US3818306A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilized power supply with transformer isolation
Assignee: Italtel SpA
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Filing: 1973-02-20
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Granted: 1974-06-18
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Expires: 1993-02-20
Abstract
Abstract A storage capacitor, periodically charged through a chopping transistor via an inductance which during cutoff of the transistor maintains the flow of charging current by way of a diode, energizes an output terminal through a d-c/a-c converter, a transformer and a rectifier in tandem therewith. A sensor responsive to the voltage (or current) on that terminal feeds one input of an analog-type first differential amplifier whose other input receives a constant reference voltage (or current) and whose output constitutes an error signal. A binary-type second differential amplifier compares this error signal with the output of a sawtooth-wave generator and, on detecting a coincidence therebetween, energizes a differentiation circuit which generates a turn-on pulse for the switching transistor; a turn-off pulse for that transistor is periodically produced by a gating circuit which also triggers the sawtooth-wave generator. Two pulse transformers galvanically separate the gating circuit and the switching transistor from the sawtooth-voltage generator and the associated amplifier and differentiation circuit.
Inventors
- 👤 R Marini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:25
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156; A; A47; A47L; A47L15/00; A47L15/42; A47L15/4246; A47L15/4248; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/33507; H02M3/33523; H02M1/00; H02M1/0067; H02M1/007; H02M3/33569; H02M3/33573
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
341 words
A stabilized power supply comprising: a storage capacitor; a high-voltage charging circuit for said capacitor including an inductance in series therewith; electronic switch means in said charging circuit; control means including a generator of a sloping wave establishing a constant operating cycle; diode means connected to maintain the flow of a charging current into said capacitor via said inductance upon the opening of said switch means; a d-c/a-c converter connected in a discharge path for said capacitor; a low-voltage load circuit including rectifier means inductively coupled to said converter for energization thereby; sensing means connected to the output of said rectifier means for measuring the magnitude of an electrical variable in said load circuit; first comparison means connected to said sensing means and to a source of reference quantity for generating an error signal of a magnitude proportional to the difference between said variable and said reference quantity; second comparison means connected to said first comparison means and to said generator for detecting a coincidence between said sloping wave and said error signal; a source of periodically recurring gating pulses connected to said switch means for establishing a first operating condition thereof; a differentiation circuit connected to said second comparison means for generating a succession of control pulses for said switch means upon said sloping wave reaching the level of said error signal; a first pulse transformer coupling said differentiation circuit to said switch means for establishing a second operating condition thereof in response to said control pulses, the variable spacing of said Control pulses from said gating pulses in successive operating cycles determining a duty ratio for said switch means varying inversely with the magnitude of said error signal to minimize the latter; and a second pulse transformer coupling said source to said generator for triggering same at the frequency of said gating pulses with galvanic isolation of said capacitor, said switch means and said source, on the one hand, from said load circuit, said sensing means, said first and second comparison means and said generator, on the other hand.
Claim 2
Dependent Claim
341 words
A stabilized power supply comprising: a storage capacitor; a high-voltage charging circuit for said capacitor including an inductance in series therewith; electronic switch means in said charging circuit; control means including a generator of a sloping wave establishing a constant operating cycle; diode means connected to maintain the flow of a charging current into said capacitor via said inductance upon the opening of said switch means; a d-c/a-c converter connected in a discharge path for said capacitor; a low-voltage load circuit including rectifier means inductively coupled to said converter for energization thereby; sensing means connected to the output of said rectifier means for measuring the magnitude of an electrical variable in said load circuit; first comparison means connected to said sensing means and to a source of reference quantity for generating an error signal of a magnitude proportional to the difference between said variable and said reference quantity; second comparison means connected to said first comparison means and to said generator for detecting a coincidence between said sloping wave and said error signal; a source of periodically recurring gating pulses connected to said switch means for establishing a first operating condition thereof; a differentiation circuit connected to said second comparison means for generating a succession of control pulses for said switch means upon said sloping wave reaching the level of said error signal; a first pulse transformer coupling said differentiation circuit to said switch means for establishing a second operating condition thereof in response to said control pulses, the variable spacing of said Control pulses from said gating pulses in successive operating cycles determining a duty ratio for said switch means varying inversely with the magnitude of said error signal to minimize the latter; and a second pulse transformer coupling said source to said generator for triggering same at the frequency of said gating pulses with galvanic isolation of said capacitor, said switch means and said source, on the one hand, from said load circuit, said sensing means, said first and second comparison means and said generator, on the other hand.
Claim 3
Dependent Claim
42 words
A power supply as defined in claim 1 wherein said switch means comprises a transistor provided with an ancillary switch for turning on said transistor in response to said control pulses and turning off said transistor in response to said gating pulses.
Claim 4
Dependent Claim
27 words
A power supply as defined in claim 1 wherein said first comparison means comprises a differential analog amplifier, said second comparison means comprising a differential binary amplifier.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |