Patent US4608648A successfully refreshed from Google Patents.
Patent US5355098A successfully refreshed from Google Patents.
US5355098A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phase-locked loop with memory storing control data controlling the oscillation frequency
Assignee: Ricoh Co Ltd
•
Filing: 1993-04-22
•
Granted: 1994-10-11
•
Expires: 2013-04-22
Abstract
Abstract A phase-locked loop with memory storing control data. The control data to be given to a voltage-controlled oscillator in a phase-locked loop is addressed in accordance with an oscillation condition including the frequency of a reference signal, a dividing ratio of the frequency divider and ambient air temperature. When the phase-locked loop is controlled off, the control voltage for the voltage-controlled oscillator is changed into digital data by an analog-to-digital converter to be transferred to the memory. The digital data or control data is read out from the memory when the phase-locked loop is controlled on. The control data is then changed into analog equivalent as control voltage supplied to the voltage-controlled oscillator, shortening the locking-up time.
Inventors
- 👤 Keiichi Iwasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:59
CPC Classifications
H; H03; H03L; H03L3/00; H03L1/00; H03L1/02; H03L1/022; H03L1/026; H03L7/00; H03L7/06; H03L7/08; H03L7/10; H03L7/104; H03L7/16; H03L7/18; H03L7/183; H03L7/187; H03L7/189
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
288 words
A phase-locked loop, comprising: a voltage-controlled oscillator; a phase detector having inputs connected to an output of the voltage-controlled oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; an electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter for receiving analog signals output by said low-pass filter and for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory through which control data corresponding to said stored digital data is read out from said memory; the electronic switch connecting an output of the digital-to-analog converter to the input of the voltage-controlled oscillator when the switch is in a second position; a control unit controlling an operation of said loop; and the analog-to-digital converter comprising a reference voltage source, a comparator for comparing a plurality of individual reference voltages with the input of the voltage-controlled oscillator, an encode logic providing an appropriate digital output in accordance with an output of the comparator, and the digital-to-analog converter comprising a reference voltage source and a selector to output an individual reference voltage as analog equivalents of the control data, and the reference voltage source in the analog-to-digital converter being also used for the reference voltage source in the digital-to-analog converter.
Claim 2
Dependent Claim
288 words
A phase-locked loop, comprising: a voltage-controlled oscillator; a phase detector having inputs connected to an output of the voltage-controlled oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; an electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter for receiving analog signals output by said low-pass filter and for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory through which control data corresponding to said stored digital data is read out from said memory; the electronic switch connecting an output of the digital-to-analog converter to the input of the voltage-controlled oscillator when the switch is in a second position; a control unit controlling an operation of said loop; and the analog-to-digital converter comprising a reference voltage source, a comparator for comparing a plurality of individual reference voltages with the input of the voltage-controlled oscillator, an encode logic providing an appropriate digital output in accordance with an output of the comparator, and the digital-to-analog converter comprising a reference voltage source and a selector to output an individual reference voltage as analog equivalents of the control data, and the reference voltage source in the analog-to-digital converter being also used for the reference voltage source in the digital-to-analog converter.
Claim 3
Dependent Claim
29 words
A phase-locked loop as in claim 1, further comprising a frequency changer having an input and an output connected to the oscillator output and the phase detector input, respectively.
Claim 4
Dependent Claim
15 words
A phase-locked loop as in claim 2, wherein the frequency changer is a frequency divider.
Claim 5
Dependent Claim
15 words
A phase-locked loop as in claim 2, wherein the frequency changer is a frequency multiplier.
Claim 6
Dependent Claim
21 words
A phase-locked loop as in claim 1, wherein the reference signal is a constant frequency signal or a modulated wave signal.
