bitstream modifier, wherein the second signal path includes a first circuit configured to determine a first difference value between a first value of the digital signal and a second value of the digital signal, wherein the second value is immediately prior to the first value in the digital signal, and output the first difference value at the second output terminal as a first difference signal, and
• a second filter between the first circuit of the second signal path and the second output terminal of the bitstream modifier;
• and
• an error correction system, including:
• a first input terminal connected to the first output terminal of the bitstream modifier,
• a second input terminal connected to the second output terminal of the bitstream modifier, and
• a neural network configured to:
• use the first signal from the first output terminal and the first difference signal from the second output terminal to determine a correction value, and
• modify the digital signal to generate a corrected digital signal by applying the correction value to compensate for inter-symbol interference in the digital signal.

A method, comprising:

• receive a digital signal from a sigma-delta analog-to-digital converter (ADC);
• generating a first difference signal that includes a first difference value between a first value of the digital signal and a second value of the digital signal, wherein the second value is immediately prior to the first value in the digital signal;
• using the first signal and the first difference signal to determine a correction value;
• and
• modifying the digital signal to generate a corrected digital signal by applying the correction value to compensate for inter-symbol interference in the digital signal;
• determining a second difference value between the first value of the digital signal and the second value of the digital signal;
• determining a first squared difference value of the second difference value;
• and
• using the first squared difference signal to determine the correction value.

A method, comprising:

• receive a digital signal from a sigma-delta analog-to-digital converter (ADC);
• generating a first difference signal that includes a first difference value between a first value of the digital signal and a second value of the digital signal, wherein the second value is immediately prior to the first value in the digital signal;
• using the first signal and the first difference signal to determine a correction value;
• modifying the digital signal to generate a corrected digital signal by applying the correction value to compensate for inter-symbol interference in the digital signal;
• determining a parameter value using a sensor, wherein the parameter includes at least one of a semiconductor manufacturing related process variation, a voltage, and a temperature;
• and
• using the parameter value to determine the correction value.