# US 2017/0288545 A1 · Circuit device, switching regulator, and electronic > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0288545 A1 - Document ID: US20170288545A1 - Status: Published application - Kind: A1 - Application number: 15/458,165 - Filed: 2017-03-14 - Published: 2017-10-05 - Earliest claimed: 2016-03-30 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Atsushi YAMADA; Hideyuki AKANUMA - Web page: https://patentgrep.com/patent/US20170288545A1 ## CPC - H02M 3/158: including plural semiconductor devices as final control devices for a single load - H02M 1/08: Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters - H02M 3/1588: {comprising at least one synchronous rectifier element (H02M3/1582, H02M3/1584 take precedence)} - H02M 1/0009: {Devices or circuits for detecting current in a converter} - H02M 1/0032: {Control circuits allowing low power mode operation, e.g. in standby mode} - H02M 1/0048: {Circuits or arrangements for reducing losses (using snubbers H02M1/34)} - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A circuit device includes a first switching circuit that has one end connected to an output node, and turns on and off according to a drive signal, a second switching circuit that is connected in series with an impedance element between another end of the first switching circuit and a node having a predetermined potential, and turns off and on complementarily with the first switching circuit, a comparator circuit that outputs an output signal indicating whether or not a potential of the other end of the first switching circuit is higher than a determination level, and a control circuit that controls a level of the drive signal based on the output signal of the comparator such that the switching element enters a non-conduction state. ## Claims ### Claim 1 A circuit device comprising: a first switching circuit that enters a conduction state or a non-conduction state according to a drive signal, one end of the first switching circuit being connected to an output node, one end of a first switching element and one end of a second switching element, another end of the first switching element being connected a first power supply node, another end of the second switching element being connected a second power supply node having a lower potential than the first power supply node, the drive signal driving the second switching element, a second switching circuit that is connected between another end of the first switching circuit and a node having a predetermined potential, and enters a non-conduction state or a conduction state complementarily with the first switching circuit; an impedance element connected in series with the second switching circuit between the other end of the first switching circuit and the node having the predetermined potential; a comparator circuit that has an input terminal to which a potential of the other end of the first switching circuit is applied, and outputs an output signal indicating whether or not a potential of the input terminal is higher than a determination level; and a control circuit that, when the output signal indicating that the potential of the input terminal is higher than the determination level is output from the comparator circuit in a state in which the second switching element is in a conduction state, controls a level of the drive signal such that the second switching element enters a non-conduction state. ### Claim 2 (depends on 1) The circuit device according to claim 1, wherein the impedance element and the second switching circuit are connected in series between the other end of the first switching circuit and the first power supply node. ### Claim 3 (depends on 1) The circuit device according to claim 1, wherein the impedance element and the second switching circuit are connected in series between the other end of the first switching circuit and the second power supply node. ### Claim 4 (depends on 1) The circuit device according to claim 1, wherein the second switching circuit includes a MOS field effect transistor that is connected further on a side of the node having the predetermined potential than the impedance element. ### Claim 5 A circuit device comprising: a first switching circuit whose one end is connected to an output node to which one end of a first switching element whose another end is connected to a first power supply node and one end of a second switching element whose another end is connected to a second power supply node having a lower potential than the first power supply node are connected, and that enters a conduction state or a non-conduction state according to a drive signal that drives the second switching element; a second switching circuit that is connected between another end of the first switching circuit and a node having a predetermined potential, enters a non-conduction state or a conduction state complementarily with the first switching circuit, and has a higher on-resistance than the first switching circuit; a comparator circuit that has an input terminal to which a potential of the other end of the first switching circuit is applied, and outputs an output signal indicating whether or not a potential of the input terminal is higher than a determination level; and a control circuit that, when the output signal indicating that the potential of the input terminal is higher than the determination level is output from the comparator circuit in a state in which the second switching element is in a conduction state, controls a level of the drive signal such that the second switching element enters a non-conduction state. ### Claim 6 (depends on 1) The circuit device according to claim 1, wherein the comparator circuit further includes a second input terminal connected to the second power supply node, an offset voltage being set between the input terminal and the second input terminal, and compares the potential of the other end of the first switching circuit with the determination level that is lower than a potential of the second power supply node by the offset voltage. ### Claim 7 (depends on 5) The circuit device according to claim 5, wherein the comparator circuit further includes a second input terminal connected to the second power supply node, an offset voltage being set between the input terminal and the second input terminal, and compares the potential of the other end of the first switching circuit with the determination level that is lower than a potential of the second power supply node by the offset voltage. ### Claim 8 (depends on 1) The circuit device according to claim 1, further comprising the first switching element connected between the first power supply node and the output node and the second switching element connected between the second power supply node and the output node. ### Claim 9 (depends on 5) The circuit device according to claim 5, further comprising the first switching element connected between the first power supply node and the output node and the second switching element connected between the second power supply node and the output node. ### Claim 10 (depends on 1) A switching regulator comprising: the circuit device according to claim 1; an inductor that has one end connected to the output node and is supplied with a drive current from the first switching element; and a capacitor that is connected between another end of the inductor and the second power supply node and accumulates a charge supplied from the inductor. ### Claim 11 (depends on 5) A switching regulator comprising: the circuit device according to claim 5; an inductor that has one end connected to the output node and is supplied with a drive current from the first switching element; and a capacitor that is connected between another end of the inductor and the second power supply node and accumulates a charge supplied from the inductor. ### Claim 12 (depends on 10) An electronic apparatus comprising the switching regulator according to claim 10. ### Claim 13 (depends on 11) An electronic apparatus comprising the switching regulator according to claim 11.