US4539489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
CMOS Schmitt trigger circuit
Assignee: Motorola Solutions Inc
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Filing: 1983-06-22
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Granted: 1985-09-03
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Expires: 2003-06-22
Abstract
Abstract A CMOS Schmitt trigger which has two series-connected inverters uses both an input and an output signal to provide hysteresis. A pair of series-coupled transistors is coupled between a power supply terminal and a node between the two inverters. One of the transistors has a control electrode for receiving the input signal. The other of the transistors has a control electrode for receiving the output signal.
Inventors
- 👤 Herchel A. Vaughn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:32
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/353; H03K3/356; H03K3/3565
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
94 words
A Schmitt trigger comprising: a first inverter having an input for receiving an input signal, and an output coupled to a control node; a second inverter having an input coupled to the control node, and an output for providing an output signal; and a pair of series coupled transistors of a first conductivity type coupled between a first power supply terminal and the control node, with one of the pair having a control electrode for receiving the input signal and the other of the pair having a control electrode for receiving the output signal.
Claim 2
Dependent Claim
94 words
A Schmitt trigger comprising: a first inverter having an input for receiving an input signal, and an output coupled to a control node; a second inverter having an input coupled to the control node, and an output for providing an output signal; and a pair of series coupled transistors of a first conductivity type coupled between a first power supply terminal and the control node, with one of the pair having a control electrode for receiving the input signal and the other of the pair having a control electrode for receiving the output signal.
Claim 3
Dependent Claim
59 words
The Schmitt trigger circuit of claim 1 further comprising: a pair of series-coupled transistors of a second conductivity type coupled between a second power supply terminal and the control node with one of the pair having a control electrode for receiving the input signal and the other of the pair having a control electrode for receiving the output signal.
Claim 4
Dependent Claim
57 words
The Schmitt trigger circuit of claim 2 wherein the pair of series-coupled transistors of the first conductivity type are P channel transistors, the pair of series-coupled transistors of the second conductivity type are N Channel transistors, the first power supply terminal is for receiving a positive power supply voltage, and the second power supply terminal is ground.
References Cited (Backward Citations)
US4369381A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |