US5367447A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal separation circuit
Assignee: Murata Manufacturing Co Ltd
•
Filing: 1993-06-01
•
Granted: 1994-11-22
•
Expires: 2013-06-01
Abstract
Abstract A signal separation circuit for separating direct current power on a telephone with a transistor. A CPU, which includes an A/D converter, is connected to detect the emitter-collector voltage of the transistor, and to control the base current of the transistor to maintain the emitter-collector voltage constant.
Inventors
- 👤 Satosi Sakuragi
- 👤 Takashi Kuroda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:43
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/337; H02M3/3372; H02M3/3374
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
71 words
A signal separation circuit for separating a direct-current power from a signal having a direct current component and an alternate-current component by passing said signal through the collector-emitter path of a transistor, comprising: a voltage detecting means for detecting the emitter-collector voltage of said transistor; and a base current control means for controlling the base current of said transistor to hold said emitter-collector voltage of said transistor at a predetermined value.
Claim 2
Dependent Claim
71 words
A signal separation circuit for separating a direct-current power from a signal having a direct current component and an alternate-current component by passing said signal through the collector-emitter path of a transistor, comprising: a voltage detecting means for detecting the emitter-collector voltage of said transistor; and a base current control means for controlling the base current of said transistor to hold said emitter-collector voltage of said transistor at a predetermined value.
Claim 3
Dependent Claim
85 words
A signal separation circuit for separating direct-current power from a signal having a direct current component and an alternate-current component, comprising a source of said signal, a transistor having an emitter-collector current path and a base, a load circuit, means connecting said source to said load circuit via said emitter-collector path of said transistor, means for detecting the emitter-collector voltage of said transistor; and means for controlling the base current of said transistor to hold said emitter-collector voltage of said transistor at a predetermined value.
Claim 4
Dependent Claim
85 words
A signal separation circuit for separating direct-current power from a signal having a direct current component and an alternate-current component, comprising a source of said signal, a transistor having an emitter-collector current path and a base, a load circuit, means connecting said source to said load circuit via said emitter-collector path of said transistor, means for detecting the emitter-collector voltage of said transistor; and means for controlling the base current of said transistor to hold said emitter-collector voltage of said transistor at a predetermined value.
Claim 5
Dependent Claim
84 words
A signal separation circuit for separating direct-current power from a signal having a direct current component and an alternate-current component, comprising a source of said signal, a transistor having an emitter-collector current path and a base, a load circuit, means connecting said source to said load circuit via said emitter-collector path of said transistor, and a CPU connected to measure the emitter-collector voltage of said transistor and to control the base current of said transistor to hold said emitter-collector voltage at a predetermined value.
Claim 6
Dependent Claim
84 words
A signal separation circuit for separating direct-current power from a signal having a direct current component and an alternate-current component, comprising a source of said signal, a transistor having an emitter-collector current path and a base, a load circuit, means connecting said source to said load circuit via said emitter-collector path of said transistor, and a CPU connected to measure the emitter-collector voltage of said transistor and to control the base current of said transistor to hold said emitter-collector voltage at a predetermined value.
Claim 7
Dependent Claim
44 words
The signal separation circuit of claim 3 wherein said means connecting said source to said load circuit comprises a rectifier and hook switch, and further comprising a capacitor connected between said hook switch and emitter-collector path of said transistor for outputting said alternate-current component.
Claim 8
Dependent Claim
27 words
The signal separation circuit of claim 3 wherein said CPU has a AD converter with inputs connected to detect the emitter and collector voltages of said transistor.
References Cited (Backward Citations)
US4410766A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-21 | 1998-05-23 | 1998-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-21 | 2002-05-23 | 2002-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-21 | 2006-05-23 | 2006-11-22 | $7700.00 | Window Closed / Lapsed |