US4440980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overvoltage protection for a line circuit
Assignee: US Philips Corp
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Filing: 1981-04-06
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Granted: 1984-04-03
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Expires: 2001-04-06
Abstract
Abstract An overvoltage protection arrangement for preventing the occurrence of breakdown of a subscriber line control stage, independent of its structure and the integration technology used, by providing short-circuiting diodes in the control stage to prevent the occurrence of the overvoltage and providing voltage-limiting elements in those positions where overvoltage charge must be drained.
Inventors
- 👤 Pieter Bakker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:04
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/18; H04M19/00; H04M19/001
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
135 words
A control stage for a telephone subscriber's line for applying current in two directions to one wire of said subscribers's line comprising: an amplifier having an input and an output; said amplifier further having a first supply terminal (1-1) and a second supply terminal (1-2) for applying a supply current to said amplifier; a first diode (6) connected between said first supply terminal (1-1) and a first voltage source (2) and a second diode (7) connected between said second supply terminal (1-2) and a second voltage source (3), the supply current being applied to and discharged from said amplifier via said diodes; a third diode (11) connected between the output of said amplifier and said first supply terminal; and a fourth diode (12) connected between the output of said amplifier and said second supply terminal.
Claim 2
Dependent Claim
135 words
A control stage for a telephone subscriber's line for applying current in two directions to one wire of said subscribers's line comprising: an amplifier having an input and an output; said amplifier further having a first supply terminal (1-1) and a second supply terminal (1-2) for applying a supply current to said amplifier; a first diode (6) connected between said first supply terminal (1-1) and a first voltage source (2) and a second diode (7) connected between said second supply terminal (1-2) and a second voltage source (3), the supply current being applied to and discharged from said amplifier via said diodes; a third diode (11) connected between the output of said amplifier and said first supply terminal; and a fourth diode (12) connected between the output of said amplifier and said second supply terminal.
Claim 3
Dependent Claim
89 words
The invention according to claim 1 further comprising: an external resistor connected in series with the output of said amplifier and said one wire of the subscriber's line; a first voltage-limiting element (13) connected between that side of said third diode (11) which is not connected to the output of said amplifier and a point of constant potential; and a second voltage-limiting element (14) connected between that side of said fourth diode (12) which is not connected to the output of said amplifier and a point of constant potential.
Claim 4
Dependent Claim
110 words
The invention according to claim 1 further comprising: an external resistor connected in series with the output of said amplifier and said one wire of the subscriber's line; a first voltage-limiting element (13) and a fifth diode (21), one side of said first voltage-limiting element being connected to a point of constant potential and the other side being coupled to the output of said amplifier through said fifth diode; a second voltage-limiting element (14) and a sixth diode (22), one side of said second voltage-limiting element being connected to a point of constant potential and the other side being coupled to the output of said amplifier through said sixth diode.
Claim 5
Dependent Claim
130 words
The invention according to claim 2 wherein the input of said amplifier comprises a signal inverting input and a signal non-inverting input further comprising: a feedback circuit from that end of the external resistor that is not connected to the output of said amplifier to the signal non-inverting input of said amplifier; a seventh diode (16) connected between the signal non-inverting input of said amplifier and that side of said first voltage-limiting element (13) which is not connected to a point of constant potential; and an eighth diode (17) connected between the signal non-inverting input of said amplifier and that side of said second voltage-limiting element (14) which is not connected to a poit of constant potential, said seventh and eighth diodes being arranged such that they are normally non-conducting.
Claim 6
Dependent Claim
130 words
The invention according to claim 3 wherein the input of said amplifier comprises a signal inverting input and a signal non-inverting input further comprising: a feedback circuit from that end of the external resistor that is not connected to the output of said amplifier to the signal non-inverting input of said amplifier; a seventh diode (16) connected between the signal non-inverting input of said amplifier and that side of said first voltage-limiting element (13) which is not connected to a point of constant potential; and an eighth diode (17) connected between the signal non-inverting input of said amplifier and that side of said second voltage-limiting element (14) which is not connected to a point of constant potential, said seventh and eighth diodes being arranged such that they are normally non-conducting.
Claim 7
Dependent Claim
65 words
The invention according to claim 2 further comprising a third voltage-limiting element (20) one side of which is connected to that side of said first voltage-limiting element (13) which is not connected to a point of constant potential and the other side of which is coupled to that side of said second voltage-limiting element (14) which is not connected to a point of constant potential.
Claim 8
Dependent Claim
65 words
The invention according to claim 3 further comprising a third voltage-limiting element (20) one side of which is connected to that side of said first voltage-limiting element (13) which is not connected to a point of constant potential and the other side of which is coupled to that side of said second voltage-limiting element (14) which is not connected to a point of constant potential.
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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) | 1987-04-03 | 1987-10-03 | 1988-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-03 | 1991-10-03 | 1992-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-03 | 1995-10-03 | 1996-04-03 | $7700.00 | Window Closed / Lapsed |