US3612912A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Schmitt trigger circuit with self-regulated arm voltage
Assignee: Unisys Corp
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Filing: 1970-01-14
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Granted: 1971-10-12
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Expires: 1990-01-14
Abstract
Abstract A Schmitt trigger circuit having an arm voltage which automatically increases in amplitude from a fixed minimum value in accordance with the amplitude of the input signal to the circuit. The input signal is applied directly to an inverting input terminal of a differential amplifier and the arm voltage, which comprises a component having a fixed value and a component having a value proportional to the amplitude of the input signal, is applied to a noninverting terminal of the differential amplifier. The output signal of the differential amplifier removes the arm voltage when the instantaneous value of the input signal is greater than that of the arm voltage and thereby causes the voltage at the noninverting terminal to decrease to a value corresponding to the base line value of the input signal.
Inventors
- 👤 John B Schwartz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:36
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/26; H03K3/28; H03K3/281; H03K3/286; H03K3/2893; H03K3/023; H03K3/0233; H03K3/02337
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
127 words
A self-arming switching circuit comprising: first means having at least two input terminals and an output terminal for producing in response to an amplitude varying input signal supplied to one input terminal thereof a bilevel output signal having an amplitude transition indicative of a selected amplitude of said input signal, second means coupled to the second input terminal of said first means and supplied with said input signal for establishing at said second terminal a voltage having a value dependent upon the instantaneous amplitude of said input signal, and nonlinear feedback means coupled between said output terminal and said second input terminal of said first means for making said amplitude transition independent of the amplitude of the signal produced at said output terminal of said first means.
Claim 2
Dependent Claim
127 words
A self-arming switching circuit comprising: first means having at least two input terminals and an output terminal for producing in response to an amplitude varying input signal supplied to one input terminal thereof a bilevel output signal having an amplitude transition indicative of a selected amplitude of said input signal, second means coupled to the second input terminal of said first means and supplied with said input signal for establishing at said second terminal a voltage having a value dependent upon the instantaneous amplitude of said input signal, and nonlinear feedback means coupled between said output terminal and said second input terminal of said first means for making said amplitude transition independent of the amplitude of the signal produced at said output terminal of said first means.
Claim 3
Dependent Claim
62 words
The circuit of claim 1 wherein said second means includes a device having a unidirectional current conduction characteristic supplied with said input signal for rectifying said input signal, and a capacitor coupled to both said device and said second terminal such that said voltage at said second terminal is made to increase in direct proportion to the amplitude of said input signal.
Claim 4
Dependent Claim
25 words
The circuit of claim 2 wherein said first means is a differential amplifier having first and second resistors connected serially across said two input terminals.
Claim 5
Dependent Claim
36 words
The circuit of claim 3 wherein said feedback means includes a transistor having its base terminal connected to said output terminal, and a diode connected between another terminal of said transistor and said second input terminal.
Claim 6
Dependent Claim
21 words
The circuit of claim 4 wherein said second means further includes a resistor coupling, in part, said capacitor to said diode.
Claim 7
Dependent Claim
154 words
A self-arming switching circuit comprising: first means having at least two input terminals and an output terminal for producing in response to an amplitude-varying input signal supplied to one input terminal thereof a bilevel output signal having an amplitude transition indicative of a selected amplitude of said input signal, second means supplied with said input signal, and coupled to the seconD input terminal of said first means and including, connected in the order mentioned, an impedance matching network, a voltage clamping network, means for producing a voltage proportional to the instantaneous amplitude of said input signal, an isolation circuit, and a device having a unidirectional current-conducting characteristic, and third means including said device and a transistor connected thereto, said transistor having its base electrode coupled to said output terminal of said first means for making said amplitude transition independent of the amplitude of the signal produced at said output terminal of said first means.
Claim 8
Dependent Claim
154 words
A self-arming switching circuit comprising: first means having at least two input terminals and an output terminal for producing in response to an amplitude-varying input signal supplied to one input terminal thereof a bilevel output signal having an amplitude transition indicative of a selected amplitude of said input signal, second means supplied with said input signal, and coupled to the seconD input terminal of said first means and including, connected in the order mentioned, an impedance matching network, a voltage clamping network, means for producing a voltage proportional to the instantaneous amplitude of said input signal, an isolation circuit, and a device having a unidirectional current-conducting characteristic, and third means including said device and a transistor connected thereto, said transistor having its base electrode coupled to said output terminal of said first means for making said amplitude transition independent of the amplitude of the signal produced at said output terminal of said first means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |