Automatic frequency calibration
First Claim
1. A method for providing an oscillating signal, comprising:
- generating a reference signal;
generating an oscillating signal whose frequency is based on the reference signal;
sending the oscillating signal to a frequency sensitive element;
producing an output signal from the frequency sensitive element, said output signal depending on the frequency of the oscillating signal, wherein the output signal does not depend on a crystal oscillator; and
controlling the frequency of the oscillating signal by modifying an attribute of the reference signal until an attribute of the output signal of the frequency sensing element falls within a desired range of values.
2 Assignments
0 Petitions
Accused Products
Abstract
Disclosed is a system and method for providing an oscillating signal of relatively precise frequency without using a signal provided by a crystal as a reference. Disclosed is a feedback oscillator circuit configured to output an oscillating signal having a frequency defined by a reference signal. The oscillating signal can be sent to one or more circuits including at least one frequency sensitive element. The frequency sensitive element produces an output signal which depends on the frequency of the oscillating signal. A controller controls the reference signal in order to cause an attribute of the output signal to have a value within a desired range.
93 Citations
35 Claims
-
1. A method for providing an oscillating signal, comprising:
-
generating a reference signal; generating an oscillating signal whose frequency is based on the reference signal; sending the oscillating signal to a frequency sensitive element; producing an output signal from the frequency sensitive element, said output signal depending on the frequency of the oscillating signal, wherein the output signal does not depend on a crystal oscillator; and controlling the frequency of the oscillating signal by modifying an attribute of the reference signal until an attribute of the output signal of the frequency sensing element falls within a desired range of values. - View Dependent Claims (5, 6, 7, 8, 9, 10, 11, 12)
-
- 2. The method of claim 2, wherein the frequency sensitive element is a band pass filter and the attribute of the output signal of the frequency sensitive element is the voltage of said output signal.
-
13. A method for tuning the frequency of an oscillating signal comprising:
-
scanning a reference signal by periodically changing the reference signal so that a plurality of different versions of the reference signal within a scanning range are generated; generating an oscillating signal, the frequency of the oscillating signal being based on the reference signal; sending the oscillating signal to a frequency sensitive element; monitoring an output of the frequency sensitive element for each different version of the reference signal. wherein the output of the frequency sensitive element does not depend on a crystal oscillator; selecting a desirable version of the reference signal based on the monitored output of the frequency sensitive element; setting the reference signal at the desirable version of the reference signal. - View Dependent Claims (14, 15, 16)
-
-
17. An electronic device comprising:
-
a feedback oscillator circuit configured to generate an oscillating signal whose frequency is based on an incoming reference signal; a reference signal generator configured to generate the reference signal based on a control signal; and a frequency sensitive element, configured to receive the oscillating signal and generate an output signal based on the frequency of the oscillating signal, and not based on a crystal oscillator; a controller configured to receive the output signal, and modify the value of the control signal based on the value of the output signal in order to bring the output signal into a range of predetermined desired values. - View Dependent Claims (18, 19, 20, 21, 22)
-
-
23. A circuit for generating an oscillating signal comprising:
-
a feedback oscillator circuit configured to generate an oscillating signal whose frequency is based on an incoming reference signal and send the oscillating signal to a frequency sensitive element, configured to receive the oscillating signal and generate an output signal based on the frequency of the oscillating signal and not based on a crystal oscillator; a reference signal generator configured to generate the reference signal based on a control signal; a controller configured to receive the output signal, and modify the value of the control signal based on the value of the output signal in order to bring the output signal into a range of predetermined desired values. - View Dependent Claims (24)
-
-
25. An electronic device comprising:
-
a touch sensitive panel configured to receive an oscillating signal and generate an output signal based on the received oscillating signal and is not based on a crystal oscillator; an oscillating circuit configured to generate the oscillating signal; and a controller configured to control the frequency of the oscillating signal by controlling the oscillating circuit, wherein the controller is further configured to receive the output signal, and control the frequency of the oscillating signal so that a desired value of an attribute of the output signal is achieved. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32, 33)
-
-
34. A mobile telephone comprising:
-
a feedback oscillator circuit configured to generate an oscillating signal whose frequency is based on an incoming reference signal and is not based on a crystal oscillator; a reference signal generator configured to generate the reference signal based on a control signal; and a frequency sensitive element, configured to receive the oscillating signal and generate an output signal based on the frequency of the oscillating signal; a controller configured to receive the output signal, and modify the value of the control signal based on the value of the output signal in order to bring the output signal into a range of predetermined desired values.
-
-
35. A portable audio player comprising:
-
a feedback oscillator circuit configured to generate an oscillating signal whose frequency is based on an incoming reference signal and is not based on a crystal oscillator; a reference signal generator configured to generate the reference signal based on a control signal; and a frequency sensitive element, configured to receive the oscillating signal and generate an output signal based on the frequency of the oscillating signal; a controller configured to receive the output signal, and modify the value of the control signal based on the value of the output signal in order to bring the output signal into a range of predetermined desired values.
-
Specification