Abstract:
An AIMD includes a conductive housing, an electrically conductive ferrule with an insulator hermetically sealing the ferrule opening. A conductive pathway is hermetically sealed and disposed through the insulator. A filter capacitor is disposed on a circuit board within the housing and has a dielectric body supporting at least two active and two ground electrode plates interleaved, wherein the at least two active electrode plates are electrically connected to the conductive pathway on the device side, and the at least two ground electrode plates are electrically coupled to either the ferrule and/or the conductive housing. The dielectric body has a dielectric constant less than 1000 and a capacitance of between 10 and 20,000 picofarads. The filter capacitor is configured for EMI filtering of MRI high RF pulsed power by a low ESR, wherein the ESR of the filter capacitor at an MRI RF pulsed frequency or range of frequencies is less than 2.0 ohms.
Abstract:
An AIMD includes a conductive housing, an electrically conductive ferrule with an insulator hermetically sealing the ferrule opening. A conductive pathway is hermetically sealed and disposed through the insulator. A filter capacitor is disposed on a circuit board within the housing and has a dielectric body supporting at least two active and two ground electrode plates interleaved, wherein the at least two active electrode plates are electrically connected to the conductive pathway on the device side, and the at least two ground electrode plates are electrically coupled to either the ferrule and/or the conductive housing. The dielectric body has a dielectric constant less than 1000 and a capacitance of between 10 and 20,000 picofarads. The filter capacitor is configured for EMI filtering of MRI high RF pulsed power by a low ESR, wherein the ESR of the filter capacitor at an MRI RF pulsed frequency or range of frequencies is less than 2.0 ohms.
Abstract:
A shielded component or network for an active medical device (AMD) implantable lead includes (1) an implantable lead having a length extending from a proximal end to a distal end, all external of an AMD housing, (2) a passive component or network disposed somewhere along the length of the implantable lead, the passive component or network including at least one inductive component having a first inductive value, and (3) an electromagnetic shield substantially surrounding the inductive component or the passive network. The first inductive value of the inductive component is adjusted to a account for a shift in its inductance to a second inductive value when shielded.
Abstract:
An AIMD includes a conductive housing, an electrically conductive ferrule with an insulator hermetically sealing the ferrule opening. A conductive pathway is hermetically sealed and disposed through the insulator. A filter capacitor is disposed within the housing and has a dielectric body supporting at least two active and two ground electrode plates interleaved, wherein the at least two active electrode plates are electrically connected to the conductive pathway on the device side, and the at least two ground electrode plates are electrically coupled to either the ferrule and/or the conductive housing. The dielectric body has a dielectric constant less than 1000 and a capacitance of between 10 and 20,000 picofarads. The filter capacitor is configured for EMI filtering of MRI high RF pulsed power by a low ESR, wherein the ESR of the filter capacitor at an MRI RF pulsed frequency or range of frequencies is less than 2.0 ohms.
Abstract:
An AIMD includes a conductive housing, an electrically conductive ferrule with an insulator hermetically sealing the ferrule opening. A conductive pathway is hermetically sealed and disposed through the insulator. A filter capacitor is disposed within the housing and has a dielectric body supporting at least two active and two ground electrode plates interleaved, wherein the at least two active electrode plates are electrically connected to the conductive pathway on the device side, and the at least two ground electrode plates are electrically coupled to either the ferrule and/or the conductive housing. The dielectric body has a dielectric constant less than 1000 and a capacitance of between 10 and 20,000 picofarads. The filter capacitor is configured for EMI filtering of MRI high RF pulsed power by a low ESR, wherein the ESR of the filter capacitor at an MRI RF pulsed frequency or range of frequencies is less than 2.0 ohms.
Abstract:
A composite RF current attenuator for a medical lead includes a conductor having a distal electrode contactable to biological cells, a bandstop filter in series with the lead conductor for attenuating RF currents flow through the lead conductor at a selected center frequency or across a range of frequencies about the center frequency, and a lowpass filter in series with the bandstop filter and forming a portion of the lead conductor. The bandstop filter has a capacitance in parallel with a first inductance. In a preferred form, the lowpass filter includes a second inductance in series with the bandstop filter, wherein the values of capacitance and inductances for the composite RF current attenuator are selected such that it attenuates MRI-induced RF current flow in an MRI environment.
Abstract:
A shielded component or network for an active medical device (AMD) implantable lead includes an implantable lead having a length extending from a proximal end to a distal end, all external of an AMD housing, a passive component or network disposed somewhere along the length of the implantable lead, the passive component or network including at least one inductive component having a first inductive value, and an electromagnetic shield substantially surrounding the inductive component or the passive network. The first inductive value of the inductive component is adjusted to account for a shift in its inductance to a second inductive value when shielded.
Abstract:
A shielded component or network for an active medical device (AMD) implantable lead includes (1) an implantable lead having a length extending from a proximal end to a distal end, all external of an AMD housing, (2) a passive component or network disposed somewhere along the length of the implantable lead, the passive component or network including at least one inductive component having a first inductive value, and (3) an electromagnetic shield substantially surrounding the inductive component or the passive network. The first inductive value of the inductive component is adjusted to a account for a shift in its inductance to a second inductive value when shielded.
Abstract:
A miniature electrochemical cell having a total volume that is less than 0.5 cc is described. The cell casing is formed by joining two ceramic casing halves together. One or both casing halves are machined from ceramic to provide a recess that is sized and shaped to contain the electrode assembly. The opposite polarity terminals are electrically conductive feedthroughs or pathways, such as of gold, and are formed by brazing gold into tapered via holes machined into one or both ceramic casing halves. The two ceramic casing halves are separated from each other by a metal interlayer, such as of gold, bonded to a thin film metallization layer, such as of titanium, that contacts an edge periphery of each ceramic casing half. A solid electrolyte of LiPON (LixPOyNz) is used to activate the electrode assembly.
Abstract:
An AIMD includes a conductive housing, an electrically conductive ferrule with an insulator hermetically sealing the ferrule opening. A conductive pathway is hermetically sealed and disposed through the insulator. A filter capacitor is disposed on a circuit board within the housing and has a dielectric body supporting at least two active and two ground electrode plates interleaved, wherein the at least two active electrode plates are electrically connected to the conductive pathway on the device side, and the at least two ground electrode plates are electrically coupled to either the ferrule and/or the conductive housing. The dielectric body has a dielectric constant less than 1000 and a capacitance of between 10 and 20,000 picofarads. The filter capacitor is configured for EMI filtering of MRI high RF pulsed power by a low ESR, wherein the ESR of the filter capacitor at an MRI RF pulsed frequency or range of frequencies is less than 2.0 ohms.