Audio codec adapted to dual bit-streams and methods for use therewith
View Patent ↗A audio codec includes a first analog to digital converter for producing a first one-bit data stream, a second one-bit data stream is received from a digital microphone. A selection module produces a one-bit output signal that is the first one-bit data stream when a selection signal is in a first state, and produces a the one-bit output signal that is the second one-bit data stream when the selection signal is in a second state. A decimation and filter module produces a down sampled signal based on the one-bit output signal.
1. An audio codec comprising:
a first analog to digital converter (ADC), operably coupled to a first analog input signal for producing a first one-bit data stream, the first ADC having a first plurality of ADC characteristics;
a selection module, operably coupled to the first analog to digital converter, to a second one-bit data stream from a digital microphone and a selection signal, for producing a one-bit output signal that is the first one-bit data stream when the selection signal is in a first state, and for producing the one-bit output signal that is the second one-bit data stream when the selection signal is in a second state;
a decimation and filter module, operably coupled to the one-bit output signal, for producing a down sampled signal; and
a data formatter, operably coupled to the down sampled signal, for producing a formatted digital audio signal;
wherein, the digital microphone includes a second analog to digital converter having a second plurality of ADC characteristics and wherein at least one of the first plurality of the ADC characteristics is different from a corresponding one of the second plurality of ADC characteristics.
2. The audio codec of claim 1 wherein the first plurality of the ADC characteristics includes a first ADC type and a first ADC order.
3. The audio codec of claim 1 wherein the second plurality of the ADC characteristics includes a second ADC type and a second ADC order.
4. The audio codec of claim 1 further comprising:
a controller, operably coupled to the selection module and the decimation and filter module, for producing the selection signal and for modifying at least one decimation parameter of the decimation and filter module when the selection signal is in the first state.
5. The audio codec of claim 1 further comprising:
a controller, operably coupled to the selection module and the decimation and filter module, for producing the selection signal and for modifying at least one filter parameter of the decimation and filter module when the selection signal is in the first state.
6. The audio codec of claim 1 wherein at least one of: the first analog to digital converter, the selection module, the decimation and filter module and the data formatter, are implemented on a system on a chip integrated circuit.
7. The audio codec of claim 1 wherein the down sampled signal includes a multi-bit output.
8. An audio codec comprising:
a first analog to digital converter, operably coupled to a first analog input signal for producing a first one-bit data stream;
a digital microphone interface for producing a second one-bit data stream from a digital microphone that includes a second analog to digital converter;
a selection module, operably coupled to the first analog to digital converter, to the second one-bit data stream and a selection signal, for producing a one-bit output signal that is the first one-bit data stream when the selection signal is in a first state, and for producing the one-bit output signal that is the second one-bit data stream when the selection signal is in a second state; and
a decimation and filter module, operably coupled to the one-bit output signal, for producing a down sampled signal;
wherein the second analog to digital converter (ADC) has a second ADC order and the first analog to digital converter has a first ADC order and the first ADC order is different than the second ADC order.
9. The audio codec of claim 8 wherein the second analog to digital converter (ADC) has a second ADC type and the first analog to digital converter has a first ADC type and the first ADC type is different than the second ADC type.
10. The audio codec of claim 8 wherein the second analog to digital converter includes a delta sigma modulator.
11. The audio codec of claim 8 wherein the first analog to digital converter includes a delta sigma modulator.
12. The audio codec of claim 8 further comprising:
a controller, operably coupled to the selection module and the decimation and filter module, for producing the selection signal and for modifying at least one decimation parameter of the decimation and filter module when the selection signal is in the first state.
13. The audio codec of claim 8 further comprising:
a controller, operably coupled to the selection module and the decimation and filter module, for producing the selection signal and for modifying at least one filter parameter of the decimation and filter module when the selection signal is in the first state.
14. The audio codec of claim 8 wherein at least one of: the first analog to digital converter, the digital microphone interface, the selection module, and the decimation and filter module are implemented on a system on a chip integrated circuit.
15. The audio codec of claim 8 further comprising:
a data formatter, operably coupled to the down sampled signal, for producing a formatted digital audio signal.
16. The audio codec of claim 8 wherein the down sampled signal includes a multi-bit output.
17. A method comprising:
converting a first analog input signal into a first one-bit data stream using a first analog to digital conversion method;
converting a microphone signal into a second one-bit data stream using a second analog to digital conversion method that is different from the first analog to digital conversion method;
receiving the second one-bit data stream from a digital microphone;
producing a one-bit output signal that is the first one-bit data stream when a selection signal is in a first state, and for producing the one-bit output signal that is the second one-bit data stream when the selection signal is in a second state;
decimating and filtering the one-bit output signal with a decimation and filter module to produce a down sampled signal; and
formatting the down sampled signal to produce a formatted digital audio signal.
18. The method of claim 17 further comprising:
modifying at least one decimation parameter of the decimation and filter module when the selection signal is in the first state.
19. The method of claim 17 further comprising:
modifying at least one filter parameter of the decimation and filter module when the selection signal is in the first state.
20. The method of claim 17 wherein the down sampled signal includes a multi-bit output.