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US5042065A Expired / Lapsed US ⏱️ 0.0 years remaining

Resetting circuit in a key-telephone system

Assignee: Samsung Electronics Co Ltd
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Filing: 1989-07-31
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Granted: 1991-08-20
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Expires: 2009-07-31
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Abstract

Abstract There is disclosed a resetting circuit of a key telephone system (KTS) capable of preventing data error caused by unstable power supply and instantaneous power-off of a key system unit (KSU), by adjusting a DC voltage of the key telehpone system, said DC voltage is applied to a reset terminal of a microprocessor in the key telephone system. The invention includes a power supply for supplying power to the KSU and KTS, a microprocessor for controlling the overall operation of the KTS, a first detecting means for detecting the voltage change of a first voltage Vcc1, and a second detecting means for detecting the voltage change of a second voltage Vcc2.

Inventors

  • 👤 Sung-Taek Kim

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 14:06
CPC Classifications
H; H04; H04M; H04M19/00; H04M19/08; H04M9/00; H04M9/002

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 88 words
A resetting circuit in a key-phone system including a power supply in a key system unit, a voltage regulating means supplying a first and second voltage to a microprocessor, and a data link receiving said first voltage, said circuit comprising: a reset signal generator for detecting a voltage state of the first voltage and a voltage state of the second voltage which is produced from the voltage regulating means, and generating a reset signal in order to reset the microprocessor if the first voltage's detected state is unstable.
Claim 2
Dependent Claim 88 words
A resetting circuit in a key-phone system including a power supply in a key system unit, a voltage regulating means supplying a first and second voltage to a microprocessor, and a data link receiving said first voltage, said circuit comprising: a reset signal generator for detecting a voltage state of the first voltage and a voltage state of the second voltage which is produced from the voltage regulating means, and generating a reset signal in order to reset the microprocessor if the first voltage's detected state is unstable.
Claim 3
Dependent Claim 75 words
The resetting circuit as set forth in claim 1, wherein said reset signal generator comprises: a first detecting means for detecting a state of the first voltage which is produced from the voltage regulating means; a second detecting means for detecting a state of the second voltage which is produced from the voltage regulator means; and a gate for generating the reset signal by receiving the voltages detected by said first and second detecting means.
Claim 4
Dependent Claim 27 words
The resetting circuit as set forth in claim 2, wherein said gate is an AND gate whose output is connected to a reset terminal of the microprocessor.
Claim 5
Dependent Claim 91 words
A resetting circuit in a key-phone system including a power supply in a key system unit, voltage regulating means for supplying a first and second voltage to a microprocessor, and a data link receiving said first voltage, said circuit comprising: first means for receiving said first voltage and outputting a delayed first voltage; second means for receiving said second voltage and outputting a delayed second voltage as a reference voltage; and gate means for receiving said delayed first voltage and said reference voltage and for outputting reset signal to said microprocessor.
Claim 6
Dependent Claim 91 words
A resetting circuit in a key-phone system including a power supply in a key system unit, voltage regulating means for supplying a first and second voltage to a microprocessor, and a data link receiving said first voltage, said circuit comprising: first means for receiving said first voltage and outputting a delayed first voltage; second means for receiving said second voltage and outputting a delayed second voltage as a reference voltage; and gate means for receiving said delayed first voltage and said reference voltage and for outputting reset signal to said microprocessor.
Claim 7
Dependent Claim 33 words
The resetting circuit as set forth in claim 4, wherein said first means comprises a first resistor and a first capacitor, and said second means comprises a second resistor and a second capacitor.
Claim 8
Dependent Claim 17 words
The resetting circuit as set forth in claim 4, wherein said gate means comprises an AND gate.
Claim 9
Dependent Claim 17 words
The resetting circuit as set forth in claim 5, wherein said gate means comprises an AND gate.
Claim 10
Dependent Claim 49 words
The resetting circuit as set forth in claim 5, wherein said gate means comprises an AND gate having a first input connected to a node between said first resistor and said first capacitor and a second input connected to a node between said second resistor and said second capacitor.
Claim 11
Dependent Claim 32 words
The resetting circuit as set forth in claim 8, further comprising a third resistor connected in parallel to said first capacitor, and a fourth resistor connected in parallel to said second capacitor.
Claim 12
Dependent Claim 96 words
A resetting circuit in a key-phone system including a power supply in a key system unit, voltage regulating means for supplying a first and second voltage to a microprocessor, and a data link receiving said first voltage, said circuit comprising: a reset generator for comparing the voltage state of the first voltage to the voltage state of the second voltage and for generating a reset signal in order to reset said microprocessor whenever the voltage state of said first voltage falls to a level lower that the level of the voltage state of said second voltage.
Claim 13
Dependent Claim 96 words
A resetting circuit in a key-phone system including a power supply in a key system unit, voltage regulating means for supplying a first and second voltage to a microprocessor, and a data link receiving said first voltage, said circuit comprising: a reset generator for comparing the voltage state of the first voltage to the voltage state of the second voltage and for generating a reset signal in order to reset said microprocessor whenever the voltage state of said first voltage falls to a level lower that the level of the voltage state of said second voltage.
Claim 14
Dependent Claim 52 words
The resetting circuit as set forth in claim 10, wherein said reset signal generator comprises: first delay means for responding to said first voltage, second delay means for responding to said second voltage, and gate means for receiving the outputs of said first and second delay means and providing said reset signal.
Claim 15
Dependent Claim 17 words
The resetting circuit as set forth in claim 10, wherein said gate means comprises an AND gate.

References Cited (Backward Citations)

JPS5899091A Cited
JPS60196096A Cited
US4887293A Cited
JPS62200852A Cited
JPH01151347A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-08-19 1995-02-18 1995-08-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-08-19 1999-02-18 1999-08-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-08-19 2003-02-18 2003-08-20 $7700.00 Window Closed / Lapsed

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