US3586989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time shared amplifiers
Assignee: Gemalto Terminals Ltd
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Filing: 1969-12-04
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Granted: 1971-06-22
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Expires: 1989-12-04
Abstract
Abstract In known time shared amplifiers, voltage drift stabilization is effected by periodically shorting the amplifier output to the amplifier input while connecting the input terminal to a reference potential to charge an input character, which then supplies a corrective offset. This does not however effect current drift stabilization, which is effected according to the invention by a capacitor and resistor in series between the amplifier input and the reference potential. The amplifier output is now periodically shorted to the junction of the resistor and capacitor. The charge established on the capacitor then supplies an offset current through the resistor.
Inventors
- 👤 Desmond Wheable
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:04
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/30; H03F1/303; H03F3/00; H03F3/45; H03F3/45071; H03F3/45479
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
131 words
A time-shared amplifier comprising an amplifier having an input and output, an input impedance connected to said amplifier input, an input terminal for receiving an input electrical signal, a source of a reference electrical signal, first switch means and control means therefor operative to effectively connect said input terminal and reference source alternately to said input impedance during successive operative and correcting phases, a resistor connected at one end to said amplifier input, a capacitor having one end connected to the other end of said resistor and having the other end connected to said reference source, and further switch means responsive to said control means to connect said amplifier output to the junction of said one end of said capacitor with said other end of said resistor during said correcting phases.
Claim 2
Dependent Claim
131 words
A time-shared amplifier comprising an amplifier having an input and output, an input impedance connected to said amplifier input, an input terminal for receiving an input electrical signal, a source of a reference electrical signal, first switch means and control means therefor operative to effectively connect said input terminal and reference source alternately to said input impedance during successive operative and correcting phases, a resistor connected at one end to said amplifier input, a capacitor having one end connected to the other end of said resistor and having the other end connected to said reference source, and further switch means responsive to said control means to connect said amplifier output to the junction of said one end of said capacitor with said other end of said resistor during said correcting phases.
Claim 3
Dependent Claim
14 words
A time-shared amplifier according to claim 1, wherein said input impedance is a capacitor.
Claim 4
Dependent Claim
45 words
A time-shared amplifier according to claim 1, wherein said first switch means comprises two switch means respectively connecting said input terminal and said reference source to said input impedance and responsive to said control means to open and close out of phase with each other.
Claim 5
Dependent Claim
52 words
A time-shared amplifier according to claim 1, wherein said first switch means comprise a switch means connecting said reference source to said input impedance and responsive to said control means to close during said correcting phases, the amplifier further comprising an input resistor connected between said input terminal and said input impedance.
Claim 6
Dependent Claim
52 words
A time-shared amplifier according to claim 1, comprising first and second output terminals connected respectively to said amplifier output and said reference source, a potential divider connected across said output terminals and having an intermediate tap, and first and second input terminals connected respectively to said input impedance and said intermediate tap.
Claim 7
Dependent Claim
45 words
A time-shared amplifier according to claim 5, comprising an output switch means connected between said amplifier output and said first output terminal and responsive to said control means to open during said correcting phases, and a further capacitor connected in parallel with said potential divider.
Claim 8
Dependent Claim
20 words
A time-shared amplifier according to claim 6, comprising a buffer amplifier connected between said further capacitor and said potential divider.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-21 | 1974-12-21 | 1975-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-21 | 1978-12-21 | 1979-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-21 | 1982-12-21 | 1983-06-22 | $7700.00 | Window Closed / Lapsed |