# US 11,444,620 B2 · Drive circuit for a power semiconductor circuit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,620 B2 - Document ID: US11444620B2 - Status: Granted - Kind: B2 - Application number: 17/577,725 - Filed: 2022-01-18 - Published: 2022-07-28 - Granted: 2022-09-13 - Earliest claimed: 2021-01-26 - Assignees: Siemens Aktiengesellschaft - Applicants: Siemens Aktiengesellschaft - Inventors: Wolfgang Feil; Hauke Nannen; Tobias Andersch - Web page: https://patentgrep.com/patent/US11444620B2 ## CPC - H03K 17/689: with galvanic isolation between the control circuit and the output circuit (H03K17/78 takes precedence) - H02M 1/08: Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters - H03K 17/785: controlling field-effect transistor switches - H03K 2217/0081: Power supply means, e.g. to the switch driver - H03K: PULSE TECHNIQUE (measuring pulse characteristics G01R; modulating sinusoidal oscillations with pulses H03C; transmission of digital information H04L; discriminator circuits detecting phase difference between two signals by counting or integrating cycles of oscillation H03D3/04; automatic control, starting, synchronisation or stabilisation of generators of electronic oscillations or pulses where the type of generator is irrelevant or unspecified H03L; coding, decoding or code conversion, in general H03M) - 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) ## Abstract A drive circuit for a power semiconductor circuit may include input contact means for inputting a control signal, the control signal representing a switching command for the power semiconductor circuit, and also at least one output contact means, to which the power semiconductor circuit is connectable and which serves for outputting a switching signal to the power semiconductor circuit. Furthermore, the drive circuit comprises current path connection means for connecting the drive circuit to a current path to be switched by the power semiconductor circuit, and means for galvanically isolating the input contact means from the output contact means and the current path connection means. Circuit means which output a switching signal that switches on the power semiconductor circuit if a control signal representing the switch-on command for the power semiconductor circuit is input at the input contact means and also voltage is present at the current path connection means. ## Claims ### Claim 1 A drive circuit for a power semiconductor circuit, comprising: input contact means for inputting a control signal, the control signal representing a switching command for the power semiconductor circuit; at least one output contact means, to which the power semiconductor circuit is connectable, for outputting a switching signal to the power semiconductor circuit; current path connection means for connecting the drive circuit to a current path to be switched by the power semiconductor circuit; means for galvanically isolating the input contact means from the output contact means and the current path connection means circuit means which output a switching signal that switches on the power semiconductor circuit if a control signal representing a switch-on command for the power semiconductor circuit is input at the input contact means and a voltage is present at the current path connection means, wherein the circuit means comprise a monitoring circuit for the supply voltage of the drive circuit, the circuit means configured to operate such that the switching signal that switches on the power semiconductor circuit is output for the first time if the supply voltage exceeds a threshold value and a control signal representing the switch-on command for the power semiconductor circuit is input at the input contact means, a switching signal that keeps the power semiconductor circuit in the switched-on state is output when a control signal representing the switch-on command for the power semiconductor circuit is input at the input contact means, and a switching signal that switches on the power semiconductor circuit is not output if the supply voltage is below the threshold value and the control signal representing the switch-on command for the power semiconductor circuit is not received by the input contact means. ### Claim 2 (depends on 1) The drive circuit as claimed in claim 1, comprising: a means which, from the control signal input, photovoltaically provides an electrical energy to operate the drive circuit, wherein the circuit means are configured such that the switching signal that switches on the power semiconductor circuit for the first time is not output if the drive circuit is fed only by the photovoltaically provided electrical energy. ### Claim 3 (depends on 2) The drive circuit as claimed in claim 2, the circuit means are configured to output the switching signal that switches on the power semiconductor circuit after said switching signal has been output for the first time based on the energy provided by the means. ### Claim 4 (depends on 2) The drive circuit as claimed in claim 2, further comprising: an electrical energy storage unit, the electrical energy storage unit being chargeable by at least one of the energy generated photovoltaically from the control signal input or by an energy fed in via the current path connection means and, in a charged state, provides switching energy for switching on the power semiconductor circuit. ### Claim 5 (depends on 2) The drive circuit as claimed in claim 2, wherein the current path connection means is configured to receive the supply voltage. ### Claim 6 (depends on 2) The drive circuit as claimed in claim 2, wherein the monitoring circuit comprises a comparator having a first input and a first output, wherein a LOW level is present at the first output if the voltage at the first input falls below a first threshold value and otherwise a HIGH level is present at the first output or the first output is at high impedance; the first output is coupled to a first electronic switching means, which switches the supply voltage through to one of the output contact means in the event of a HIGH level at the first output of the comparator or in the event of a high-impedance state of the first output of the comparator and is at high impedance in the event of a LOW level at the first output of the comparator; and a voltage divided from the supply voltage of the circuit is fed in via a voltage divider at the first input. ### Claim 7 (depends on 6) The drive circuit as claimed in claim 6, the comparator of which comprises a second input and a second output, wherein a LOW level is present at the second output if the voltage at the second input exceeds a second threshold value and otherwise a HIGH level is present at the second output or the second output is at high impedance; the second output is coupled to a second electronic switching means, which switches the input of the first electronic switching means through to ground in the event of a high level at the second output of the comparator or in the event of a high-impedance state of the second output of the comparator and is at high impedance in the event of a LOW level at the second output of the comparator; and at the second input the supply voltage is present or a voltage is fed in via a voltage divider if a control signal representing the switch-on command is present at the input contact means and otherwise no signal or ground is present at the second input. ### Claim 8 (depends on 1) A semiconductor contactor comprising the drive circuit of claim 1.