US3742249A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit for phase comparison
Assignee: TDK Micronas GmbH
•
Filing: 1971-03-10
•
Granted: 1973-06-26
•
Expires: 1991-03-10
Abstract
Abstract An apparatus and method for phase comparison wherein a local oscillator generates a delta voltage containing a D.C. component. The delta voltage is compared with a threshold voltage derived from the delta voltage, resulting in a control signal the polarity of which depends on the outcome of the comparison. This control signal sets the frequency of the local oscillator.
Inventors
- 👤 A Gerlach
- 👤 R Burth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:10
CPC Classifications
H; H03; H03D; H03D13/00; H03D13/005; H04; H04N; H04N5/00; H04N5/04; H04N5/06; H04N5/067; H04N5/073
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
136 words
A phaSe comparator circuit for synchronizing two pulse sequences, comprising: a first means for receiving a first sequence of pulses; a source of supply voltage; means for deriving a voltage threshold level from said supply voltage; a differential amplifier having a first input coupled to a delta voltage and a second input coupled to said threshold voltage; first and second series connected constant current sources coupled to the output of said differential amplifier; a transistor coupled to the common-emitter circuit of said differential amplifier, the base of said transistor controlled by said first sequence of pulses; and means for generating a control signal of one polarity when the momentary value of said delta voltage is higher than said voltage threshold level, and of an opposite polarity when said momentary value is less than said threshold level.
Claim 2
Dependent Claim
136 words
A phaSe comparator circuit for synchronizing two pulse sequences, comprising: a first means for receiving a first sequence of pulses; a source of supply voltage; means for deriving a voltage threshold level from said supply voltage; a differential amplifier having a first input coupled to a delta voltage and a second input coupled to said threshold voltage; first and second series connected constant current sources coupled to the output of said differential amplifier; a transistor coupled to the common-emitter circuit of said differential amplifier, the base of said transistor controlled by said first sequence of pulses; and means for generating a control signal of one polarity when the momentary value of said delta voltage is higher than said voltage threshold level, and of an opposite polarity when said momentary value is less than said threshold level.
Claim 3
Dependent Claim
38 words
A phase comparator circuit according to claim 1 further including a filter circuit coupled to said two constant current sources, said filter circuit having a time constant capable of being adjusted in dependence upon the degree of synchronization.
Claim 4
Dependent Claim
21 words
A phase comparator circuit according to claim 1 further including a phase inverter preceeding said two series connected constant current sources.
Claim 5
Dependent Claim
23 words
A phase comparator circuit according to claim 1 wherein each of said constant current sources includes one transistor arranged complementary to the other.
References Cited (Backward Citations)
US2927279A
Cited
US3073972A
Cited
US3241078A
Cited
US3315089A
Cited
US3309618A
Cited
US3475622A
Cited
US3337814A
Cited
US3512096A
Cited
US3597631A
Cited
US3610955A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |