Data directed scrambling to improve signal-to-noise ratio
View Patent ↗Provided are methods and systems for performing binary data conversion in digital-to-analog converters (DACs) having sigma-delta modulators and involving data directed scrambling (DDS) algorithms to effectively shape the element mismatch errors to first-order shaped wideband noise. An example method may commence with receiving binary data, which comprises positive binary data and negative binary data. The method may further comprise converting, by a DDS unit, the binary data into binary thermometer code data. The conversion is performed by selectively assigning one or more logic ones in a data array from a current location of a positive (negative) pointer when positive (negative) binary data is received. A number of the one or more logic ones may be associated with the binary data. The method may further comprise circularly shifting the positive (negative) pointer to a new location within the array by the number of the one or more logic ones.
1. A method for performing binary data conversion, the method comprising:
receiving binary data, the binary data comprising positive binary data and negative binary data;
converting the binary data into binary thermometer code data by selectively assigning one or more logic ones in a data array from a current location of a positive pointer when positive binary data is received, or from a current location of a negative pointer when negative binary data is received; and
wherein a number of the one or more logic ones assigned in the data array is associated with the binary data.
2. The method of claim 1 , further comprising outputting the binary thermometer code data to a digital-to-analog converter (DAC).
3. The method of claim 2 , wherein the binary thermometer code data controls behavior of the DAC.
4. The method of claim 1 , further comprising circularly shifting the positive pointer from the current location to a new location within the data array, wherein the positive pointer is shifted by the number of the one or more logic ones.
5. The method of claim 1 , further comprising circularly shifting the negative pointer from the current location to a new location within the data array, wherein the negative pointer is shifted by the number of the one or more logic ones.
6. The method of claim 1 , wherein the data array comprises a sign bit.
7. The method of claim 6 , further comprising assigning the sign bit to zero, when positive binary data is received.
8. The method of claim 6 , further comprising assigning the sign bit to logic one, when negative binary data is received.
9. The method of claim 1 , wherein the binary data is received from a sigma-delta modulator.
10. The method of claim 1 , wherein a length of the binary thermometer code is greater than a length of the binary data per clock cycle.
11. The method of claim 10 , wherein the length of the binary thermometer code is 16-bit per clock cycle.
12. The method of claim 10 , wherein the length of the binary data is 5 bit per operating cycle.
13. The method of claim 1 , wherein the binary data represents an audio data stream.
14. A system for performing binary data conversion, the system comprising:
a receiver configured to receive binary data, the binary data comprising positive binary data and negative binary data;
a data directed scrambling unit configured to convert the binary data into binary thermometer code data by selectively assigning one or more logic ones in a data array from a current location of a positive pointer when positive binary data is received, or from a current location of a negative pointer when negative binary data is received; and
wherein a number of the one or more logic ones assigned in the data array is associated with the binary data.
15. The system of claim 14 , wherein the data directed scrambling unit includes the receiver.
16. The system of claim 14 , further comprising a digital sigma-delta modulator configured to modulate higher resolution binary data to a lower-resolution binary data to provide as the binary data to the receiver.
17. The system of claim 16 , wherein the digital sigma-delta modulator includes the receiver and the data directed scrambling unit.
18. The system of claim 14 , wherein the data directed scrambling unit is configured to circularly shift the positive pointer from the current location to a new location within the data array, wherein the positive pointer is shifted by the number of the one or more logic ones.
19. The system of claim 14 , wherein the data directed scrambling unit is further configured to circularly shift the negative pointer from the current location to a new location within the data array, wherein the negative pointer is shifted by the number of the one or more logic ones.
20. The system of claim 14 , further comprising a digital-to-analog converter (DAC).
21. The system of claim 14 , further comprising a filter, wherein the filter is configured to perform interpolation of the binary data.
22. A non-transitory processor-readable medium having embodied thereon a program being executable by at least one processor to perform a method for performing binary data conversion, the method comprising:
receiving binary data, the binary data comprising positive binary data and negative binary data;
converting the binary data into binary thermometer code data by selectively assigning one or more logic ones in a data array from a current location of a positive pointer when positive binary data is received, or from a current location of a negative pointer when negative binary data is received; and
wherein a number of the one or more logic ones assigned in the data array is associated with the binary data.