Claims
- 1. An integrated circuit with an oscillator, comprising:
a switching control for controlling a switching circuit, the switching control having a reference input and an output derived from a relationship of the reference input and a value of a timing element supplied to the switching control; the switching circuit operable to control circuit components to select between a plurality of operational ranges; the plurality of operational ranges being related to frequency ranges for an output of the oscillator; and the selection of operational ranges influencing the value of the timing element to modify the output of the oscillator.
- 2. The circuit according to claim 1, wherein the switching control is a comparator having a voltage reference input and an output coupled to the switching circuit.
- 3. The circuit according to claim 1, wherein the circuit components control current supplied to the timing element to select a range of operation.
- 4. The circuit according to claim 1, further comprising a reference voltage input to the switching control, the reference voltage influencing a point at which an input related to the selected operational range is applied to the timing element.
- 5. The circuit according to claim 4, wherein the timing element times at a first rate prior to application of the input and times at a second rate after application of the input.
- 6. A method for operating an oscillator, comprising:
charging a capacitor at a first rate to obtain a first time interval; charging the capacitor at a second rate to obtain a second time interval; combining the first time interval and the second time interval to obtain an oscillation frequency; and varying at least one of the first and second time intervals to change a corresponding oscillation frequency.
- 7. The method of claim 6, further comprising comparing a reference value to a charging value to influence the timing intervals.
- 8. The method according to claim 6, further comprising switching a circuit parameter to modify at least one of the first and second timing interval.
- 9. A circuit for providing a plurality of oscillator output ranges, comprising:
a timing component for providing a variable timing interval; a plurality of timing sources for influencing the timing element to vary the timing interval; a switch for switching between timing sources to vary the timing interval based on cumulative timing sources; and a switch control for controlling the switch to thereby control the timing interval based on the selected timing sources..
- 10. The circuit according to claim 9, wherein the switch control is a comparator with a reference value input.
- 11. The circuit according to claim 9, wherein the timing element is a capacitor and the timing sources are current sources that impact a charging time of the capacitor.
- 12. The circuit according to claim 11, further comprising a discharging current source for discharging the capacitor.
- 13. An circuit with an oscillator output, comprising:
an adjustable timing device for providing a first slope and a second slope forming portions of a waveform determining a period of the oscillator output; a timing device input for adjusting the timing device to selectively produce the first slope or the second slope; a timing device output indicative of a value of the waveform determined by the first slope; a reference value for comparison with the timing device output to produce a control output, the control output being operable to influence the timing device input to select the second slope.
RELATED APPLICATION
[0001] The present application is based on and claims benefit of U.S. Provisional Application No. 60/426,225, filed Nov. 14, 2002, entitled a Dual Slope Dual Range On Chip Oscillator, to which a claim of priority is hereby made.
Provisional Applications (1)
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Number |
Date |
Country |
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60426225 |
Nov 2002 |
US |