Electronic device connecting structure and function expansion device

A function expansion device comprising:

• a second EMI shield;
• a second signal line enclosed by the second EMI shield;
• a second signal earth line enclosed by the second EMI shield;
• a second interface connector to which the second signal line and the second signal earth line are connected;
• an EMI connecting portion connected to the second EMI shield and comprising a conductor connected to a first EMI shield when hot docked with a portable computer comprising the first EMI shield, a first signal line enclosed by the first EMI shield, a first signal earth line enclosed by the first EMI shield, and a first interface connector to which the first signal line and the first signal earth line are connected;
• and
• an ESD contact portion connected to the second EMI shield, higher in impedance than the EMI connecting portion, and coming in contact with the first EMI shield earlier than the EMI connecting portion at the time of hot docking.

A portable computer comprising:

• a second EMI shield;
• a second signal line enclosed by the second EMI shield;
• a second signal earth line enclosed by the second EMI shield;
• a second interface connector to which the second signal line and the second signal earth line are connected;
• an EMI connecting portion connected to the second EMI shield and connected to a first EMI shield when hot docking with a function expansion device comprising the first EMI shield, a first signal line enclosed by the first EMI shield, a first signal earth line enclosed by the first EMI shield, and a first interface connector to which the first signal line and the first signal earth line are connected;
• and
• an ESD contact portion connected to the second EMI shield, higher in impedance than the EMI connecting portion, and coming in contact with the first EMI shield earlier than the EMI connecting portion at the time of hot docking.

A method comprising:

• activating a portable computer;
• bringing the portable computer closer to a function expansion device with the portable computer active;
• performing ESD contact between an EMI shield of the portable computer and an EMI shield of the function expansion device in a high-impedance state with the portable computer active;
• and
• performing EMI connection between the EMI shield of the portable computer and the EMI shield of the function expansion device with the portable computer active subsequent to performing the ESD contact.