US5337020A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Differential radio frequency detector/comparator for power level control
Assignee: Matsushita Communication Industrial Corp
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Filing: 1993-03-12
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Granted: 1994-08-09
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Expires: 2013-03-12
Abstract
Abstract An automatic level control circuit for radio frequency power amplifiers which is immune to temperature and power supply induced variations. The level control circuit (42) employs a detector/comparator comprising a matched transistor pair (55) operating as a detecting differential amplifier to compare a reference signal (63) to the output power signal (83). A second amplifier (60) receives the differential output signals from the detecting amplifier and provides a power level control signal (97) to the power amplifier, thereby causing the power amplifier to produce the desired output power level.
Inventors
- 👤 Earl A. Daughtry
- 👤 Richard M. Stone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:01
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/3036; H03G3/3042; H03G1/00; H03G1/0005; H03G1/0017; H03G1/0023; H03G1/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
141 words
A circuit for providing a control signal to select the output power of a radio frequency (RF) amplifier, comprising: a first transistor having a base, an emitter, and a collector, said base being connected to a reference signal, and said collector providing a first complementary output; a second transistor having a base, an emitter, and a collector, said base being functionally connected to the output of said RF amplifier, said collector providing a second complementary output, and said emitter being connected to said emitter of said first transistor; a first resistor having a first terminal connected between said emitters of said first and second transistors and a first source of operating voltage for said transistors; and a first capacitor connected in parallel with said first resistor; whereby a predetermined one of said first and second complementary outputs provides said control signal.
Claim 2
Dependent Claim
141 words
A circuit for providing a control signal to select the output power of a radio frequency (RF) amplifier, comprising: a first transistor having a base, an emitter, and a collector, said base being connected to a reference signal, and said collector providing a first complementary output; a second transistor having a base, an emitter, and a collector, said base being functionally connected to the output of said RF amplifier, said collector providing a second complementary output, and said emitter being connected to said emitter of said first transistor; a first resistor having a first terminal connected between said emitters of said first and second transistors and a first source of operating voltage for said transistors; and a first capacitor connected in parallel with said first resistor; whereby a predetermined one of said first and second complementary outputs provides said control signal.
Claim 3
Dependent Claim
33 words
The circuit of claim 1, further comprising a differential amplifier interposed between said complementary outputs and said RF amplifier, and responsive to said first and second complementary outputs for providing said control signal.
Claim 4
Dependent Claim
13 words
The circuit of claim 2, wherein said differential amplifier comprises an operational amplifier.
Claim 5
Dependent Claim
15 words
The circuit of claim 1 wherein said first and second transistors have a common substrate.
Claim 6
Dependent Claim
44 words
The circuit of claim 1, further comprising: a second resistor connected between said collector of said first transistor and a second source of operating voltage; and a third resistor connected between said collector of said second transistor and said second source of operating voltage.
Claim 7
Dependent Claim
48 words
The circuit of claim 5, further comprising: a second capacitor connected between the collector of said first transistor and said first source of operating voltage; and a third capacitor having a first terminal connected between the collector of said second transistor and said first source of operating voltage.
Claim 8
Dependent Claim
214 words
A circuit for providing a control signal to select the output power of a radio frequency (RF) amplifier, comprising: a first transistor having a base, an emitter, and a collector, said base being connected to a reference signal and said collector providing a first complementary output; a second transistor having a base, an emitter, and a collector, said base being functionally connected to the output of said RF amplifier, said collector providing a second complementary output and said emitter being connected to said emitter of said first transistor, said first and second transistors having a common substrate; a first resistor connected between said emitters of said first and second transistors and a first source of operating voltage; a first capacitor connected in parallel with said first resistor; a second resistor connected between said collector of said first transistor and a second source of operating voltage; a third resistor connected between said collector of said second transistor and said second source of operating voltage; a second capacitor connected between said collector of said first transistor and said first source of operating voltage a third capacitor connected between said collector of said second transistor and said first source of operating voltage; and a predetermined one of said first and second complementary outputs providing said control signal.
Claim 9
Dependent Claim
214 words
A circuit for providing a control signal to select the output power of a radio frequency (RF) amplifier, comprising: a first transistor having a base, an emitter, and a collector, said base being connected to a reference signal and said collector providing a first complementary output; a second transistor having a base, an emitter, and a collector, said base being functionally connected to the output of said RF amplifier, said collector providing a second complementary output and said emitter being connected to said emitter of said first transistor, said first and second transistors having a common substrate; a first resistor connected between said emitters of said first and second transistors and a first source of operating voltage; a first capacitor connected in parallel with said first resistor; a second resistor connected between said collector of said first transistor and a second source of operating voltage; a third resistor connected between said collector of said second transistor and said second source of operating voltage; a second capacitor connected between said collector of said first transistor and said first source of operating voltage a third capacitor connected between said collector of said second transistor and said first source of operating voltage; and a predetermined one of said first and second complementary outputs providing said control signal.
Claim 10
Dependent Claim
54 words
A circuit as recited in claim 7, further comprising an amplifier having an inverting input, a noninverting input, and an output, a selected one of said inputs being connected to said first complementary output, the other one of said inputs being connected to said second complementary output, and said output providing said control signal.
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) | 1997-08-08 | 1998-02-07 | 1998-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-08 | 2002-02-07 | 2002-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-08 | 2006-02-07 | 2006-08-09 | $7700.00 | Window Closed / Lapsed |