Patents by Inventor Sergiu Silvian

Sergiu Silvian has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8209005
    Abstract: Constant voltage or current is applied to high-voltage leads to determine impedance across medical device leads. Thyristors are used for upper switching components in an H-bridge. Current is sourced into a thyristor's gate from a ground-referenced source. This current then passes from the gate to the cathode and out to the patient. By keeping the current sufficiently low, the thyristors will not conduct from the anode to the cathode. Current passes through the thyristor, lead and patient and is sensed as it returns from the other lead. The sensed current is used to regulate the injected current. Pulses of constant current on the order of tens of milliamperes can be injected and the resulting voltage can be measured. Alternatively, a constant voltage can be applied and the resulting current can be measured to determine lead impedance.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: June 26, 2012
    Assignee: Pacesetter, Inc.
    Inventors: J. Christopher Moulder, George I. Isaac, Sergiu Silvian
  • Patent number: 7136703
    Abstract: A programmer for implantable stimulation devices and surface ECG system in wireless communication with each other. A self-powered ECG monitor with conventional surface electrodes transceives signals from and to a programmer provided with a radio frequency transceiver to eliminate hardwiring between the surface electrodes and the programmer. The system reduces the need for supply line frequency filtering and isolation circuitry to protect against high voltage defibrillation shocks.
    Type: Grant
    Filed: April 16, 2002
    Date of Patent: November 14, 2006
    Assignee: Pacesetter, Inc.
    Inventors: Armando M. Cappa, Sergiu Silvian, Paul A. Levine
  • Patent number: 6968231
    Abstract: A high voltage converter circuit for an implantable cardiac device. The circuit includes a plurality of transistors that are connected in parallel to a battery and the primary winding of a transformer. A switching element is connected to the circuit so as to periodically connect and disconnect the capacitors to the primary winding of the transformer to thereby induce the capacitors to be charged and periodically discharged across the transformer into charging capacitors. A circuit also preferably includes a disconnect circuit that will disconnect the capacitors from the battery during periods of non-use to inhibit unwanted dissipation of the battery's energy.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: November 22, 2005
    Assignee: Pacesetter, Inc.
    Inventors: Sergiu Silvian, Gabriel A. Mouchawar
  • Patent number: 6577900
    Abstract: A telemetry system for use in an implantable device that communicates with an external programmer, includes a coil, a timing circuit connected to the coil, and a coil driver circuit that reverts at least part of the expanded energy back to the power source. The timing circuit generates two control signals SC1 and SC2, and is comprised of four switches S1, S2, S3, S4 that are connected across the power source and the coil, and that are selectively energized by the control signals SC1 and SC2. The control signal SC1 energizes switches S1 and S4 to close, with the switches S2 and S3 open, causing the coil to become a load across the power source and to store energy therefrom. Upon the expiration of the control signal SC1, the control signal SC2 triggers switches S2 and S3 to close with the switches S1 and S4 open, causing the coil to discharge the stored energy through the power source, charging it.
    Type: Grant
    Filed: May 29, 2001
    Date of Patent: June 10, 2003
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 6577898
    Abstract: A bi-directional telemetry system includes an implanted unit that allows a high-speed transfer of digital data with minimal complexity of the electronic circuitry. A corresponding external unit is capable of decoding the high-data-rate transmitted information and, in turn, communicates with the implanted unit using pulse amplitude modulation. The data transmission rate of the implanted unit to the external device is 32 kbps, a four-fold increase over conventional data transmission rates, without increasing the carrier frequency. To this end, the implanted unit using a modified implementation of the quadrature amplitude modulation (QAM) method that generates the required symbols from readily available squarewave signals. Simulated sinewaves are generated within the transmitter by an inverting amplifier stage with variable input resistance determined by a pair of switches that are ultimately controlled by 16 k and 32 k clocks in the implanted unit.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: June 10, 2003
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 6522920
    Abstract: A protection device for use in an implantable medical device such as an ICD that communicates with an external programmer. The protection device includes one or more control blocks that inhibit gate triggers for the switching elements (IGBTs) of an H-bridge whenever the drive voltage for these switching elements falls below a pre-determined level. Each control block provides a controlled path to charge the IGBT gate when triggering is required and, importantly, when the gate drive voltage is above a predetermined threshold. The control block further prevents inadvertent or spurious triggering and protects the gate circuitry of the switching elements by providing a low impedance path between the gates and sources of the IGBTs when the latter switching elements are intended to be turned OFF. Additionally, the control blocks protect the IGBTs from over-voltage effects by clamping the output of the gate trigger with a shunt regulator circuit.
    Type: Grant
    Filed: December 11, 2000
    Date of Patent: February 18, 2003
    Assignee: Pacesetter, Inc.
