Method and system for using a frequency locked loop logen in oscillator systems

• US 7,586,378 B2
• Filed: 07/31/2007
• Issued: 09/08/2009
• Est. Priority Date: 03/19/2007
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Wu, Stephen, Welz, Jared, Ibrahim, Brima Babatunde
• Primary Examiner(s): MIS, DAVID C
• Application Number:
  US11/831,399
• Publication Number:
  US 20080231375A1
• Time in Patent Office: 770 Days
• Field of Search: 331/1.A, 331/14, 331/17, 331/18, 331/25, 331/DIG.2, 327156-159, 332/127, 360/51, 375/376, 455/260
• US Class Current: 331/14
• CPC Class Codes: H03L 7/085 concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal H03L7/10 takes precedence; circuits for comparing the phase or frequency of two mutually-independent oscillations H03D13/00
• CPC Class Codes: H03L 7/181 a numerical count result being used for locking the loop, the counter counting during fixed time intervals H03L7/1806 takes precedence

Abstract

Aspects of a method and system for using a frequency locked loop LOGEN in oscillator systems may include generating an oscillating signal via one or more circuits comprising a feedback loop. The generation may be controlled by enabling or disabling the feedback loop, based on the generated oscillating signal. The one or more circuits may comprise a frequency-locked loop (FLL) that may enable the generation of the oscillating signal. The frequency-locked loop may comprise a voltage-controlled oscillator. The feedback loop may be disabled when an estimated frequency difference between a reference signal and a feedback signal may be less than or equal to a specified threshold. The feedback loop may be enabled when an estimated frequency difference between a reference signal and a feedback signal may be greater than a particular threshold.

Claims

1. A method for processing signals, the method comprising:

generating an oscillating signal via one or more circuits comprising a feedback loop; and

controlling said generation by enabling or disabling said feedback loop utilizing a digital-to-analog converter, based on a comparison of said generated oscillating signal and an input signal, wherein said digital-to-analog converter is triggered by said input signal and an output of said digital-to-analog converter adjusts said oscillating signal when said feedback loop is enabled, and an output of said digital-to-analog converter remains constant when said feedback loop is disabled.

2. The method according to claim 1, wherein said one or more circuits comprise a frequency-locked loop (FLL) that enables said generation of said oscillating signal.

3. The method according to claim 2, wherein said frequency-locked loop comprises a voltage-controlled oscillator.

4. The method according to claim 1, comprising disabling said feedback loop when an estimated frequency difference between a reference signal and a feedback signal is less than or equal to a specified threshold.

5. The method according to claim 1, comprising enabling said feedback loop when an estimated frequency difference between a reference signal and a feedback signal is greater than a particular threshold.

6. The method according to claim 1, wherein said one or more circuits comprise a non-return-to-zero digital-to-analog converter and one or more inputs of said non-return-to-zero digital-to-analog converter are activated for said controlling said generation of said oscillating signal.

7. The method according to claim 1, wherein said one or more inputs of said digital-to-analog converter are deactivated for said constant output of said digital-to-analog converter.

8. The method according to claim 1, wherein said one or more circuits comprise a transmitter.

9. The method according to claim 8, wherein said transmitter comprises an FM radio transmitter.

10. The method according to claim 1, wherein said one or more circuits comprises a receiver.

11. The method according to claim 10, wherein said receiver comprises an FM radio receiver.

12. The method according to claim 1, comprising modulating a radio-frequency signal using said generated oscillating signal.

13. The method according to claim 1, comprising demodulating a radio-frequency signal using said generated oscillating signal.

14. A system for processing signals, the system comprising:

one or more circuits comprising a feedback loop and digital-to-analog converter, said one or more circuits enable;

generation of an oscillating signal; and

control of said generation by enabling or disabling said feedback loop utilizing a digital-to-analog converter, based on a comparison of said generated oscillating signal and an input signal, wherein said digital-to-analog converter is triggered by said input signal and an output of digital-to-analog converter adjusts said oscillating signal when said feedback loop is enabled and an output of said digital-to-analog converter remains constant when said feedback loop is disabled.

15. The system according to claim 14, wherein said one or more circuits comprise a frequency-locked loop (FLL) that enables said generation of said oscillating signal.

16. The system according to claim 15, wherein said frequency-locked loop comprises a voltage-controlled oscillator.

17. The system according to claim 14, wherein said one or more circuits disable said feedback loop when an estimated frequency difference between a reference signal and a feedback signal is less than or equal to a specified threshold.

18. The system according to claim 14, wherein said one or more circuits enable said feedback loop when an estimated frequency difference between a reference signal and a feedback signal is greater than a particular threshold.

19. The system according to claim 14, wherein said one or more circuits comprise a non-return-to-zero digital-to-analog converter and one or more inputs of said non-return-to-zero digital-to-analog converter are activated for said control of said generation of said oscillating signal.

20. The system according to claim 14, wherein said one or more inputs of said digital-to-analog converter are deactivated for said disabling of said constant output of said digital-to-analog converter.

21. The system according to claim 14, wherein said one or more circuits comprise a transmitter.

22. The system according to claim 21, wherein said transmitter comprises an FM radio transmitter.

23. The system according to claim 14, wherein said one or more circuits comprises a receiver.

24. The system according to claim 23, wherein said receiver comprises an FM radio receiver.

25. The system according to claim 14, wherein said one or more circuits modulate a radio-frequency signal using said generated oscillating signal.

26. The system according to claim 14, wherein said one or more circuits demodulate a radio-frequency signal using said generated oscillating signal.