Patent US4949048A successfully refreshed from Google Patents.
US4949048A
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US
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Pulse width modulation amplifier circuit
Assignee: Pioneer Corp
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Filing: 1989-11-08
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Granted: 1990-08-14
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Expires: 2009-11-08
Abstract
Abstract A pulse width modulation amplifier circuit includes a comparator which receives an analog signal and generates first and second analog signals having a phase difference of 180 degrees. A phase shifting circuit produces first and second triangular wave carrier signals so as to establish therebetween a phase difference of approximately 90 degrees. First and second pulse width modulation amplifiers, having output terminals connected to a load, pulse width modulate the first and second triangular wave carrier signals with said first and second analog signals, respectively, and amplify resultant pulse width signals.
Inventors
- 👤 Akio Tokumo
- 👤 Masayuki Kato
- 👤 Takeshi Sato
- 👤 Tatsuzo Hasegawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:48
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/20; H03F3/21; H03F3/217; H03F3/2173; H03F3/2171
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
106 words
A pulse width modulation circuit comprising: generating means receiving an analog signal, for generating first and second analog signals having phases different from each other by 180 degrees; phase shifting means for producing first and second high frequency carrier signals having phases different from each other by approximately 90 degrees; and first and second pulse width modulation amplifier means for pulse width modulating said first and second high frequency carrier signals with said first and second analog signals, respectively, and amplifying resultant pulse width signals, respectively, output terminals of said first and second pulse width modulation amplifier means being connected to opposite ends of a load.
Claim 2
Dependent Claim
106 words
A pulse width modulation circuit comprising: generating means receiving an analog signal, for generating first and second analog signals having phases different from each other by 180 degrees; phase shifting means for producing first and second high frequency carrier signals having phases different from each other by approximately 90 degrees; and first and second pulse width modulation amplifier means for pulse width modulating said first and second high frequency carrier signals with said first and second analog signals, respectively, and amplifying resultant pulse width signals, respectively, output terminals of said first and second pulse width modulation amplifier means being connected to opposite ends of a load.
Claim 3
Dependent Claim
27 words
A pulse width modulation amplifier circuit as defined in claim 1, wherein said phase values of said first and second high frequency signals differ by 90 degrees.
Claim 4
Dependent Claim
24 words
A pulse width modulation amplifier circuit as defined in claim 1, wherein said first and second high frequency carrier signals are triangular wave signals.
Claim 5
Dependent Claim
19 words
A pulse width modulation amplifier circuit as defined in claim 1, wherein said generating means comprises a differential circuit.
Claim 6
Dependent Claim
29 words
A pulse width modulation amplifier circuit as defined in claim 1, wherein each of said first and second pulse width modulation amplifier means comprises a comparator and an amplifier.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-13 | 1994-02-12 | 1994-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-13 | 1998-02-12 | 1998-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-13 | 2002-02-12 | 2002-08-14 | $7700.00 | Window Closed / Lapsed |