Abstract: Battery driven voltage control circuitry charges an output capacitor, which periodically supplies a current pulse. The circuitry converts battery voltage VBAT to a charging voltage VUPC based upon programmed parameters and the voltage VCOMPL at the capacitor. The circuitry includes a voltage converter for multiplying VBAT to produce VUPC. VCOMPL is sampled to determine its “droop” at the end of an output current pulse. If the droop is lower than a threshold, then the voltage converter increases the charging voltage. If the droop is above a threshold, then the voltage converter reduces the charging voltage. This feedback maintains the output voltage within an acceptable operating range to produce an efficacious output current pulse for stimulation without causing unproductive energy loss. In order to avoid premature depletion of battery energy, VUPC is compared with VCOMPL to determine the optimum clock rate to be used to convert VBAT to VUPC.

Abstract: Battery driven voltage control circuitry charges an output capacitor, which periodically supplies a current pulse. The circuitry converts battery voltage VBAT to a charging voltage VUPC based upon programmed parameters and the voltage VCOMPL at the capacitor. The circuitry includes a voltage converter for multiplying VBAT to produce VUPC. VCOMPL is sampled to determine its “droop” at the end of an output current pulse. If the droop is lower than a threshold, then the voltage converter increases the charging voltage. If the droop is above a threshold, then the voltage converter reduces the charging voltage. This feedback maintains the output voltage within an acceptable operating range to produce an efficacious output current pulse for stimulation without causing unproductive energy loss. In order to avoid premature depletion of battery energy, VUPC is compared with VCOMPL to determine the optimum clock rate to be used to convert VBAT to VUPC.

Abstract: A cochlea stimulation system includes a patient wearable system comprising an externally wearable signal processor (WP) and a headpiece in electronic communication with an implanted cochlear stimulator (ICS). The ICS comprises eight output stages each having two electrically isolated capacitor-coupled electrodes, designated "A" and "B", circuits for monitoring the voltages on these electrodes, and circuits for both transmitting status information to and receiving control information from the WP. Based upon information received from the WP, a processor within the ICS can control both the frequency and the widths of the output stimulation pulses applied to the electrodes and may select which electrodes to monitor. The ICS receives power and data signals telemetrically through the skin from the WP. To save power, the ICS may be "powered down" by the WP based upon the absence of audio information or "powered up" if audio is present.

Abstract: An implantable cochlear stimulator (ICS) has eight output stages (212), each having a current source (212B) connected to a pair of electrodes, designated "A" and "B", through respective output coupling capacitors and an electrode switching matrix (212C). An indifferent electrode is connected to each output stage by way of an indifferent electrode switch (212D). The current source generates a precise stimulation current as a function of an analog control voltage. The analog control voltage, in turn, is generated by a logarithmic D/A converter. The D/A converter serially converts data words, received in a data frame from an external source, to respective analog control voltages that are applied sequentially to the current sources of each output stage. An output mode register (208) controls the switching matrix of each stage, as well as the indifferent electrode switch, to configure the electrodes for a desired stimulation configuration, e.g.

Abstract: A method and apparatus for fitting an auditory stimulation system involve, in one embodiment, coupling a programmer unit to an implanted unit implanted in the patient; prompting and/or assisting the operator to make and enter an objective or other measurement; receiving the objective measurements into the programmer unit; and determining an estimated threshold stimulation current for an electrode channel of the implanted unit as a function of the objective measurement. In another embodiment, the method and apparatus involve coupling a programmer unit to an implanted unit implanted in the patient; stimulating the patient with a speech signal; and displaying, in real time, a graphical representation of the speech signal using the programmer unit.

Abstract: An external wearable processor (WP) of a cochlear stimulating system transmits a data signal to an implanted cochlear stimulator (ICS). The ICS is controlled through the data signal so that cochlear stimulation is provided by the ICS only after a determination is made that the WP is in proper signal contact therewith, and that the ICS is functioning properly. The ICS extracts a raw power signal from the data signal and generates different operating voltages from the extracted raw power signal. A detector generates a power bad signal whenever one of the operating voltages is less than a reference voltage. The ICS also detects and generates a carrier detect signal when the data signal is being received. Clock signals are generated within the ICS, and a phase locked loop (PLL) lock signal is generated when the clock signals are phase locked to the data signal. ICS circuitry further checks the parity of the incoming data signal and generates a parity alarm signal whenever a parity error is detected.

Abstract: An implantable cochlear stimulator (ICS) has eight output stages (212), each having a programmable current source (212B) connected to a pair of electrodes, designated "A" and "B", through respective output coupling capacitors and an electrode switching matrix (212C). An indifferent electrode is connected to each output stage by way of an indifferent electrode switch (212D). An output mode register (208) controls the switching matrix of each stage, as well as the indifferent electrode switch, to configure the electrodes for: (1) bipolar stimulation (current flow between the pair of electrodes of the output stage), (2) monopolar A stimulation (current flow between the "A" electrode of the output stage and the indifferent electrode), (3) monopolar B stimulation (current flow between the "B" electrode of the output stage and the indifferent electrode), or (4) multipolar stimulation (current flow between the "A" or "B" electrode of one output stage and the "A" or "B" electrode of another output stage).

Abstract: A tissue stimulating system includes an external transmitter for transmitting a data signal to an implanted stimulator. The implanted stimulator includes a processor for generating stimulation signals for application to a plurality of tissue stimulating electrodes through respective isolated output channels. The implanted stimulator also includes a power supply that extracts a raw power signal from the data signal. A voltage downconverter generates at least four separate voltages from the extracted raw power signal by alternately connecting at least four capacitors in series across the raw power signal, thereby providing at least four output voltages, and then connecting the capacitors in parallel to transfer the charge stored thereon to a storage capacitor, which serves as the power source for portions of the stimulator.