Startup apparatus and technique for a wireless system that uses time domain isolation
View Patent ↗A technique includes providing a butter to receive data from a processor of a wireless device in response to an active mode of the processor and selectively coupling an input terminal of a filter to the buffer based on a status of the buffer. The techniciue may be used with a wireless system that includes a digital signal processor, a buffer, a wireless interface and a switch. The buffer receives data from the digital signal processor in response to an active mode of the digital signal processor. The switch selectively couples a terminal of the wireless interface to the buffer in response to a determination of a status of the buffer.
1. A method comprising:
providing a buffer to receive data from a processor of a wireless device in response to an active mode of the processor; and
selectively coupling an input terminal of a filter to the buffer based on a status of the buffer.
2. The method of claim 1 , wherein the selectively coupling comprises isolating the input terminal of the filter from the buffer in response to the status of the buffer.
3. The method of claim 1 , wherein the filter performs digital-to-analog conversion.
4. The method of claim 1 , wherein the processor comprises a digital signal processor.
5. The method of claim 1 , further comprising:
using the digital-to-analog converter to produce an analog baseband signal received by a radio frequency receiver.
6. An apparatus comprising:
a buffer to receive data from a processor of a wireless device in response to an active mode of the processor; and
a switch to selectively couple an input terminal of an integrator to the buffer based on a status of the buffer.
7. The apparatus of claim 6 , wherein the switch isolates the input terminal of digital-to-analog converter from the buffer in response to the status of the buffer.
8. The apparatus of claim 6 , wherein the switch couples the input terminal of the integrator to a data source other than the buffer in response to the status of the buffer.
9. The apparatus of claim 6 , further comprising a switch capacitor filter that comprises a digital-to-analog converter.
10. The apparatus of claim 6 , wherein the processor comprises a digital signal processor.
11. A wireless system comprising:
a digital signal processor;
a buffer to receive data from the digital signal processor in response to an active mode of the digital signal processor;
a wireless interface having a terminal; and
a switch to selectively couple the terminal of the wireless interface to the buffer in response to a determination of a status of the buffer.
12. The wireless system of claim 11 , wherein the wireless system comprises:
a radio frequency receiver.
13. The wireless system of claim 11 , further comprising:
a modulator to modulate data provided by the processor and provide the modulated data to the buffer.
14. The wireless system of claim 13 , wherein the modulator comprises a delta sigma modulator.
15. The wireless system of claim 11 , wherein the switch isolates the input terminal of wireless interface from the buffer in response to the status of the buffer.
16. The wireless system of claim 11 , wherein the circuit couples the input terminal of the wireless interface to a data source other than the buffer in response to the status of the buffer.
17. The wireless system of claim 11 , further comprising:
a pattern generator coupled to the input terminal of the wireless interface by the circuit in response to the status of the buffer.
18. The wireless system of claim 17 , wherein the pattern generator is adapted to generate a bit stream having a zero mean.
19. The wireless system of claim 11 , wherein the wireless interface comprises a switched capacitor filter.
20. A method comprising:
providing a buffer to receive data from a processor of a wireless device in response to an active mode of the processor;
selectively coupling an input terminal of a filter to the buffer based on a status of the buffer; and
coupling the input terminal of the filter to a pattern generator in response to the status of the buffer.
21. The method of claim 20 , wherein the selectively coupling comprises isolating the input terminal of the filter from the buffer in response to the status of the buffer.
22. The method of claim 20 , wherein the selectively coupling comprises coupling the input terminal of a switched capacitor filter to a data source other than the buffer in response to the status of the buffer.
23. The method of claim 20 , further comprising:
generating a zero mean pattern using the pattern generator.
24. The method of claim 20 , wherein the filter performs digital-to-analog conversion.
25. An apparatus comprising:
a buffer to receive data from a processor of a wireless device in response to an active mode of the processor;
a switch to selectively couple an input terminal of an integrator to the buffer based on a status of the buffer; and
a pattern generator coupled to the input terminal of the integrator by the circuit in response to the status of the buffer.
26. The apparatus of claim 25 , wherein the switch isolates the input terminal of digital-to-analog converter from the buffer in response to the status of the buffer.
27. The apparatus of claim 25 , wherein the switch couples the input terminal of the integrator to a data source other than the buffer in response to the status of the buffer.
28. The apparatus of claim 25 , wherein the pattern generator is adapted to generate a zero mean data pattern.
29. The apparatus of claim 25 , further comprising a switch capacitor filter that comprises a digital-to-analog converter.
30. A method comprising:
providing a buffer to receive data from a processor of a wireless device in response to an active mode of the processor; and
selectively coupling an input terminal of a filter to the buffer based on a status of the buffer, comprising coupling the input terminal of a switched capacitor filter to a data source other than the buffer in response to the status of the buffer.