US3679916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled hysteresis integrated circuit switching circuit
Assignee: Landis and Gyr AG
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Filing: 1970-07-17
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Granted: 1972-07-25
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Expires: 1990-07-17
Abstract
Abstract A controlled hysteresis integrated circuit switching circuit wherein a bias signal and an input signal are connected in opposition across the input of an operational amplifier. A current source establishes the bias signal across a bias resistor. When the input signal overcomes the bias signal, the amplifier begins to change state. The output of the amplifier controls an active feedback network and, as the amplifier changes stage, a predetermined amount of current is switched to the bias resistor in opposition to that supplied by the current source to reduce the magnitude of the bias signal.
Inventors
- 👤 Holger Siebers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:08
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/56; H03K17/60; H03K3/00; H03K3/02; H03K3/023; H03K3/0233; H03K3/02337; H03K3/26; H03K3/28; H03K3/281; H03K3/286; H03K3/2893; H03K5/00; H03K5/15
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
165 words
In a controlled hysteresis integrated circuit switching circuit, the combination of an amplifier; biasing means connected to said amplifier for proviDing a bias signal for normally biasing said amplifier, said biasing means including a source of constant current and at least one resistive element connected in series therewith to develop said bias signal across said resistive element, said resistive element being connected in series with the input of said amplifier; an input circuit for receiving an input signal and including said biasing means, connected to said amplifier so that said amplifier begins to change state when said input signal overcomes said bias signal; and a differential amplifier circuit connected between the output of said amplifier and said biasing means for modifying said bias signal by causing current to flow through said resistive element in a predetermined amount in opposition to current flow from said source and in response to the change of state of said amplifier to thereby establish the hysteresis of said switching circuit.
Claim 2
Dependent Claim
165 words
In a controlled hysteresis integrated circuit switching circuit, the combination of an amplifier; biasing means connected to said amplifier for proviDing a bias signal for normally biasing said amplifier, said biasing means including a source of constant current and at least one resistive element connected in series therewith to develop said bias signal across said resistive element, said resistive element being connected in series with the input of said amplifier; an input circuit for receiving an input signal and including said biasing means, connected to said amplifier so that said amplifier begins to change state when said input signal overcomes said bias signal; and a differential amplifier circuit connected between the output of said amplifier and said biasing means for modifying said bias signal by causing current to flow through said resistive element in a predetermined amount in opposition to current flow from said source and in response to the change of state of said amplifier to thereby establish the hysteresis of said switching circuit.
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) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |