US5703765A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flyback converter having a regulated output voltage
Assignee: Siemens AG
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Filing: 1995-01-17
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Granted: 1997-12-30
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Expires: 2015-01-17
Abstract
Abstract PCT No. PCT/EP95/00163 Sec. 371 Date Jul. 18, 1996 Sec. 102(e) Date Jul. 18, 1996 PCT Filed Jan. 17, 1995 PCT Pub. No. WO95/20261 PCT Pub. Date Jul. 27, 1995Flyback converter has a regulating arrangement which is connected to an output and whose duty ratio is limited to a predetermined upper limit. A series circuit has a diode and an RC series circuit is connected to the rectifier diode of the main circuit (3) on the secondary side in order to supply the regulating arrangement with an auxiliary voltage which is greater than the output voltage. A further diode (44) leads from the series circuit to an output (a) of the auxiliary circuit (4). The flyback converter is suitable in particular for supplying ASICs, which require a relatively low supply voltage.
Inventors
- 👤 Josef Preis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:39
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/33561; H02M1/00; H02M1/0083; H02M1/009
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
273 words
A flyback converter, comprising: an electronic switch which is connected in series with a primary winding of a transformer in a main circuit on a primary side of the transformer, the electronic switch being controllable by a control device; on a secondary side of the transformer a main circuit which is connected to a secondary winding of the transformer, the main circuit having a first diode in a series path and an energy-storage capacitor in a subsequent parallel path, connected in parallel with an output in the transformer; a regulating arrangement connected to an output of the flyback converter, the regulating arrangement supplied with an auxiliary voltage, a duty ratio of the control voltage which controls the electronic switch being limited to a predetermined upper limit; an auxiliary circuit having an input connected to the first diode of the main circuit on the secondary side and the auxiliary circuit having one pole of an output connected to the input; the auxiliary circuit having an RC series circuit in a series path on the input side, a second diode in the downstream parallel path, a third diode in a series path following the parallel path, and a capacitor in parallel with the output; the regulating arrangement having an auxiliary voltage input supplied with an auxiliary voltage which is a sum of the output voltage of the flyback converter and the output voltage of the auxiliary circuit; the second diode polarized such that the second diode is reverse biased when the first diode is forward biased; the third diode polarized such that the third diode is reverse biased when the second diode is forward biased.
Claim 2
Dependent Claim
273 words
A flyback converter, comprising: an electronic switch which is connected in series with a primary winding of a transformer in a main circuit on a primary side of the transformer, the electronic switch being controllable by a control device; on a secondary side of the transformer a main circuit which is connected to a secondary winding of the transformer, the main circuit having a first diode in a series path and an energy-storage capacitor in a subsequent parallel path, connected in parallel with an output in the transformer; a regulating arrangement connected to an output of the flyback converter, the regulating arrangement supplied with an auxiliary voltage, a duty ratio of the control voltage which controls the electronic switch being limited to a predetermined upper limit; an auxiliary circuit having an input connected to the first diode of the main circuit on the secondary side and the auxiliary circuit having one pole of an output connected to the input; the auxiliary circuit having an RC series circuit in a series path on the input side, a second diode in the downstream parallel path, a third diode in a series path following the parallel path, and a capacitor in parallel with the output; the regulating arrangement having an auxiliary voltage input supplied with an auxiliary voltage which is a sum of the output voltage of the flyback converter and the output voltage of the auxiliary circuit; the second diode polarized such that the second diode is reverse biased when the first diode is forward biased; the third diode polarized such that the third diode is reverse biased when the second diode is forward biased.
Claim 3
Dependent Claim
20 words
The circuit arrangement as claimed in claim 1, wherein a limit of the duty ratio is at least approximately 0.5.
Claim 4
Dependent Claim
23 words
The circuit arrangement as claimed in claim 1, wherein a zener diode is arranged in parallel with the output of the auxiliary circuit.
Claim 5
Dependent Claim
31 words
The circuit arrangement as claimed in claim 1, wherein the supply voltage input of a regulator of the regulating arrangement is connected to the auxiliary voltage input of the regulating arrangement.
Claim 6
Dependent Claim
51 words
The circuit arrangement as claimed in claim 1, wherein a light-emitting diode of an optocoupler is connected to the output of the regulating arrangement, and wherein a series circuit which has the light-emitting diode of the optocoupler and a resistor is connected to the auxiliary voltage input of the regulating arrangement.
Claim 7
Dependent Claim
41 words
The circuit arrangement as claimed in claim 1, wherein the regulator is formed by a reference element, and wherein the control voltage output of the reference element is connected via a resistor to the auxiliary voltage input of the regulating arrangement.
Claim 8
Dependent Claim
30 words
The circuit arrangement as claimed in claim 1, wherein an output voltage of the flyback converter is less than 5 V, and the auxiliary voltage is at least 5 V.
Claim 9
Dependent Claim
287 words
A flyback converter, comprising: an electronic switch which is connected in series with a primary winding of a transformer in a main circuit on a primary side of the transformer, the electronic switch being controllable by a control device; on a secondary side of the transformer a main circuit which is connected to a secondary winding of the transformer, the main circuit having a first diode in a series path and an energy-storage capacitor in a subsequent parallel path, connected in parallel with an output in the transformer; a regulating arrangement connected to an output of the flyback converter, the regulating arrangement supplied with an auxiliary voltage, a duty ratio of the control voltage which controls the electronic switch being limited to a predetermined upper limit; an auxiliary circuit having an input connected to the first diode of the main circuit on the secondary side and the auxiliary circuit having one pole of an output connected to the input; the auxiliary circuit having an RC series circuit in a series path on the input side, a second diode in the downstream parallel path, a third diode in a series path following the parallel path, and a capacitor in parallel with the output; the regulating arrangement having an auxiliary voltage input supplied with an auxiliary voltage which is a sum of the output voltage of the flyback converter and the output voltage of the auxiliary circuit; the second diode polarized such that the second diode is reverse biased when the first diode is forward biased; the third diode polarized such that the third diode is reverse biased when the second diode is forward biased; and a zener diode arranged in parallel with the output of the auxiliary circuit.
Claim 10
Dependent Claim
287 words
A flyback converter, comprising: an electronic switch which is connected in series with a primary winding of a transformer in a main circuit on a primary side of the transformer, the electronic switch being controllable by a control device; on a secondary side of the transformer a main circuit which is connected to a secondary winding of the transformer, the main circuit having a first diode in a series path and an energy-storage capacitor in a subsequent parallel path, connected in parallel with an output in the transformer; a regulating arrangement connected to an output of the flyback converter, the regulating arrangement supplied with an auxiliary voltage, a duty ratio of the control voltage which controls the electronic switch being limited to a predetermined upper limit; an auxiliary circuit having an input connected to the first diode of the main circuit on the secondary side and the auxiliary circuit having one pole of an output connected to the input; the auxiliary circuit having an RC series circuit in a series path on the input side, a second diode in the downstream parallel path, a third diode in a series path following the parallel path, and a capacitor in parallel with the output; the regulating arrangement having an auxiliary voltage input supplied with an auxiliary voltage which is a sum of the output voltage of the flyback converter and the output voltage of the auxiliary circuit; the second diode polarized such that the second diode is reverse biased when the first diode is forward biased; the third diode polarized such that the third diode is reverse biased when the second diode is forward biased; and a zener diode arranged in parallel with the output of the auxiliary circuit.
Claim 11
Dependent Claim
20 words
The circuit arrangement as claimed in claim 8, wherein a limit of the duty ratio is at least approximately 0.5.
Claim 12
Dependent Claim
31 words
The circuit arrangement as claimed in claim 8, wherein the supply voltage input of a regulator of the regulating arrangement is connected to the auxiliary voltage input of the regulating arrangement.
Claim 13
Dependent Claim
51 words
The circuit arrangement as claimed in claim 8, wherein a light-emitting diode of an optocoupler is connected tot he output of the regulating arrangement, and wherein a series circuit which has the light-emitting diode of the optocoupler and a resistor is connected to the auxiliary voltage input of the regulating arrangement.
Claim 14
Dependent Claim
41 words
The circuit arrangement as claimed in claim 8, wherein the regulator is formed by a reference element, and wherein the control voltage output of the reference element is connected via a resistor to the auxiliary voltage input of the regulating arrangement.
