Patent US4908583A successfully refreshed from Google Patents.
US4908583A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zero phase startup for a tank type voltage controlled oscillator
Assignee: Texas Instruments Inc
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Filing: 1988-07-11
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Granted: 1990-03-13
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Expires: 2008-07-11
Abstract
Abstract A self contained circuit to enable a tank type (coil/capacitor) voltage controlled oscillator to start up and free run from a known state. The circuit allows the oscillator to be stopped to within two periods by invoking its only input logic signal and also restarted with no adverse effects on its free running operation. It includes three current mirrors, one which sets the current for the other two mirrors and of the final two, one actively sets a bias on a coil (stops oscillation) while the other makes up for the lack of coil bias by providing an equivalent amount current influx to the oscillator in the free running condition.
Inventors
- 👤 Michael H. Haight
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:47
CPC Classifications
H; H03; H03L; H03L3/00; H03B; H03B5/00; H03B5/08; H03B5/12; H03B5/1203; H03B5/1231; H03B5/1237; H03B5/124; H03B5/1246; H03B5/125
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
98 words
An oscillator system comprising: (a) a tank type oscillator having a coil and a capacitor; (b) means to control the current in said coil comprising: first means coupled to one end of said coil to provide a substantially constant normal DC current through said coil providing a substantially constant normal DC voltage at said end of said coil; second means coupled to the other end of said coil to provide a substantially constant normal DC voltage at said other end of said coil; and means responsive to a predetermined condition to reciprocatingly operate said first and second means.
Claim 2
Dependent Claim
98 words
An oscillator system comprising: (a) a tank type oscillator having a coil and a capacitor; (b) means to control the current in said coil comprising: first means coupled to one end of said coil to provide a substantially constant normal DC current through said coil providing a substantially constant normal DC voltage at said end of said coil; second means coupled to the other end of said coil to provide a substantially constant normal DC voltage at said other end of said coil; and means responsive to a predetermined condition to reciprocatingly operate said first and second means.
Claim 3
Dependent Claim
28 words
A system as set forth in claim 1 wherein said first means comprises a first current mirror circuit composed of at least a pair of NPN semiconductor devices.
Claim 4
Dependent Claim
28 words
A system as set forth in claim 1 wherein said second means comprises a second current mirror circuit composed of at least a pair of NPN semiconductor devices.
Claim 5
Dependent Claim
28 words
A system as set forth in claim 2 wherein said second means comprises a second current mirror circuit composed of at least a pair of NPN semiconductor devices.
Claim 6
Dependent Claim
21 words
A system as set forth in claim 1 further comprising means to control current flow through said first and second means.
Claim 7
Dependent Claim
36 words
A system as set forth in claim 5 wherein said means to control current flow through said first and second means comprises a current mirror circuit composed of at least a pair of PNP semiconductor devices.
Claim 8
Dependent Claim
21 words
A system as set forth in claim 2 further comprising means to control current flow through said first and second means.
Claim 9
Dependent Claim
36 words
A system as set forth in claim 7 wherein said means to control current flow through said first and second means comprises a current mirror circuit composed of at least a pair of PNP semiconductor devices.
Claim 10
Dependent Claim
21 words
A system as set forth in claim 3 further comprising means to control current flow through said first and second means.
Claim 11
Dependent Claim
36 words
A system as set forth in claim 9 wherein said means to control current flow through said first and second means comprises a current mirror circuit composed of at least a pair of PNP semiconductor devices.
Claim 12
Dependent Claim
21 words
A system as set forth in claim 4 further comprising means to control current flow through said first and second means.
Claim 13
Dependent Claim
36 words
A system as set forth in claim 11 wherein said means to control current flow through said first and second means comprises a current mirror circuit composed of at least a pair of PNP semiconductor devices.
Claim 14
Dependent Claim
27 words
A system as set forth in claim 6 wherein each of said PNP semiconductor devices is coupled to a different one of said first and second means.
Claim 15
Dependent Claim
27 words
A system as set forth in claim 8 wherein each of said PNP semiconductor devices is coupled to a different one of said first and second means.
Claim 16
Dependent Claim
27 words
A system as set forth in claim 10 wherein each of said PNP semiconductor devices is coupled to a different one of said first and second means.
Claim 17
Dependent Claim
27 words
A system as set forth in claim 12 wherein each of said PNP semiconductor devices is coupled to a different one of said first and second means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-12 | 1993-09-11 | 1994-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-12 | 1997-09-11 | 1998-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-12 | 2001-09-11 | 2002-03-13 | $7700.00 | Window Closed / Lapsed |