US4499387A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integrated circuit formed on a semiconductor substrate with a variable capacitor circuit
Assignee: Toshiba Corp
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Filing: 1982-12-03
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Granted: 1985-02-12
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Expires: 2002-12-03
Abstract
Abstract A MOS type semiconductor integrated circuit comprising a C-MOS inverter including P- and N-channel MOS transistors connected in series between V DD and V SS power supply terminals, the gates of the MOS transistors being supplied with an input signal; a variable capacitor connected between a node at which the transistors are interconnected and a reference voltage; and a voltage generator for producing an output voltage to the variable capacitor, the voltage generator being capable of irreversibly changing the level of the output voltage, thereby changing a capacitance of the variable capacitor.
Inventors
- 👤 Satoshi Konishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:24
CPC Classifications
H; H03; H03K; H03K19/00; H03K19/003; H03K19/00369; H03K19/00384; H03K19/00346; H03K19/00361
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
144 words
An integrated circuit formed on a semiconductor substrate, comprising: a first terminal for receiving a first power supply voltage; a second terminal for receiving a second power supply voltage; a transistor circuit comprising a plurality of transistors connected in series via their drain-source current paths between said first and second terminals, at least one of the transistors being supplied with an input signal at the gate thereof; a variable capacitor circuit connected to an output terminal of said transistor circuit between a node at which two of said transistors are interconnected and a reference voltage; and a voltage generator for producing an output voltage signal applied to an input terminal of said variable capacitor circuit for controlling the capacitance thereof, the voltage generator being capable of irreversibly changing the level of the output voltage signal thereby changing the capacitance of said variable capacitor circuit.
Claim 2
Dependent Claim
144 words
An integrated circuit formed on a semiconductor substrate, comprising: a first terminal for receiving a first power supply voltage; a second terminal for receiving a second power supply voltage; a transistor circuit comprising a plurality of transistors connected in series via their drain-source current paths between said first and second terminals, at least one of the transistors being supplied with an input signal at the gate thereof; a variable capacitor circuit connected to an output terminal of said transistor circuit between a node at which two of said transistors are interconnected and a reference voltage; and a voltage generator for producing an output voltage signal applied to an input terminal of said variable capacitor circuit for controlling the capacitance thereof, the voltage generator being capable of irreversibly changing the level of the output voltage signal thereby changing the capacitance of said variable capacitor circuit.
Claim 3
Dependent Claim
14 words
An integrated circuit according to claim 1 wherein said transistors are of MOS type.
Claim 4
Dependent Claim
47 words
An integrated circuit according to claim 1 wherein said variable capacitor comprises a switching circuit applied with the output voltage signal of said voltage generator, and a capacitor circuit whose capacitance is invariable, said switching circuit and said capacitor circuit being connected in series to each other.
Claim 5
Dependent Claim
28 words
An integrated circuit according to claim 3 wherein said switching circuit comprises at least one transistor to which said output voltage signal of said voltage generator is applied.
Claim 6
Dependent Claim
26 words
An integrated circuit according to claim 4 further including a transistor connected in series to said at least one transistor and applied with another input signal.
Claim 7
Dependent Claim
25 words
An integrated circuit according to claim 3 wherein said capacitor circuit whose capacitance is invariable comprises at least one capacitor element whose capacitance is invariable.
Claim 8
Dependent Claim
31 words
An integrated circuit according to claim 3 wherein said capacitor circuit whose capacitance is invariable comprises a plurality of capacitor elements whose capacitance is invariable connected in parallel to each other.
Claim 9
Dependent Claim
38 words
An integrated circuit according to claim 3 including a further transistor connected between a node at which said switching circuit and said capacitor circuit whose capacitance is invariable are interconnected and one of said first and second terminals.
Claim 10
Dependent Claim
21 words
An integrated circuit according to claim 8 wherein said further transistor is applied with said input signal at the gate thereof.
Claim 11
Dependent Claim
33 words
An integrated circuit according to claim 8 wherein said transistor is connected at the gate to said node at which said switching circuit and said capacitor circuit whose capacitance is invariable are interconnected.
Claim 12
Dependent Claim
50 words
An integrated circuit according to claim 1 wherein said variable capacitor circuit comprises at least one MOS transistor whose drain and source node are connected to said node, whose gate is connected to the output voltage signal of said voltage generator and whose substrate is connected to said reference voltage.
Claim 13
Dependent Claim
25 words
An integrated circuit according to claim 11 wherein said reference voltage is one of said first power supply voltage and said second power supply voltage.
Claim 14
Dependent Claim
19 words
An integrated circuit according to claim 11 wherein said at least one MOS transistor is of the N-channel type.
Claim 15
Dependent Claim
19 words
An integrated circuit according to claim 11 wherein said at least one MOS transistor is of the P-channel type.
Claim 16
Dependent Claim
19 words
An integrated circuit according to claim 11 wherein said at least one MOS transistor is of the enhancement type.
Claim 17
Dependent Claim
19 words
An integrated circuit according to claim 11 wherein said at least one MOS transistor is of the depletion type.
Claim 18
Dependent Claim
77 words
An integrated circuit according to claim 1 wherein said variable capacitor circuit comprises at least one MOS capacitor comprising a semiconductor region formed in said semiconductor substrate and having a conductivity opposite to that of said semiconductor substrate, an insulation film formed on said semiconductor region and semiconductor substrate, and a gate electrode formed on said insulation film, said gate electrode being connected to said output voltage signal and said semiconductor region being connected to said node.
Claim 19
Dependent Claim
25 words
An integrated circuit according to claim 17 wherein said reference voltage is one of said first power supply voltage and said second power supply voltage.
Claim 20
Dependent Claim
17 words
An integrated circuit according to claim 17 wherein said MOS capacitor is of the N conductivity type.
Claim 21
Dependent Claim
17 words
An integrated circuit according to claim 17 wherein said MOS capacitor is of the P conductivity type.
Claim 22
Dependent Claim
16 words
An integrated circuit according to claim 17 wherein said MOS capacitor is of the enhancement type.
Claim 23
Dependent Claim
16 words
An integrated circuit according to claim 17 wherein said MOS capacitor is of the depletion type.
Claim 24
Dependent Claim
45 words
An integrated circuit according to claim 1 further comprising another transistor circuit including a plurality of transistors connected in series between said first and second terminals, said node being connected to at least one of the gates of said transistors of said another transistor circuit.
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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) | 1988-02-12 | 1988-08-13 | 1989-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-12 | 1992-08-13 | 1993-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-12 | 1996-08-13 | 1997-02-12 | $7700.00 | Window Closed / Lapsed |