# US 12,377,273 B2 · Circuitry to assist with neural sensing in an implantable stimulator device in the presence of stimulation artifacts > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,377,273 B2 - Document ID: US12377273B2 - Status: Granted - Kind: B2 - Application number: 18/060,344 - Filed: 2022-11-30 - Published: 2023-06-08 - Granted: 2025-08-05 - Earliest claimed: 2021-12-02 - Assignees: Boston Scientific Neuromodulation Corporation - Applicants: Boston Scientific Neuromodulation Corporation - Inventors: Pujitha Weerakoon; Goran N. Marnfeldt - Web page: https://patentgrep.com/patent/US12377273B2 ## CPC - A61N 1/08: Arrangements or circuits for monitoring, protecting, controlling or indicating {(for external stimulators A61N1/3603; for implantable neurostimulators A61N1/36128; for heart stimulators A61N1/37; for defibrillators A61N1/3925)} - A61N 1/36125: {Details of circuitry or electric components} - A61B 5/30: Input circuits therefor - A61B 5/4836: {Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence)} - A61B 5/7203: {for noise prevention, reduction or removal} - A61B 5/7225: {Details of analogue processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation (input circuits for detecting, measuring, or recording bioelectric or biomagnetic signals A61B5/30; specific diagnostic methods using bioelectric or biomagnetic signals A61B5/316)} - A61N 1/36135: {using physiological parameters} - A61N 1/3782: {producing a voltage above the power source level} - H03F 3/45264: {Complementary cross coupled types} - A61B 5/287: Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS] - A61B 5/293: Invasive - A61B 5/294: for nerve conduction study [NCS] - A61N 1/36062: {Spinal stimulation} - A61N 1/36142: {for improving safety} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - H03F: AMPLIFIERS ## Abstract Sense amplifier (amp) circuitry for an implantable stimulator device is disclosed useful for sensing neural responses or other voltages in a patient's tissue. The sense amp circuitry comprises a low-voltage and a high-voltage sense amp circuit, either of which may be selected based on an assessment of the magnitude of the voltage at either or both of the inputs connected to selected sensing electrodes. The assessed magnitude, as determined by monitoring circuitry, can be processed by an algorithm to select use of one of the sense amp circuits, selecting the low-voltage sense amp circuit when the magnitude(s) are lower, and the high-voltage sense amp circuit when the magnitude(s) are higher. Furthermore, DC offset compensation circuitry is disclosed to equate the DC levels of the inputs, which may only operate when the high-voltage sense amp is selected. ## Claims ### Claim 1 A stimulator device, comprising: a plurality of electrode nodes, wherein each of the electrode nodes is associated with a different electrode configured to contact a patient's tissue, wherein at least one of the electrodes comprises a sensing electrode to receive a voltage from the tissue, wherein each electrode node associated with the at least one sensing electrode comprises a sensing electrode node; sense amplifier circuitry comprising a first amplifier with a first input and a first output and a second amplifier with a second input and a second output; and monitoring circuitry configured to assess a voltage at each sensing electrode node, wherein the monitoring circuitry is configured based on the assessed one or more voltages to select use of the first or the second amplifier to determine a signal in the tissue. ### Claim 2 (depends on 1) The stimulator device of claim 1, further comprising input switching circuitry between each sensing electrode node and the first input and between each sensing electrode node and the second input, wherein the monitoring circuitry is configured to select the first or the second amplifier by controlling the input switching circuitry to either connect each sensing electrode node to the first input or to the second input. ### Claim 3 (depends on 2) The stimulator device of claim 2, further comprising an analog-to-digital converter (ADC), wherein the ADC is configured to provide a digitized representation of the determined signal; and output switching circuitry between the first output and the ADC and between the second output and the ADC, wherein the monitoring circuitry is configured to select the first or the second amplifier by controlling the output switching circuitry to either couple the first output to communicate with the ADC or to couple the first output to communicate with the ADC. ### Claim 4 (depends on 1) The stimulator device of