US5025230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oscillator circuit incorporated in a semiconductor circuit
Assignee: Toshiba Corp
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Filing: 1990-05-16
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Granted: 1991-06-18
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Expires: 2010-05-16
Abstract
Abstract An oscillator circuit incorporated in a semiconductor integrated circuit and comprising an oscillation input terminal, an oscillator output terminal, an inverting logic circuit, and a transmission gate. The terminals and are connected to an external oscillator. The inverting logic circuit comprises an N-type MOS transistor and a P-type MOS transistor. The input and output terminals of the logic circuit are connected to the oscilllation input and output terminals, respectively. The transmission gate comprises an N-type MOS transistor and a P-type MOS transistor. Either MOS transistors has a source electrode and a drain electrode, one of which is connected to said oscillation input terminal, and the other of which is said oscillation output terminal. The gate-insulating film at least one of said MOS transistors incorporatedin the transmission gate is thicker than those of other MOS transistors formed on the semiconductor substrate.
Inventors
- 👤 Hitoshi Kondo
- 👤 Hiroyuki Suwabe
- 👤 Aiki Kojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:11
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/30; H03B5/32; H03B5/36; H03B5/364; H03K; H03K3/00; H03K3/02; H03K3/027; H03K3/03; H03K3/0307; H10; H10D; H10D84/00; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10D84/8314
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
217 words
An oscillator circuit incorporated in a semiconductor integrated circuit and having an oscillation input terminal and an oscillator output terminal to which an external oscillator is connected, said oscillator circuit comprising: an inverting logic circuit comprising transistors formed on the semiconductor substrate of said semiconductor integrated circuit, connected to receive a signal input through said oscillation input terminal, and adapted to supply an output signal through said oscillation output terminal; an N-type MOS transistor formed on said semiconductor substrate, and having a source electrode and a drain electrode one of which is connected to said oscillation input terminal, and the other of which is connected to said oscillation output terminal, and a gate electrode which is connected to receive a first potential for turning on the N-type MOS transistor; and a P-type MOS transistor formed on said semiconductor substrate, and having a gate-insulating film, a source electrode and a drain electrode, one of which is connected to said oscillation input terminal, and the other of which is connected to said oscillation output terminal, and a gate electrode which is connected to receive a second potential for turning on the P-type MOS transistor, wherein the gate-insulating film of at least one of said MOS transistors is thicker than those of other MOS transistors formed on said semiconductor substrate.
Claim 2
Dependent Claim
217 words
An oscillator circuit incorporated in a semiconductor integrated circuit and having an oscillation input terminal and an oscillator output terminal to which an external oscillator is connected, said oscillator circuit comprising: an inverting logic circuit comprising transistors formed on the semiconductor substrate of said semiconductor integrated circuit, connected to receive a signal input through said oscillation input terminal, and adapted to supply an output signal through said oscillation output terminal; an N-type MOS transistor formed on said semiconductor substrate, and having a source electrode and a drain electrode one of which is connected to said oscillation input terminal, and the other of which is connected to said oscillation output terminal, and a gate electrode which is connected to receive a first potential for turning on the N-type MOS transistor; and a P-type MOS transistor formed on said semiconductor substrate, and having a gate-insulating film, a source electrode and a drain electrode, one of which is connected to said oscillation input terminal, and the other of which is connected to said oscillation output terminal, and a gate electrode which is connected to receive a second potential for turning on the P-type MOS transistor, wherein the gate-insulating film of at least one of said MOS transistors is thicker than those of other MOS transistors formed on said semiconductor substrate.
Claim 3
Dependent Claim
63 words
The oscillator circuit according to claim 1, wherein the gate-insulating film of said N-type MOS transistor consists of an insulating film formed simultaneously with the gate-insulating films of the other MOS transistors formed in said semiconductor substrate and an inter-layer insulating film formed on this insulating film, and a metal wiring layer forming said gate electrode is formed on said inter-layer insulating film.
Claim 4
Dependent Claim
63 words
The oscillator circuit according to claim 1, wherein the gate-insulating film of said P-type MOS transistor consists of an insulating film formed simultaneously with the gate-insulating films of the other MOS transistors formed in said semiconductor substrate and an inter-layer insulating film formed on this insulating film, and a metal wiring layer forming said gate electrode is formed on said inter-layer insulating film.
Claim 5
Dependent Claim
31 words
The oscillator circuit according to claim 2 or 3, wherein said inter-layer insulating film is formed simultaneously with inter-layer insulating films of the other MOS transistors formed on said semiconductor substrate.
Claim 6
Dependent Claim
21 words
The oscillator circuit according to claim 1, wherein said inverting logic circuit is enabled in accordance with an oscillation control signal.
Claim 7
Dependent Claim
47 words
The oscillator circuit according to claim 1, wherein the gate potentials of said N-type MOS transistor and said P-type MOS transistor are controlled by an oscillation control signal, and said N-type MOS transistor and said P-type MOS transistor are turned on or off at the same time.
Claim 8
Dependent Claim
94 words
The oscillator circuit according to claim 1, wherein the gate-insulating film of said N-type MOS transistor consists of a first insulating film formed simultaneously with the gate-insulating films of the other MOS transistors formed in said semiconductor substrate and a second insulating film formed on the first insulating film simultaneously with inter-layer insulating films of said other MOS transistors; a metal wiring layer forming said gate electrode is formed on said second insulating film; and a polycrystalline silicon layer, which is electrically floating, is formed on said first insulating film and in the inter-layer.
Claim 9
Dependent Claim
94 words
The oscillator circuit according to claim 1, wherein the gate-insulating film of said P-type MOS transistor consists of a first insulating film formed simultaneously with the gate-insulating films of the other MOS transistors formed in said semiconductor substrate and a second insulating film formed on the first insulating film simultaneously with inter-layer insulating films of said other MOS transistors; a metal wiring layer forming said gate electrode is formed on said second insulating film; and a polycrystalline silicon layer, which is electrically floating, is formed on said first insulating film and in the inter-layer.
References Cited (Backward Citations)
US4918408A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-06-17 | 1994-12-17 | 1995-06-18 | $2000.00 | Window Closed / Lapsed |
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