Claim 7
Dependent Claim
274 words
A phase-locked loop, comprising: a voltage-controlled oscillator; a phase detector having inputs connected to an output of the voltage-controlled oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; an electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter for receiving analog signals output by said low-pass filter, and for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory through which control data corresponding to said stored digital data is read out from said memory; the electronic switch connecting an output of the digital-to-analog converter to the input of the voltage-controlled oscillator when the switch is in a second position; a control unit controlling an operation of said loop; and the analog-to-digital converter comprising a comparator comparing successively a sequence of voltages having a weighted code with the input of the voltage-controlled oscillator, a successive-approximation register having an input connected to the comparator for providing an appropriate digital output and a digital-to-analog converter for converting the digital output of the successive-approximation register into analog equivalents supplied to the comparator, and the digital-to-analog converter being also used to output analog equivalents of control data.
Claim 8
Dependent Claim
274 words
A phase-locked loop, comprising: a voltage-controlled oscillator; a phase detector having inputs connected to an output of the voltage-controlled oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; an electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter for receiving analog signals output by said low-pass filter, and for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory through which control data corresponding to said stored digital data is read out from said memory; the electronic switch connecting an output of the digital-to-analog converter to the input of the voltage-controlled oscillator when the switch is in a second position; a control unit controlling an operation of said loop; and the analog-to-digital converter comprising a comparator comparing successively a sequence of voltages having a weighted code with the input of the voltage-controlled oscillator, a successive-approximation register having an input connected to the comparator for providing an appropriate digital output and a digital-to-analog converter for converting the digital output of the successive-approximation register into analog equivalents supplied to the comparator, and the digital-to-analog converter being also used to output analog equivalents of control data.
Claim 9
Dependent Claim
29 words
A phase-locked loop as in claim 6, further comprising a frequency changer having an input and an output connected to the oscillator output and the phase detector input, respectively.
Claim 10
Dependent Claim
15 words
A phase-locked loop as in claim 7, wherein the frequency changer is a frequency divider.
Claim 11
Dependent Claim
15 words
A phase-locked loop as in claim 7, wherein the frequency changer is a frequency multiplier.
Claim 12
Dependent Claim
21 words
A phase-locked loop as in claim 6, wherein the reference signal is a constant frequency signal or a modulated wave signal.
Claim 13
Dependent Claim
247 words
A phase-locked loop, comprising: a voltage-controlled oscillator having an input for receiving a signal for varying the oscillation frequency; a phase detector having inputs connected to an output of the voltage-controlled oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; a first electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter through a second electronic switch in its first position for receiving analog signals output by said low-pass filter and for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory, through which control data corresponding to said stored digital data is read out from said memory; the first electronic switch connecting an output of the digital-to-analog converter to the input of the oscillator when the switch is in a second position; a temperature sensor having an output connected to the input of the analog-to-digital converter through the second electronic switch in its second position; and a control unit for controlling an operation of said loop.
Claim 14
Dependent Claim
247 words
A phase-locked loop, comprising: a voltage-controlled oscillator having an input for receiving a signal for varying the oscillation frequency; a phase detector having inputs connected to an output of the voltage-controlled oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; a first electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter through a second electronic switch in its first position for receiving analog signals output by said low-pass filter and for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory, through which control data corresponding to said stored digital data is read out from said memory; the first electronic switch connecting an output of the digital-to-analog converter to the input of the oscillator when the switch is in a second position; a temperature sensor having an output connected to the input of the analog-to-digital converter through the second electronic switch in its second position; and a control unit for controlling an operation of said loop.
Claim 15
Dependent Claim
29 words
A phase-locked loop as in claim 11, further comprising a frequency changer having an input and an output connected to the oscillator output and the phase detector input, respectively.
Claim 16
Dependent Claim
15 words
A phase-locked loop as in claim 12, wherein the frequency changer is a frequency divider.
Claim 17
Dependent Claim
15 words
A phase-locked loop as in claim 12, wherein the frequency changer is a frequency multiplier.
