# US 2026/0241184 A1 · Wearable defibrillator with output stage having diverting resistance > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2026/0241184 A1 - Document ID: US20260241184A1 - Status: Published application - Kind: A1 - Application number: 19/641,214 - Filed: 2026-04-07 - Published: 2026-08-20 - Earliest claimed: 2017-11-09 - Assignees: Stryker Corporation - Applicants: Stryker Corporation - Inventors: Kenneth Frederick Cowan; Brian J. Bennett; Joseph L. Sullivan - Web page: https://patentgrep.com/patent/US20260241184A1 ## CPC - A61N 1/3904: {External heart defibrillators [EHD]} - A61N 1/3981: {High voltage charging circuitry} - A61N 1/046: {Specially adapted for shock therapy, e.g. defibrillation} - A61N 1/0484: {Garment electrodes worn by the patient} - A61N 1/3925: {Monitoring; Protecting} - A61N 1/3993: {User interfaces for automatic external defibrillators} - 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) ## Abstract In embodiments, an external defibrillator has an electrical circuit with a special output stage for the high-voltage defibrillation pulse. The output stage includes switches that can turn on for delivering the pulse, and off during all other times. The output stage also includes a diverting resistance to divert electrical current that could leak into the patient while a capacitor is being charged. An optional detector may notify if a component is malfunctioning. An advantage can be that an external defibrillator may be created according to embodiments that uses, in its output stage, semiconductor switches instead of relays. As semiconductor switches weigh less and occupy less volume than relays, an external defibrillator according to embodiments may have less weight and volume. Especially in wearable defibrillator applications, less weight means less effort to carry and less volume means easier concealment under clothing. ## Claims ### Claim 1 A system comprising: a first defibrillator configured to output a first electrical shock; and a second defibrillator comprising: a first node and a second node configured to receive the first electrical shock; a capacitor coupled to a first terminal and to a second terminal and configured to discharge a second electrical shock; a main switch coupled to the first terminal; and an H-bridge circuit comprising: a first branch coupled between the main switch and the first node, the first branch comprising a first switch; a second branch coupled between the main switch and the second node, the second branch comprising a second switch; a third branch coupled between the second terminal and the first node, the third branch comprising a third switch, the first branch or the third branch comprising a first diode configured to block the first electrical shock from being applied to the capacitor; and a fourth branch coupled between the second terminal and the second node, the fourth branch comprising a fourth switch, the second branch or the fourth branch comprising a second diode configured to block the first electrical shock from being applied to the capacitor. ### Claim 2 (depends on 1) The system of claim 1, wherein the first diode and the second diode are reverse biased during a first time, and wherein the first diode and the second diode are forward biased during a second time, the capacitor being configured to discharge the second electrical shock during the second time. ### Claim 3 (depends on 1) The system of claim 1, wherein a breakdown voltage of the first diode or the second diode is greater than or equal to a voltage of the first electrical shock. ### Claim 4 (depends on 1) The system of claim 1, wherein the first branch comprises the first diode; wherein the second branch comprises the second diode; wherein the third branch further comprises a third diode; and wherein the fourth branch further comprises a fourth diode. ### Claim 5 (depends on 1) The system of claim 1, wherein the first node is configured to be coupled to a first defibrillation electrode, wherein the second node is configured to be coupled to a second defibrillation electrode, wherein the first defibrillation electrode and the second defibrillation electrode are configured to be disposed on a subject; and wherein the first defibrillator is configured to output the first electrical shock to the subject. ### Claim 6 (depends on 1) The system of claim 1, wherein a first resistor is coupled between an intermediate terminal of the first branch and a reference node, the intermediate terminal of the first branch being between the first switch and the first diode, the reference node being configured to receive a constant reference voltage, and wherein a second resistor is coupled between the reference node and an intermediate terminal of the second branch, the intermediate terminal of the second branch being between the second switch and the second diode. ### Claim 7 (depends on 1) The system of claim 1, wherein the second defibrillator further comprises: a driver circuit electrically connected to the first switch, the driver circuit comprising a power source, a boost capacitor configured to output a boost voltage, and a control switch, wherein the control switch is configured to: open in response to the first electrical shock, thereby disconnecting the power source from the boost capacitor; and connect the power source to the boost capacitor by closing. ### Claim 8 A medical device comprising: a first electrode and a second electrode configured to be disposed on a subject; a first node configured to be coupled to the first electrode; a second node configured to be coupled to the second electrode; a capacitor coupled to a first terminal and to a second terminal and configured to output an electrical shock; a main switch coupled to the first terminal; and an H-bridge comprising: a first branch coupled between the main switch and the first node, the first branch comprising a first switch; a second branch coupled between the main switch and the second node, the second branch comprising a second switch; a third branch coupled between the second terminal and the first node, the third branch comprising a third switch, the first branch or the third branch comprising a first diode; and a fourth branch coupled between the second terminal and the second node, the fourth branch comprising a fourth switch, the second branch or the fourth branch comprising a second diode. ### Claim 9 (depends on 8) The medical device of claim 8, wherein the first diode is configured to block current flow from the first node to the capacitor, and the second diode is configured to block current flow from the second node to the capacitor. ### Claim 10 (depends on 8) The medical device of claim 8, wherein the first diode and the second diode are forward biased during a first time, the capacitor being configured to output the electrical shock during the first time, and wherein the first diode and the second diode are reverse biased during a second time. ### Claim 11 (depends on 8) The medical device of claim 8, wherein the first diode or the second diode comprise a Zener diode, an insulated-gate bipolar transistor (IGBT), or a metal-oxide-semiconductor field-effect transistors (MOSFET). ### Claim 12 (depends on 8) The medical device of claim 8, wherein the first branch comprises the first diode, and wherein the second branch comprises the second diode, the medical device further comprising: a third diode, the third branch comprising the third diode; and a fourth diode, the fourth branch comprising the fourth diode. ### Claim 13 (depends on 12) The medical device of claim 12, wherein a capacitance of the first diode is less than a capacitance of the second switch, and wherein a capacitance of the second diode is less than a capacitance of the first switch. ### Claim 14 (depends on 12) The medical device of claim 12, wherein a first resistor is coupled between an intermediate terminal of the third branch and a first reference node, the intermediate terminal of the third branch being between the third switch and the third diode, the first reference node being configured to receive a first constant reference voltage, and wherein a second resistor is coupled between an intermediate terminal of the fourth branch and a second reference node, the intermediate terminal of the fourth branch being between the fourth switch and the fourth diode, the second reference node being configured to receive a second constant reference voltage. ### Claim 15 (depends on 12) The medical device of claim 12, wherein a first resistor is coupled between an intermediate terminal of the first branch and a reference node, the intermediate terminal of the first branch being between the first switch and the first diode, the reference node being configured to receive a constant reference voltage, and wherein a second resistor is coupled between the reference node and an intermediate terminal of the second branch, the intermediate terminal of the second branch being between the second switch and the second diode. ### Claim 16 A method comprising: receiving, at a first node and a second node of a second defibrillator from a first defibrillator, an electrical shock; and blocking, by a first diode and a second diode in an H-bridge of the second defibrillator, a current corresponding to the electrical shock from being applied to a capacitor of the second defibrillator. ### Claim 17 (depends on 16) The method of claim 16, the electrical shock being a first electrical shock, the method further comprising: outputting, by discharging the capacitor to the first node and the second node of the second defibrillator, a second electrical shock. ### Claim 18 (depends on 17) The method of claim 17, wherein the first diode and the second diode are reverse biased during a first time, the first electrical shock being received during the first time, and wherein the first diode and the second diode are forward biased during a second time, the second electrical shock being output during the second time. ### Claim 19 (depends on 17) The method of claim 17, wherein the H-bridge comprises: a first branch coupled between the first node and a main switch, the first branch comprising a first switch; and a second branch coupled between the second node and the main switch, wherein the first switch is coupled to a driver circuit comprising a power source, a boost capacitor configured to output a boost voltage, and a control switch, the method further comprising: in response to receiving the first electrical shock, opening the control switch, thereby disconnecting the power source from the boost capacitor. ### Claim 20 (depends on 19) The method of claim 19, wherein outputting the second electrical shock comprises closing the control switch.