claim 1, further comprising processing circuitry, wherein the coupled first or second output communicates with the ADC via the processing circuitry. ### Claim 5 (depends on 4) The stimulator circuitry of claim 4, wherein the processing circuitry comprises one or more of an additional amplifier to impart a gain to the first or second output of the selected first or second amplifier, and filter circuitry to filter the first or second output of the selected first or second amplifier. ### Claim 6 (depends on 1) The stimulator device of claim 1, wherein the first amplifier is powered by a first power supply voltage, and wherein the second amplifier is powered by a second power supply voltage higher than the first power supply voltage. ### Claim 7 (depends on 6) The stimulator device of claim 6, further comprising stimulation circuitry configured to provide stimulation to one or more of the electrode nodes to provide stimulation to the patient's tissue via associated stimulation electrodes. ### Claim 8 (depends on 7) The stimulator device of claim 7, wherein the stimulation electrodes are different from the at least one sensing electrode. ### Claim 9 (depends on 7) The stimulator device of claim 7, wherein the stimulation circuitry is powered by the second power supply voltage. ### Claim 10 (depends on 1) The stimulator device of claim 1, wherein the monitoring circuitry is configured to assess the voltage at each sensing electrode node by comparing the voltage at each sensing electrode node to a first voltage. ### Claim 11 (depends on 10) The stimulator device of claim 10, wherein the monitoring circuitry is configured to select the first amplifier if the voltage at each sensing electrode node is below the first voltage. ### Claim 12 (depends on 10) The stimulator device of claim 10, wherein the monitoring circuitry is configured to select the second amplifier if the voltage at any sensing electrode node is above the first voltage. ### Claim 13 (depends on 10) The stimulator device of claim 10, wherein the first amplifier is powered by a first power supply voltage, wherein the first voltage is set relative to the first power supply voltage. ### Claim 14 (depends on 13) The stimulator device of claim 13, wherein the first voltage equals the first power supply voltage. ### Claim 15 (depends on 1) The stimulator device of claim 1, wherein the monitoring circuitry is further configured upon the occurrence of an initialization event to select the use of the first amplifier during an initialization period. ### Claim 16 (depends on 1) The stimulator device of claim 1, wherein the monitoring circuitry comprises an algorithm to assess the voltage at each sensing electrode node, wherein the algorithm is configured to generate a control signal based on the assessed voltages to select the use of the first or the second amplifier. ### Claim 17 (depends on 1) The stimulator device of claim 1, further comprising a DC-blocking capacitance between each of the electrode nodes and its associated electrode. ### Claim 18 (depends on 1) The stimulator device of claim 1, wherein the first amplifier and the second amplifier comprise differential amplifiers, wherein the first input comprises a first differential input, and wherein the second input comprises a second differential input. ### Claim 19 (depends on 18) The stimulator device of claim 18, wherein two of the electrodes comprise the sensing electrodes to receive the voltage from the tissue, wherein two sensing electrode nodes are associated with the two sensing electrodes, wherein the monitoring circuitry is configured to assess the voltages at the two sensing electrode nodes, wherein the monitoring circuitry is configured based on the assessed voltages to select the use of the first or the second amplifier by respectively connecting the two sensing electrode nodes to the first differential input or the second differential input. ### Claim 20 (depends on 18) The stimulator device of claim 18, wherein only one of the electrodes comprises the sensing electrode to receive the voltage from the tissue, wherein one sensing electrode node is associated with the sensing electrode, wherein the monitoring circuitry is configured to assess the voltage at the one sensing electrode node, wherein the monitoring circuitry is configured based on the assessed voltage to select the use of the first or the second amplifier by respectively connecting the sensing electrode node to the first differential input or the second differential input, wherein the sensing electrode node is compared to a reference voltage of the selected first or second amplifier.