Circuit with hot-plug protection, corresponding electronic device, vehicle and method

A method of providing hot-plug protection in an integrated circuit comprising a plurality of input pins and at least one output pin, the integrated circuit including a hot-plug protection circuit, wherein the method comprises:

• providing a plurality of electrical connections, wherein input pins in the plurality of input pins are electrically coupled to a common node in the hot-plug protection circuit via respective electrical connections in the plurality of electrical connections;
• arranging clamping circuitry coupled between the common node and the at least one output pin, the clamping circuitry being activatable as a result of a voltage spike applied across the clamping circuitry;
• and
• coupling a power limiting circuit between the at least one output pin of the integrated circuit and a reference pin and comprising an electronic switch coupled between the at least one output pin of the integrated circuit and the reference pin, and wherein the electronic switch comprises an MOS transistor, a capacitor coupled between a gate and a source of the MOS transistor, a first resistor coupled between the gate and a control terminal of the electronic switch, and a second resistor coupled between the source and the control terminal of the electronic switch, wherein a drain of the MOS transistor is directly coupled to the at least one output pin of the integrated circuit, and wherein the source of the MOS transistor is directly coupled to the reference pin,
• wherein the plurality of electrical connections and the clamping circuitry provide respective current discharge paths between the input pins in the plurality of input pins and the at least one output pin, the respective current discharge paths configured to become conductive as a result of a voltage spike applied to any of the input pins in the plurality of input pins being transferred to the common node via the respective electrical connection in the plurality of electrical connections electrically coupling any of the input pins to the common node.

An integrated circuit comprising a plurality of input pins and at least one output pin, the integrated circuit including a hot-plug protection circuit, wherein the hot-plug protection circuit comprises:

• a plurality of electrical connections, wherein input pins in the plurality of input pins are electrically coupled to a common node in the hot-plug protection circuit via respective electrical connections in the plurality of electrical connections;
• and
• clamping circuitry coupled between the common node and the at least one output pin, the clamping circuitry being activatable as a result of a voltage spike applied across the clamping circuitry,
• wherein the plurality of electrical connections and the clamping circuitry provide respective current discharge paths between the input pins in the plurality of input pins and the at least one output pin, the respective current discharge paths configured to become conductive as a result of a voltage spike applied to any of the input pins in the plurality of input pins being transferred to the common node via the respective electrical connection in the plurality of electrical connections electrically coupling any of the input pins to the common node, and
• a power limiting circuit coupled between the at least one output pin of the integrated circuit and a reference pin and comprising a high-impedance current path and an electronic switch coupled between the at least one output pin of the integrated circuit and the reference pin, wherein the power limiting circuit is configured to keep inrush power below a break-point of the clamping circuitry, and wherein the electronic switch comprises an MOS transistor, a capacitor coupled between a gate and a source of the MOS transistor, a first resistor coupled between the gate and a control terminal of the electronic switch, and a second resistor coupled between the source and the control terminal of the electronic switch, wherein a drain of the MOS transistor is directly coupled to the at least one output pin of the integrated circuit, and wherein the source of the MOS transistor is directly coupled to the reference pin, wherein the plurality of electrical connections coupling the input pins in the plurality of input pins to the common node in the hot-plug protection circuit comprise only a single respective diode coupled between the respective pin in the plurality of input pins and the common node.