    Inventors: Sergiu Silvian, Wayne A. Morgan
  • Publication number: 20020183799
    Abstract: A bi-directional telemetry system includes an implanted unit that allows a high-speed transfer of digital data with minimal complexity of the electronic circuitry. A corresponding external unit is capable of decoding the high-data-rate transmitted information and, in turn, communicates with the implanted unit using pulse amplitude modulation. The data transmission rate of the implanted unit to the external device is 32 kbps, a four-fold increase over conventional data transmission rates, without increasing the carrier frequency. To this end, the implanted unit using a modified implementation of the quadrature amplitude modulation (QAM) method that generates the required symbols from readily available squarewave signals. Simulated sinewaves are generated within the transmitter by an inverting amplifier stage with variable input resistance determined by a pair of switches that are ultimately controlled by 16 k and 32 k clocks in the implanted unit.
    Type: Application
    Filed: April 26, 2001
    Publication date: December 5, 2002
    Inventor: Sergiu Silvian
  • Patent number: 6477414
    Abstract: The transformer assembly is coupled between a power supply and a pulse delivery circuit of the implantable cardiac stimulation device for charging a pair of defibrillation capacitors for delivering defibrillation pulses. The power transformer assembly is formed from a printed circuit board (PCB) having a set of transformer coil turns embedded therein and a transformer core mounted adjacent to the windings of the PCB. By embedding the coil of the transformer within the PCB, the transformer may be more easily integrated with other components of the stimulation device so that the overall size of the stimulation device may be reduced. Moreover, the use of a PCB helps avoid reliability problems that might otherwise occur in the fabrication, assembly and operation of the device. In one specific configuration described herein, the transformer assembly includes a primary and two secondary transformers. The primary transformer is used as a flyback transformer for charging the pair of defibrillation capacitors.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: November 5, 2002
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Publication number: 20020161406
    Abstract: The transformer assembly is coupled between a power supply and a pulse delivery circuit of the implantable cardiac stimulation device for charging a pair of defibrillation capacitors for delivering defibrillation pulses. The power transformer assembly is formed from a printed circuit board (PCB) having a set of transformer coil turns embedded therein and a transformer core mounted adjacent to the windings of the PCB. By embedding the coil of the transformer within the PCB, the transformer may be more easily integrated with other components of the stimulation device so that the overall size of the stimulation device may be reduced. Moreover, the use of a PCB helps avoid reliability problems that might otherwise occur in the fabrication, assembly and operation of the device. In one specific configuration described herein, the transformer assembly includes a primary and two secondary transformers. The primary transformer is used as a flyback transformer for charging the pair of defibrillation capacitors.
    Type: Application
    Filed: April 26, 2001
    Publication date: October 31, 2002
    Inventor: Sergiu Silvian
  • Publication number: 20020072769
    Abstract: A protection device for use in an implantable medical device such as an ICD that communicates with an external programmer. The protection device includes one or more control blocks that inhibit gate triggers for the switching elements (IGBTs) of an H-bridge whenever the drive voltage for these switching elements falls below a pre-determined level. Each control block provides a controlled path to charge the IGBT gate when triggering is required and, importantly, when the gate drive voltage is above a predetermined threshold. The control block further prevents inadvertent or spurious triggering and protects the gate circuitry of the switching elements by providing a low impedance path between the gates and sources of the IGBTs when the latter switching elements are intended to be turned OFF. Additionally, the control blocks protect the IGBTs from over-voltage effects by clamping the output of the gate trigger with a shunt regulator circuit.
    Type: Application
    Filed: December 11, 2000
    Publication date: June 13, 2002
    Inventors: Sergiu Silvian, Wayne A. Morgan
  • Patent number: 6400990
    Abstract: A dual-mode telemetry system that allows digital binary data to be efficiently transferred between an implantable device and a patient control unit. The patient control unit utilizes a bidirectional, asymmetric, telemetry link, wherein in a first mode, the patient control unit transmits data at a high bit rate to the implanted device, and in a second mode, the patient control unit receives data at a low bit rate from the implanted device. The telemetry system is relatively simple and inexpensive to construct, and requires minimal modifications to the implanted device.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: June 4, 2002
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 6324428
    Abstract: An implantable cardiac stimulation device having an improved multi-level electronic module is disclosed. The multi-level module comprises at least two stacked internal substrates for mounting electronic components within a confined region formed between the two stacked substrates. Placement of the two stacked substrates creates an opening establishing fluid communication between the confined region and an exterior of the electronic module. A polymer dielectric coating, such as parylene, is vapor deposited over the entire electronic module which penetrates the confined region via the opening. The parylene provides enhanced protection against dielectric breakdown between the electronic components and their interconnections thereby enabling smaller separation distances between the electronic components. The parylene also provides support for the electronic components and their interconnections while acting as a moisture barrier and a particle getter.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: November 27, 2001
    Assignee: Pacesetter, Inc.
    Inventors: Alvin Weinberg, Sergiu Silvian, Min-Yaug Yang
  • Patent number: 6301504
    Abstract: The telemetry system allows a high speed transfer of digital data at for example 81,920 KHz, by utilizing the titanium can as a component of a telemetry link. The telemetry system includes a transmitter and a receiver that are interconnected by means of the telemetry link. Input data is fed to the transmitter where it is encoded, modulated, and transmitted through the can to the receiver. The can introduces a desired low pass filtering function that complements the signal encoding and modulation process implemented by the transmitter. The transmitter processes a binary data signal provided in Non-Return-to-Zero (NRZ) format. By a series of transformations, the transmitter produces a signal whose spectral properties closely match the telemetry link, including the titanium can. The titanium can becomes a source of controlled inter-symbol-interference (ISI) to be compensated for in the receiver.
