Digital-to-Analog (DAC) circuitry for an implantable pulse generator is disclosed which is used to program currents at the electrodes. Calibration circuitry allows the positive and negative currents produced at each electrode to be independently calibrated to achieve an ideal (linear) response across a range of amplitude values provided to the DAC circuitry by a digital amplitude bus. The calibration circuitry includes electrode gain and electrode offset circuitry for each of the electrodes. Current range DAC circuitry is also provided which can be used to adjust the gain and offset current at all of the electrodes. The current range DAC circuitry is particularly useful when spanning a range of therapeutic currents for a patient, and allows all possible amplitude values provided by the digital bus to be used to span the range. This can improve (reduce) the current resolution of the electrode currents with each amplitude value step.

The types of electrode leads that are connected to an implantable medical device are determined based on electrical parameters that are measured at the electrodes that are positioned on the leads. The different types of known electrode leads have different physical electrode arrangements that impact the measured electrical parameters. Properties in the measured electrical parameters that are indicative of the physical arrangements of electrodes of known types of electrode leads are utilized to determine the types of leads that are connected to the implantable medical device.

The disclosure describes an implementation of a combinational thermometric-R2R that includes a thermometric DAC circuit to output the coarse output steps, an R2R circuit to control the fine output steps, and a resistor in series with the thermometric and R2R circuits. The techniques of this disclosure implement a fine resolution DAC, on the order of two nanoamps per bit, that operates at low current, yet maintains monotonicity throughout the DAC output range.

In some embodiments, a method of providing a neurostimulation therapy to a patient, comprises: generating electrical pulses, by an implantable pulse generator (IPG), comprising respective bursts of a plurality of anodic pulses with each anodic pulse being separated by a time gap, wherein (1) the plurality of anodic pulses comprise successively increasing charge; (2) the plurality of anodic pulses are charge limited to be sub-threshold; (3) each burst of anodic pulses is followed by a discharge phase of intermittent time periods to discharge charge build up from the anodic pulses; and (4) each successive intermittent time period increases in time through the discharge phase to avoid action potential (AP) generation; and applying the generated electrical pulses to neural tissue of the patient to inhibit neural activity of the patient.

An implantable neurostimulator system including an electrical lead having formed thereon a pair of bipolar electrodes, the electrical lead is configured for placement of the pair of bipolar electrodes proximate protrusor muscles of a patient. The system also includes a pulse generator electrically connected to the electrical lead and configured to deliver electrical energy to the pair of bipolar electrodes, the pulse generator having mounted therein a sensor configured to detect one or more physiological parameters, a memory, a control circuit, and a telemetry circuit. The system also including a communications telemetry module (CTM) in communication with the telemetry circuit and configured to receive a data collected by the sensor and data related to delivery of electrical energy to the bipolar electrodes, and an external programmer in communication with the CTM and configured to display a user interface the data collected by the sensor and data related to delivery of electrical energy to the bipolar electrodes.

An implantable pulse generator (IPG) is disclosed having a plurality of electrode nodes, each electrode node configured to be coupled to an electrode to provide stimulation pulses to a patient's tissue. The IPG includes a digital-to-analog converter configured to amplify a reference current to a first current specified by first control signals; a first resistance configured to receive the first current, wherein a voltage across the first resistance is held to a reference voltage at a first node; a plurality of branches each comprising a second resistance and configured to produce a branch current, wherein a voltage across each second resistance is held to the reference voltage at second nodes; and a switch matrix configurable to selectively couple any branch current to any of the electrode nodes via the second nodes.

Passive tissue biasing circuitry in an Implantable Pulse Generator (IPG) is disclosed to facilitate the sensing of neural responses by holding the voltage of the tissue to a common mode voltage (Vcm). The IPG's conductive case electrode, or any other electrode, is passively biased to Vcm using a capacitor, as opposed to actively driving the (case) electrode to a prescribed voltage using a voltage source. Once Vcm is established, voltages accompanying the production of stimulation pulses will be referenced to Vcm, which eases neural response sensing. An amplifier can be used to set a virtual reference voltage and to limit the amount of current that flows to the case during the production of Vcm. In other examples, circuitry can be used to monitor the virtual reference voltage as useful to enabling the sensing the neural responses, and as useful to setting a compliance voltage for the current generation circuitry.

The present invention concerns an optoelectronic stimulating device for use in a medical treatment involving delivering an electrical current to an electrically excitable tissue (Z.sub.bio) by means of two electrodes (3n, 3p) electrically coupled to said tissue, said optoelectronic stimulating device comprising: (a) a source (4) of electrical impulses, which is electrically connected to (b) a source of light emission (2), in optical communication with (c) a photovoltaic cell (1) electrically connected to two electrodes (3n, 3p) for establishing two electrical contacts with said tissue and thus forming an electrical stimulating circuit fed by the photovoltaic cell (1) which is energized by the radiation of the source of light emission (2).

An output signal driver includes a positive output node, a negative output node, a power supply input node, a power supply common node, a charging capacitor, a discharging capacitor, a current source, a current sink, a first switch, a second switch, and a controller. The charging capacitor is coupled to the power supply input node. The discharging capacitor is coupled to the negative output node. The current source is coupled between the power supply input node and the positive output node. The current sink is coupled between the positive output node and the power supply common node. The first switch is coupled in parallel with the current source. The second switch is coupled in parallel with the current sink. The controller is coupled to the current source, the current sink, the first switch, and the second switch to apply either complementary constant current pulses or complementary constant voltage pulses to the positive output node.

A current stimulator includes a first current generation circuit configured to generate a first current, injectable into a cranial nerve cell, through a current mirroring based on a plurality of transistor pairs; and a second current generation circuit, driven by a clock, configured to generate a second current smaller than the first current by controlling a charge rate based on a voltage difference between terminals of a capacitor. A first output impedance of the first current generation circuit and a second output impedance of the second current generation circuit have a magnitude greater than or equal to a predetermined ratio to a load impedance corresponding to the cranial nerve cell.