An interface circuit of a vehicle-mounted control unit, wherein the interface circuit comprises: an H-bridge circuit, an input branch; and a pull-up network, wherein an input end of the H-bridge circuit is connected to a controller, and an output end of the H-bridge circuit is connected to an interface port IO of the interface circuit; a first end of the input branch is connected to the interface port IO, and a second end of the input branch is connected to the controller; and the pull-up network comprises a local interconnect network LIN bus pull-up resistor branch and a single edge nibble transmission SENT bus pull-up resistor branch, wherein the LIN bus pull-up resistor branch is provided with a LIN bus pull-up resistor, a diode, and a first switch component, wherein a first end of the LIN bus pull-up resistor is connected to a LIN bus power supply, a second end of the LIN bus pull-up resistor is connected to an anode of the diode, and a cathode of the diode is connected to the interface port IO by using the first switch component; the SENT bus pull-up resistor branch is provided with a SENT bus pull-up resistor and a second switch component, wherein a first end of the SENT bus pull-up resistor is connected to a SENT bus power supply, and a second end of the SENT bus pull-up resistor is connected to the interface port IO by using the second switch component; on-off of the first switch component is controlled by the controller by using a first control branch and/or on-off of the second switch component is controlled by the controller by using a second control branch; and the interface circuit is configured as one of the following interfaces under the control of the controller: an H-bridge output interface, a 12 V power output interface, a 5 V digital signal output interface, a 5 V digital signal input interface, a 12 V digital signal input interface, a LIN bus interface, and a SENT bus interface. an input end of the H-bridge circuit is connected to a controller, and an output end of the H-bridge circuit is connected to an interface port IO of the interface circuit; a first end of the input branch is connected to the interface port IO, and a second end of the input branch is connected to the controller; and the pull-up network comprises a local interconnect network LIN bus pull-up resistor branch and a single edge nibble transmission SENT bus pull-up resistor branch, wherein the LIN bus pull-up resistor branch is provided with a LIN bus pull-up resistor, a diode, and a first switch component, wherein a first end of the LIN bus pull-up resistor is connected to a LIN bus power supply, a second end of the LIN bus pull-up resistor is connected to an anode of the diode, and a cathode of the diode is connected to the interface port IO by using the first switch component; the SENT bus pull-up resistor branch is provided with a SENT bus pull-up resistor and a second switch component, wherein a first end of the SENT bus pull-up resistor is connected to a SENT bus power supply, and a second end of the SENT bus pull-up resistor is connected to the interface port IO by using the second switch component; on-off of the first switch component is controlled by the controller by using a first control branch and/or on-off of the second switch component is controlled by the controller by using a second control branch; and the interface circuit is configured as one of the following interfaces under the control of the controller: an H-bridge output interface, a 12 V power output interface, a 5 V digital signal output interface, a 5 V digital signal input interface, a 12 V digital signal input interface, a LIN bus interface, and a SENT bus interface.