Claim 15
Dependent Claim
30 words
The circuit arrangement as claimed in claim 8, wherein an output voltage of the flyback converter is less than 5 V, and the auxiliary voltage is at least 5 V.
Claim 16
Dependent Claim
295 words
A flyback converter, comprising: an electronic switch which is connected in series with a primary winding of a transformer in a main circuit on a primary side of the transformer, the electronic switch being controllable by a control device; on a secondary side of the transformer a main circuit which is connected to a secondary winding of the transformer, the main circuit having a first diode in a series path and an energy-storage capacitor in a subsequent parallel path, connected in parallel with an output in the transformer; a regulating arrangement connected to an output of the flyback converter, the regulating arrangement supplied with an auxiliary voltage, a duty ratio of the control voltage which controls the electronic switch being limited to a predetermined upper limit; an auxiliary circuit having an input connected to the first diode of the main circuit on the secondary side and the auxiliary circuit having one pole of an output connected to the input; the auxiliary circuit having an RC series circuit in a series path on the input side, a second diode in the downstream parallel path, a third diode in a series path following the parallel path, and a capacitor in parallel with the output; the regulating arrangement having an auxiliary voltage input supplied with an auxiliary voltage which is a sum of the output voltage of the flyback converter and the output voltage of the auxiliary circuit; the second diode polarized such that the second diode is reverse biased when the first diode is forward biased; the third diode polarized such that the third diode is reverse biased when the second diode is forward biased; and the supply voltage input of a regulator of the regulating arrangement connected to the auxiliary voltage input of the regulating arrangement.
Claim 17
Dependent Claim
295 words
A flyback converter, comprising: an electronic switch which is connected in series with a primary winding of a transformer in a main circuit on a primary side of the transformer, the electronic switch being controllable by a control device; on a secondary side of the transformer a main circuit which is connected to a secondary winding of the transformer, the main circuit having a first diode in a series path and an energy-storage capacitor in a subsequent parallel path, connected in parallel with an output in the transformer; a regulating arrangement connected to an output of the flyback converter, the regulating arrangement supplied with an auxiliary voltage, a duty ratio of the control voltage which controls the electronic switch being limited to a predetermined upper limit; an auxiliary circuit having an input connected to the first diode of the main circuit on the secondary side and the auxiliary circuit having one pole of an output connected to the input; the auxiliary circuit having an RC series circuit in a series path on the input side, a second diode in the downstream parallel path, a third diode in a series path following the parallel path, and a capacitor in parallel with the output; the regulating arrangement having an auxiliary voltage input supplied with an auxiliary voltage which is a sum of the output voltage of the flyback converter and the output voltage of the auxiliary circuit; the second diode polarized such that the second diode is reverse biased when the first diode is forward biased; the third diode polarized such that the third diode is reverse biased when the second diode is forward biased; and the supply voltage input of a regulator of the regulating arrangement connected to the auxiliary voltage input of the regulating arrangement.
Claim 18
Dependent Claim
20 words
The circuit arrangement as claimed in claim 14, wherein a limit of the duty ration is at least approximately 0.5.
Claim 19
Dependent Claim
23 words
The circuit arrangement as claimed in claim 14, wherein a zener diode is arranged in parallel with the output of the auxiliary circuit.
Claim 20
Dependent Claim
51 words
The circuit arrangement as claimed in claim 14, wherein a light-emitting diode of an optocoupler is connected tot he output of the regulating arrangement, and wherein a series circuit which has the light-emitting diode of the optocoupler and a resistor is connected to the auxiliary voltage input of the regulating arrangement.
Claim 21
Dependent Claim
41 words
The circuit arrangement as claimed in claim 14, wherein the regulator is formed by a reference element, and wherein the control voltage output of the reference element is connected via a resistor to the auxiliary voltage input of the regulating arrangement.
Claim 22
Dependent Claim
30 words
The circuit arrangement as claimed in claim 14, wherein an output voltage of the flyback converter is less than 5 V, and the auxiliary voltage is at least 5 V.
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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) | 2000-12-29 | 2001-06-30 | 2001-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-12-29 | 2005-06-30 | 2005-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-12-29 | 2009-06-30 | 2009-12-30 | $7700.00 | Window Closed / Lapsed |