Claim 18
Dependent Claim
21 words
A phase-locked loop as in claim 11, wherein the reference signal is a constant frequency signal or a modulated wave signal.
Claim 19
Dependent Claim
259 words
A phase-locked loop, comprising: a voltage-controlled oscillator having an input for receiving a signal for varying the oscillation frequency; a phase detector having inputs connected to an output of the oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; a first electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter through a second electronic switch in its first position for receiving analog signals output by said low-pass filter for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory, through which control data corresponding to said stored digital data is read out from said memory; the first electronic switch connecting an output of the digital-to-analog converter to the input of the oscillator when the switch is in a second position; a temperature sensor having an output connected to the input of the analog-to-digital converter through the second electronic switch in its second position; a control unit controlling an operation of said loop; and at least one component of the analog-to-digital converter constitutes a component of the digital-to-analog converter.
Claim 20
Dependent Claim
259 words
A phase-locked loop, comprising: a voltage-controlled oscillator having an input for receiving a signal for varying the oscillation frequency; a phase detector having inputs connected to an output of the oscillator and an external reference signal source, respectively; a low-pass filter having an input connected to an output of the phase detector; a first electronic switch connecting an output of the low-pass filter to the oscillator input when the switch is in a first position; the voltage-controlled oscillator, the phase detector and the low-pass filter thereby forming said loop when the switch is in said first position; an analog-to-digital converter having an input connected to an output of the low-pass filter through a second electronic switch in its first position for receiving analog signals output by said low-pass filter for outputting digital signals corresponding to said received analog signals; a memory connected to an output of the analog-to-digital converter for storing digital data corresponding to said digital signals output by said analog-to-digital converter; a digital-to-analog converter, connected to the memory, through which control data corresponding to said stored digital data is read out from said memory; the first electronic switch connecting an output of the digital-to-analog converter to the input of the oscillator when the switch is in a second position; a temperature sensor having an output connected to the input of the analog-to-digital converter through the second electronic switch in its second position; a control unit controlling an operation of said loop; and at least one component of the analog-to-digital converter constitutes a component of the digital-to-analog converter.
Claim 21
Dependent Claim
29 words
A phase-locked loop as in claim 16, further comprising a frequency changer having an input and an output connected to the oscillator output and the phase detector input, respectively.
Claim 22
Dependent Claim
15 words
A phase-locked loop as in claim 17, wherein the frequency changer is a frequency divider.
Claim 23
Dependent Claim
15 words
A phase-locked loop as in claim 17, wherein the frequency changer is a frequency multiplier.
Claim 24
Dependent Claim
21 words
A phase-locked loop as in claim 16, wherein the reference signal is a constant frequency signal or a modulated wave signal.
Claim 25
Dependent Claim
90 words
A phase-locked loop as in any one of claims 16-20, wherein the analog-to-digital converter comprises a reference voltage source, a comparator to compare the individual reference voltage with the input signal, an encode logic providing an appropriate digital output in accordance with the comparator output, the digital-to-analog converter comprises a reference voltage source and a selector to output an individual reference voltage as analog equivalents of the control data, and the reference voltage source in the analog-to-digital converter is also used for the reference voltage source in the digital-to-analog converter.
Claim 26
Dependent Claim
83 words
A phase-locked loop as in any one of claims 16-20, wherein the analog-to-digital converter comprises a comparator comparing successively a sequence of voltages having a weighted code with the input of the voltage-controlled oscillator, a successive-approximation register having an input connected to the comparator providing an appropriate digital output and a digital-to-analog converter to convert the digital output of the successive-approximation register into analog equivalents supplied to the comparator, and the digital-to-analog converter is also used to output analog equivalents of control data.
References Cited (Backward Citations)
US4906944A
Cited
US4980652A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-10-10 | 1998-04-11 | 1998-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-10 | 2002-04-11 | 2002-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-10-10 | 2006-04-11 | 2006-10-11 | $7700.00 | Window Closed / Lapsed |