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US4608544A Expired / Lapsed US ⏱️ 0.0 years remaining

Oscillator circuit

Assignee: US Philips Corp
•
Filing: 1984-11-27
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Granted: 1986-08-26
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Expires: 2004-11-27
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Abstract

Abstract Oscillator circuit has a first and second transistors whose emitters are intercoupled and jointly connected to a variable current source, the first transistor being connected in a grounded-base connection. The oscillator current also has a parallel resonant circuit coupled to the collector of the first transistor, this collector being coupled for regenerative feedback of the circuit voltage to the base of the second transistor. Stabilization of the circuit voltage is accomplished by coupling the last-mentioned collector also to a control input of a variable current source, so that the collector current applied to the circuit is modulated in anti-phase with the circuit voltage, that is to say it instantaneously decreases at an increase of the circuit voltage and vice versa.

Inventors

  • 👤 Ernst H. Nordholt
  • 👤 Cornelis A. M. Boon

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 15:26
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/08; H03B5/12; H03L; H03L5/00; H03B5/1206; H03B5/1209; H03B5/1231; H03B2200/00; H03B2200/006; H03B2200/0062

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 166 words
An oscillator circuit comprising first and second transistors whose emitters are intercoupled and jointly connected to a variable current source, the first transistor being connected in a grounded-base connection, also comprising a parallel resonant circuit coupled to the collector of the first transistor, this collector being coupled to the base of the second transistor for a regenerative feedback of the circuit voltage, characterized in that said collector is also coupled to a control unit of the variable current source for an instantaneous variation of the current of the variable current source in dependence on the circuit voltage; and wherein said variable current source comprises a third transistor whose collector is connected to the intercoupled emitters of the two first and second transistors and that the collector of the first transistor is coupled via an emitter follower to a first voltage divider a first output of which is connected to the base of the second transistor and a second output to the base of the third transistor.
Claim 2
Dependent Claim 166 words
An oscillator circuit comprising first and second transistors whose emitters are intercoupled and jointly connected to a variable current source, the first transistor being connected in a grounded-base connection, also comprising a parallel resonant circuit coupled to the collector of the first transistor, this collector being coupled to the base of the second transistor for a regenerative feedback of the circuit voltage, characterized in that said collector is also coupled to a control unit of the variable current source for an instantaneous variation of the current of the variable current source in dependence on the circuit voltage; and wherein said variable current source comprises a third transistor whose collector is connected to the intercoupled emitters of the two first and second transistors and that the collector of the first transistor is coupled via an emitter follower to a first voltage divider a first output of which is connected to the base of the second transistor and a second output to the base of the third transistor.
Claim 3
Dependent Claim 51 words
An oscillator circuit as claimed in claim 1, characterized in that the current source further comprises a fourth transistor whose base is connected to a fixed base biasing voltage and whose emitter is coupled to the emitter of the third transistor, both emitters being jointly connected to a constant current source.
Claim 4
Dependent Claim 47 words
An oscillator circuit as claimed in claim 2, characterized in that a second voltage divider is arranged between a supply voltage and ground a first output thereof being coupled to the base of the first transistor and a second output to the base of the fourth transistor.

References Cited (Backward Citations)

US3665342A Cited
US3649929A Cited
DE2803430A1 Cited
JPS54148462A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-08-25 1990-02-24 1990-08-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-08-25 1994-02-24 1994-08-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-08-25 1998-02-24 1998-08-26 $7700.00 Window Closed / Lapsed

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