Patent US4964406A successfully refreshed from Google Patents.
US4964406A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Implantable cardiac defibrillator employing a switched capacitor stage having a non-50/50 duty cycle
Assignee: Pacesetter Inc
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Filing: 1989-05-19
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Granted: 1990-10-23
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Expires: 2009-05-19
Abstract
Abstract An implantable cardiac defibrillator employing a switched capacitor stage wherein the switches are clocked in a non-50%/50% ratio such that an operational amplifier has greater than 50% of the clock period to acquire the desired voltage and less than 50% of the clock period to hold the acquired voltage, thereby allowing the circuit to run at an overall lower current drain.
Inventors
- 👤 Kenneth J. Carroll
- 👤 Benjamin D. Pless
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:18
CPC Classifications
A; A61; A61N; A61N1/00; A61N1/18; A61N1/32; A61N1/36; A61N1/362; A61N1/3621; A61N1/3622; A61N1/38; A61N1/39; A61N1/3925; A61N1/3931
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
107 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; said sensing means including switched capacitor means having switches clocked by first and second control signals with a non-50/50 percent duty cycle; said switched capacitor means comprising operational amplifier means having an inverting input terminal, a non-inverting input terminal and an output terminal; said operational amplifier means having greater than 50 percent of the clock period to acquire a desired voltage on the output terminal and less than 50 percent of the clock period to hold the acquired voltage.
Claim 2
Dependent Claim
107 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; said sensing means including switched capacitor means having switches clocked by first and second control signals with a non-50/50 percent duty cycle; said switched capacitor means comprising operational amplifier means having an inverting input terminal, a non-inverting input terminal and an output terminal; said operational amplifier means having greater than 50 percent of the clock period to acquire a desired voltage on the output terminal and less than 50 percent of the clock period to hold the acquired voltage.
Claim 3
Dependent Claim
33 words
An implantable medical device as claimed in claim 1, wherein said first control signal has approximately a 30/70 percent duty cycle and said second control signal has approximately a 70/30 percent duty cycle.
Claim 4
Dependent Claim
48 words
An implantable medical device as claimed in claim 1, wherein said first control signal is at a high logic level for less than 50 percent of the clock period and said second control signal is at a high logic level greater than 50 percent of the clock period.
Claim 5
Dependent Claim
111 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; means for storing a charge; means for discharging said storage means to shock the heart via the electrode means; said sensing means including switched capacitor means formed of operational amplifier means and switch means, said switch means being clocked by first and second control signals with a non-50/50 percent duty cycle; said operational amplifier means having greater than 50 percent of the clock period to acquire a desired voltage and less than 50 percent of the clock period to hold the acquired voltage.
Claim 6
Dependent Claim
111 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; means for storing a charge; means for discharging said storage means to shock the heart via the electrode means; said sensing means including switched capacitor means formed of operational amplifier means and switch means, said switch means being clocked by first and second control signals with a non-50/50 percent duty cycle; said operational amplifier means having greater than 50 percent of the clock period to acquire a desired voltage and less than 50 percent of the clock period to hold the acquired voltage.
Claim 7
Dependent Claim
33 words
An implantable medical device as claimed in claim 4, wherein said first control signal has approximately a 30/70 percent duty cycle and said second control signal has approximately a 70/30 percent duty cycle.
Claim 8
Dependent Claim
48 words
An implantable medical device as claimed in claim 4, wherein said first control signal is at a high logic level for less than 50 percent of the clock period and said second control signal is at a high logic level greater than 50 percent of the clock period.
Claim 9
Dependent Claim
74 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; said sensing means including switched capacitor means having switches clocked by first and second control signals with a non-50/50 percent duty cycle; and said first control signal having approximately a 30/70 percent duty cycle and said second control signal has approximately a 70/30 percent duty cycle.
Claim 10
Dependent Claim
74 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; said sensing means including switched capacitor means having switches clocked by first and second control signals with a non-50/50 percent duty cycle; and said first control signal having approximately a 30/70 percent duty cycle and said second control signal has approximately a 70/30 percent duty cycle.
Claim 11
Dependent Claim
98 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; means for storing a charge; means for discharging said storage means to shock the heart; said sensing means including switched capacitor means formed of operational amplifier means and switch means, said switch means being clocked by first and second control signals with a non-50/50 percent duty cycle; said first control signal having approximately a 30/70 percent duty cycle and said second control signal has approximately a 70/30 percent duty cycle.
Claim 12
Dependent Claim
98 words
An implantable medical device comprising: electrode means adapted for coupling to a patient's heart; sensing means having inputs connected to said electrode means for sensing cardiac electrical signals; means for storing a charge; means for discharging said storage means to shock the heart; said sensing means including switched capacitor means formed of operational amplifier means and switch means, said switch means being clocked by first and second control signals with a non-50/50 percent duty cycle; said first control signal having approximately a 30/70 percent duty cycle and said second control signal has approximately a 70/30 percent duty cycle.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-22 | 1994-04-23 | 1994-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-22 | 1998-04-23 | 1998-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-22 | 2002-04-23 | 2002-10-23 | $7700.00 | Window Closed / Lapsed |