Delta-sigma modulator and program of delta-sigma modulator

A program for causing a computer to execute ΔΣ modulation signal processing for converting an m-value (m:

• an integer of 3 or more) digital signal into an n-value (n:
• an integer of 2 or more smaller than m) digital signal and outputting the n-value digital signal, the program causing a processor of the computer to execute:
• a step of executing signal processing in a loop filter for inputting the m-value digital signal into a subtractor;
• a step of executing n-value quantization signal processing for inputting a first output signal to be output from the loop filter and outputting a second output signal as the n-value digital signal;
• and
• a step of executing selection processing for inputting the first output signal and the second output signal, feeding back the first output signal to the subtractor of the loop filter when an absolute value of the first output signal is a predetermined value or more, and feeding back the second output signal to the subtractor of the loop filter when the absolute value of the first output signal is less than a predetermined value, wherein
• the predetermined value in the selection processing is set to be larger than a maximum value of an absolute value of a quantization value to be obtained by the n-value digital signal.

A ΔΣ modulator for converting an m-value (m:

• an integer of 3 or more) digital signal into an n-value (n:
• an integer of 2 or more smaller than m) digital signal and outputting the n-value output signal, the ΔΣ modulator comprising:
• a loop filter for inputting the m-value digital signal into a subtractor;
• a y-value quantizer for inputting a first output signal to be output from the loop filter and outputting a second output signal as a y-value (y:
• an integer of 2 or more that satisfies m≧y≧n) digital signal;
• a selecting device for inputting the first output signal and the second output signal therein, feeding back the first output signal to the subtractor of the loop filter when an absolute value of the first output signal is a predetermined value or more, and feeding back the second output signal to the subtractor of the loop filter when the absolute value of the first output signal is less than a predetermined value;
• and
• a ΔΣ modulating unit for inputting a signal fed back to the loop filter by the selection device and outputting the n-value digital signal, wherein
• the predetermined value in the selection device is set to be larger than a maximum value of an absolute value of a quantization value to be obtained by the n-value digital signal.

A program for causing a computer to execute ΔΣ modulation signal processing for converting an m-value (m:

• an integer of 3 or more) digital signal into an n-value (n:
• an integer of 2 or more smaller than m) digital signal and outputting the n-value digital signal, the program causing a processor of the computer to execute:
• a step of executing signal processing in a loop filter for inputting the m-value digital signal into a subtractor;
• a step of executing y-value quantization signal processing for inputting a first output signal to be output from the loop filter and outputting a second output signal as a y-value digital signal;
• a step of executing selection processing for inputting the first output signal and the second output signal, feeding back the first output signal to the subtractor of the loop filter when an absolute value of the first output signal is a predetermined value or more, and feeding back the second output signal to the subtractor of the loop filter when the absolute value of the first output signal is less than a predetermined value;
• and
• a step of executing ΔΣ modulation processing for inputting a signal to be fed back to the loop filter by a selecting device and outputting the n-value digital signal, wherein the predetermined value in the selection processing is set to be larger than a maximum value of an absolute value of a quantization value to be obtained by the n-value digital signal.