    Type: Grant
    Filed: October 8, 1999
    Date of Patent: October 9, 2001
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 6096062
    Abstract: An implantable cardiac device incorporating a processor and a waveform generation circuit incorporating a high voltage capacitor wherein the processor is adapted to charge the capacitor to an initial voltage, less than the peak voltage, and then measure the leakage current occurring across the capacitor at the initial voltage. If the leakage current occurring across the capacitor at the initial voltage is less than a preselected value, selected so that the corresponding leakage current across the capacitor when the capacitor is charged to the peak voltage is within an acceptable tolerance range, the processor then does not perform any further reforming of the capacitor.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: August 1, 2000
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 5769876
    Abstract: An improved system is disclosed for telemetering data bidirectionally between two devices such as an implantable device and an external programmer. The two devices both include clock generators that operate at the same nominal frequency, but only one of the devices (i.e., the programmer) includes a phase-locked loop receiver that adjusts the frequency and phase of its clock signal to match that of the received data. The clock generator of the other device (i.e., the implantable device) generates a fixed-phase clock signal, which is selectively inverted or not inverted, to adjust its phase by 180.degree.. This selective 180.degree. adjustment enables the programmer's phase-locked loop receiver to have a reduced, .+-.90.degree. pull-in range, which simplifies its construction and reduces the time required to achieve synchronization.
    Type: Grant
    Filed: July 2, 1996
    Date of Patent: June 23, 1998
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 5700280
    Abstract: The on time of a flyback converter is controlled without the need for a current-sensing resistor. Under one approach, an internal battery resistance R.sub.B is used as a substitute for the current-sensing resistor. The battery voltage V.sub.B decreases as a function of current drain from the battery due to the internal impedance. Charging control circuitry causes the on time to be terminated when the battery voltage V.sub.B falls below a predetermined reference voltage V.sub.R, where V.sub.R =V.sub.B1 -.DELTA..DELTA.V.sub.B. V.sub.B1 represents the battery voltage before charging is commenced, and .DELTA.V.sub.B represents the drop in battery voltage from V.sub.B1 when the battery current drain exceeds a predetermined maximum current. Under another approach, the charging control circuitry regulates the time out period t.sub.on1 =K/V.sub.B, where K is a predetermined constant, such that it is 10-15 percent longer than the on time t.sub.on.
    Type: Grant
    Filed: May 3, 1996
    Date of Patent: December 23, 1997
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 5562713
    Abstract: An improved telemetry system for telemetering data from an implantable device such as a heart pacemaker to an external device with minimum energy consumption. The external device first sweeps its receiver across a predetermined frequency band, e.g., the fm broadcast band of 88 MHz to 108 MHz, to determine the particular frequency having the lowest ambient electromagnetic noise level, which it deems the optimum frequency for the telemetry to occur. The external device's transmitter then commands the pacemaker to telemeter a predetermined start signal at a succession of frequencies that sweep across that same frequency band, while the external device's receiver remains tuned to the optimum frequency. Eventually, the external devices receiver will receive the start signal and the external device thereupon will command the pacemaker to thereafter remain at its current frequency for the subsequent telemetry of data.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: October 8, 1996
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 5475307
    Abstract: An improved digital frequency demodulator and method for demodulating a sampled asynchronous FM input signal that determines the time duration of each successive half cycle by counting the number of successive samples of the same polarity and by interpolating between the samples immediately before and immediately after the detected zero crossings at the beginning and the end of each half cycle.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: December 12, 1995
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 5466246
    Abstract: An improved programmer apparatus for receiving digital data telemetered from an implantable device such as a heart pacemaker with substantially reduced hardware complexity and with convenient flexibility to adapt to data received in multiple modulation formats and data rates. The apparatus includes a conventional front-end receiver for receiving the data in both a reflected-impedance telemetry mode and an active telemetry mode, and it further includes a digital signal processor for efficiently processing data samples of the received telemetry data. Processing the received data in software allows for great processing flexibility, including a convenient reconfiguration to accommodate new modulation formats and data rates for implantable devices developed at a later time.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: November 14, 1995
    Assignee: Pacesetter, Inc.
    Inventor: Sergiu Silvian
  • Patent number: 5350405
    Abstract: A method and apparatus for determining the actual capacitance of a capacitor in a cardiac stimulating device in order to determine the potential necessary to store a desired amount of energy on the capacitor, are provided. The discharge curve of the capacitor is measured during re-forming to determine the time constant of the capacitor and the dumping resistor, and hence the actual capacitance.
    Type: Grant
    Filed: September 16, 1992
    Date of Patent: September 27, 1994
    Assignee: Siemens Pacesetter, Inc.
    Inventor: Sergiu Silvian