US3886458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency converter circuit with integrated injection capacitor
Assignee: Sony Corp
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Filing: 1973-12-06
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Granted: 1975-05-27
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Expires: 1993-12-06
Abstract
Abstract In a signal converter circuit having a mixer circuit with an input terminal for receiving radio frequency (RF) signals and locally oscillated signals, by way of an injection or coupling capacitor, from the output of a local oscillator circuit, such injection or coupling capacitor is formed between a pair of terminals of a capacitor element provided on a semiconductor substrate on which at least portions of the mixer and local oscillator circuits are also formed, and the capacitor element is connected with the mixer and local oscillator circuits so that the stray capacitor appearing between one of the capacitor element terminals and the substrate is at the mixer circuit side of injection capacitor rather than at the local oscillator side of the latter.
Inventors
- 👤 Shigeo Matsumoto
- 👤 Yukio Tsuda
- 👤 Tadaharu Tsuyuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:29
CPC Classifications
H; H03; H03D; H03D7/00; H03D7/12; H10; H10D; H10D1/00; H10D1/60; H10D1/62; H10D84/00; H10D84/60; H10D84/611; H10D84/613; H10D84/615
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
141 words
A signal converter circuit comprising a mixer circuit having input and output terminals, means for supplying input signals to be converted to said input terminal of the mixer circuit, a local oscillator circuit having an output terminal, a capacitor element formed on a semiconductor substrate and having first and second terminals, said capacitor element providing a main capacitor between said first and second terminals and a stray capacitor between said first terminal and said semiconductor substrate, and means connecting said first and second terminals of the capacitor element to said input terminal of the mixer circuit and to said output terminal of the local oscillator circuit, respectively, so that said main capacitor functions as an injection capacitor for the output of said local oscillator circuit with said stray capacitor being at the side of said injection capacitor toward said mixer circuit.
Claim 2
Dependent Claim
141 words
A signal converter circuit comprising a mixer circuit having input and output terminals, means for supplying input signals to be converted to said input terminal of the mixer circuit, a local oscillator circuit having an output terminal, a capacitor element formed on a semiconductor substrate and having first and second terminals, said capacitor element providing a main capacitor between said first and second terminals and a stray capacitor between said first terminal and said semiconductor substrate, and means connecting said first and second terminals of the capacitor element to said input terminal of the mixer circuit and to said output terminal of the local oscillator circuit, respectively, so that said main capacitor functions as an injection capacitor for the output of said local oscillator circuit with said stray capacitor being at the side of said injection capacitor toward said mixer circuit.
Claim 3
Dependent Claim
35 words
A signal converter circuit according to claim 1, wherein at least a portion of said mixer circuit and a portion of said local oscillator circuit are formed on said semiconductor substrate with said capacitor element.
Claim 4
Dependent Claim
17 words
A signal converter circuit according to claim 2, wherein said capacitor element is of the MOS type.
Claim 5
Dependent Claim
18 words
A signal converter circuit according to claim 2, wherein said capacitor element is of the PN junction type.
Claim 6
Dependent Claim
38 words
A signal converter circuit according to claim 1, wherein said means for supplying input signals to said input terminal of the mixer circuit includes a resonant circuit having at least one capacitor in parallel with said stray capacitor.
References Cited (Backward Citations)
US3641441A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |