Abstract: An implantable pump includes a base plate and a can that are parts of the pump housing. The base plate bottom divides the housing into a first electronics chamber and a second chamber. A bellows mechanism is connected to the base plate and is disposed within the second chamber. The bellow mechanism has an expandable sidewall and a bottom plate. The bellow mechanism divides the second chamber into a medicament receiving portion and a non-medicament-receiving portion. The bellow mechanism has an intermediate plate disposed within the medicament-receiving portion. A coil is disposed in a recess on the lower surface of the base plate, and the coil is spaced from an internal wall of the recess. The amount of fluid remaining in the implantable pump can be monitored by energizing the coil. A primary magnetic field is generated by the energized coil.

Abstract: An implantable pump includes a base plate and a can that are parts of the pump housing. The base plate bottom divides the housing into a first electronics chamber and a second chamber. A bellows mechanism is connected to the base plate and is disposed within the second chamber. The bellow mechanism has an expandable sidewall and a bottom plate. The bellow mechanism divides the second chamber into a medicament receiving portion and a non-medicament-receiving portion. The bellow mechanism has an intermediate plate disposed within the medicament-receiving portion. A coil is disposed in a recess on the lower surface of the base plate, and the coil is spaced from an internal wall of the recess. The amount of fluid remaining in the implantable pump can be monitored by energizing the coil. A primary magnetic field is generated by the energized coil.

Abstract: An implant includes a processor, RF communication circuitry, optical communication circuitry, a power source and a memory, all of which being hermetically sealed within a housing having a transparent window. Sensor readings are transmitted by RF using the RF communication circuitry to a remote reader after receiving interrogation signals from the reader. During calibration of the sensor, corrective coefficients are calculated by comparing actual sensor pressure readings with known pressure readings. The corrective coefficients are transmitted to the memory of the control circuitry using optical communication wherein modulated light is transmitted through the transparent window of the housing to the photo-detector.

Abstract: Circuitry for automatically powering on and maintaining activation of a powered down electronic component in a first device in RF communication with a second device, wherein the first and second devices are preferably an implantable medical device and an external control device, respectively. The system including power logic circuitry for generating a power on signal to automatically close a switch and energize an otherwise powered off electronic device when the power induced in the first device by external RF energy transmitted in the RF communication signal exceeds a minimum operating threshold of the power on logic circuitry. The electronic component while powered by the power source generates a hold signal and a second power signal that is transmitted to the power on logic circuitry to sustain power to the electronic component irrespective of interruptions of relatively short duration for less than a predetermined period of time in RF communication.

Abstract: A wireless communication system with power regulation feedback for improving the robustness of wireless communication transmissions between a receiver and an active emitter irrespective of the distance separation therebetween. The receiver receives wireless communications and detects a voltage induced therein. A feedback loop provides wireless transmission of power regulation feedback based on the detected voltage. The active emitter generates a power regulated data signal in which at least one of maximum and minimum bit voltage levels of respective logical high and low bits is adjusted based on the induced voltage received via the feedback loop. The RF power level, modulation index, and/or slew rate of a data signal emitted from the active emitter is regulated by adjusting at least one of maximum and minimum bit voltage levels of respective logical high and low bits based on voltage induced in the receiver during a previous communication from the active emitter.

Abstract: Methods and devices are described for monitoring reservoir fluid in an implantable infusion pump. Such methods and devices can be used when the infusion pump has a temperature-dependent component. For example, a method of monitoring reservoir fluid can include obtaining measurements from the reservoir that include corresponding data related to the amount of fluid and temperature in the reservoir. A pair of measurements can be used to monitor the fluid level, or flow rate out of, the reservoir when the corresponding temperatures of the measurements are within a temperature tolerance value. In such an instance, a measured amount difference can be calculated based on the fluid amounts corresponding to the pair of measurements. Other variations of fluid monitoring methods, and implantable infusion pump systems that can perform fluid monitoring, are also described.

Abstract: Optimal power switching circuitry for use in a closed system such as a TET system including an internal device separated from an external device by a boundary. The internal and external devices being powered by separate power sources. During telemetric communication from the external device to the internal device an external RF energy source is produced. If the power supplied by the external RF energy source produced during communication from the external device to the internal device exceeds that required for powering of the internal device, then the power switching circuitry cuts off power to the internal power source and instead draws power from the external RF energy source thereby conserving power consumed from the internal power source. The power switching circuitry may be implemented using either passive components (e.g., diodes) or active components (e.g., an analog switch).

Abstract: An implantable medical device includes a hermetically sealed housing that contains electronic circuitry. A feedthrough is disposed on an external surface of the housing. An antenna wire is disposed around the external surface of the housing. The antenna wire has one end connected to the feedthrough so that the antenna wire is in electric communication with at least a portion of the electronic circuitry. A heat shrink tube is sealingly disposed about substantially the entire external surface of the antenna wire to prevent fluids from contacting the antenna wire and thereby detuning the antenna wire. An antenna surround is disposed about the tube.

Abstract: A system and method for restricting proper regulation by a control unit of only the functionality of the targeted device whose operations are intended to be programmed so as to insure no adverse regulation of functionality with respect to any other non-targeted device. A memory associated with each of the control device and the targeted device stores a unique identification assigned to that targeted device compressed using an error detection scheme, wherein the compressed unique identification has a length less than or equal to that of each of the messages. Circuitry, such as a logic function, mixes the stored compressed unique identification with each message transmitted between the two devices subsequent to receipt of a response signal from the targeted device to an interrogation command from the control device to insure proper communication between the control device and the targeted device.

Abstract: A telemetry system including a first device having a processor that employs a DC balanced encoding scheme to generate a DC balanced encoded data signal, a modulator for modulating an RF carrier wave by the DC balanced encoded data signal and generating a DC balanced encoded RF modulated data signal including DC balanced RF energy. The DC balanced encoded RF modulated data signal transmitted by the first device is received by a second device. Since the RF energy received is DC balanced, drift in baseline voltage is eliminated irrespective of data transmission thereby improving the robustness of recovery of data by the second device. The second device may include a converter for converting the DC balanced RF energy extracted from the received DC balanced encoded RF modulated data signal to a substantially constant average induced voltage, irrespective of data being transmitted, for powering at least one component of the second device.

Abstract: A wireless communication system with power regulation feedback for improving the robustness of wireless communication transmissions between a receiver and an active emitter irrespective of the distance separation therebetween. The receiver receives wireless communications and detects a voltage induced therein. A feedback loop provides wireless transmission of power regulation feedback based on the detected voltage. The active emitter generates a power regulated data signal in which at least one of maximum and minimum bit voltage levels of respective logical high and low bits is adjusted based on the induced voltage received via the feedback loop. The RF power level, modulation index, and/or slew rate of a data signal emitted from the active emitter is regulated by adjusting at least one of maximum and minimum bit voltage levels of respective logical high and low bits based on voltage induced in the receiver during a previous communication from the active emitter.

Abstract: Optimal power switching circuitry for use in a closed system such as a TET system including an internal device separated from an external device by a boundary. The internal and external devices being powered by separate power sources. During telemetric communication from the external device to the internal device an external RF energy source is produced. If the power supplied by the external RF energy source produced during communication from the external device to the internal device exceeds that required for powering of the internal device, then the power switching circuitry cuts off power to the internal power source and instead draws power from the external RF energy source thereby conserving power consumed from the internal power source. The power switching circuitry may be implemented using either passive components (e.g., diodes) or active components (e.g., an analog switch).

Abstract: A system and method for establishing communication among a control device and an implantable medical device. The implantable medical device transmits to the control device identification information including a unique identification number associated with the implantable medical device and/or a current version of application software currently being utilized by the implantable medical device. Based on the extracted identification information, the control device correlates thereto a version of the application software from among the multiple versions of application software associated with the control device that is compatible with the recognized version of the application software currently being utilized by the implantable medical device.

Abstract: Improving the accuracy of the flow rate of a valve in a fluidic delivery device in which a desired flow rate may be achieved by varying the duty cycle of the valve. The flow rate of fluid delivery from the valve over its lifetime is stabilized by minimizing the voltage OPENING time of the valve to account for valve and piezoelectric actuator drift. Also, the valve OPENING time of one or more fluidic parameters that impact on the flow rate delivery by the valve and differ among fluidic delivery devices is compensated to optimize the flow rate accuracy.

Abstract: Improving the accuracy of the flow rate of a valve in a fluidic delivery device in which a desired flow rate may be achieved by varying the duty cycle of the valve. The flow rate of fluid delivery from the valve over its lifetime is stabilized by minimizing the voltage OPENING time of the valve to account for valve and piezoelectric actuator drift. Also, the valve OPENING time of one or more fluidic parameters that impact on the flow rate delivery by the valve and differ among fluidic delivery devices is compensated to optimize the flow rate accuracy.

Abstract: Circuitry for conserving power in a system employing multiple electronic components of which a first electronic component operates at a first frequency and is continuously powered on by a power source. The system further includes a second electronic component operating at a second frequency different than that of the first frequency of the first electric component, the second electronic component being maintained in a powered off state in which no energy whatsoever is consumed by the second electronic component until energized in response to a power enabling signal generated by the first electronic component based on demand of the particular function to be performed by the second electronic component. The first and second electronic components may be processors, wherein the frequency of the first processor is lower than that of the second processor.

Abstract: A wireless communication system with power regulation feedback for improving the robustness of wireless communication transmissions between a receiver and an active emitter irrespective of the distance separation therebetween. The receiver receives wireless communications and detects a voltage induced therein. A feedback loop provides wireless transmission of power regulation feedback based on the detected voltage. The active emitter generates a power regulated data signal in which at least one of maximum and minimum bit voltage levels of respective logical high and low bits is adjusted based on the induced voltage received via the feedback loop. The RF power level, modulation index, and/or slew rate of a data signal emitted from the active emitter is regulated by adjusting at least one of maximum and minimum bit voltage levels of respective logical high and low bits based on voltage induced in the receiver during a previous communication from the active emitter.

Abstract: A remotely controlled gastric band system that is practically immune to external magnetic fields, such as from a Magnetic Resonance Imaging (MRI) machine, incorporates a bi-directional pump and fluid reservoir to adjust fluid volume for hydraulic control of a gastric band. A piezoelectric driver (e.g., rotary actuator, linear actuator) selectively compresses and expands a metal bellows hermetically sealed within a biocompatible and nonferromagnetic enclosure or case such as titanium. Directly sensing a position of the metal bellows yields an accurate reading of volume contained therein, allowing for closed-loop control of the gastric band.

Abstract: Circuitry for conserving power in a system employing multiple electronic components of which a first electronic component operates at a first frequency and is continuously powered on by a power source. The system further includes a second electronic component operating at a second frequency different than that of the first frequency of the first electric component, the second electronic component being maintained in a powered off state in which no energy whatsoever is consumed by the second electronic component until energized in response to a power enabling signal generated by the first electronic component based on demand of the particular function to be performed by the second electronic component. The first and second electronic components may be processors, wherein the frequency of the first processor is lower than that of the second processor.

Abstract: Continuous phase frequency shift keying modulation is employed during wireless transmission from an internal device to an external device to increase robustness of transmissions. The continuous phase frequency shift keying processor receives as input an incoming data stream and includes a timer for toggling its output between a first predetermined frequency and a second predetermined frequency on a predetermined time period basis based on the logical state of each bit in the incoming data stream. For a portion of time while the counter or timer of the CPFSK processor is counting down the predetermined time period associated with the detected logic state of a particular bit of the incoming data signal at least some of the other circuitry, preferably all of the other circuitry of the processor, is toggled to a sleep mode in which power is cut off thereby minimizing power consumption by the processor during this interim state.