Electrostatic protection circuit, circuit board, and electrostatic protecting method

An electrostatic protection circuit comprising a first relay and a second relay,

• wherein a control terminal of the first relay and a control terminal of the second relay are configured to be connected to a power supply of a system circuit respectively;
• wherein the first relay and the second relay are connected in series between the system circuit and a ground terminal to form a charge release path, wherein the first relay is switched from a short circuit state to an open circuit state when the system circuit is powered on and is switched from the open circuit state to the short circuit state when the system circuit is powered off, and wherein the charge release path is in a turn-on state after the first relay is switched to the short circuit state, thereby releasing an electrostatic charge in the system circuit;
• and
• wherein the second relay is switched from the open circuit state to the short circuit state when the system circuit is powered on and after the first relay is in the open circuit state for a first time period, and when the system circuit is powered off and after the second relay is in the short circuit state for a second time period, the second relay is switched to the open circuit state, and wherein the charge release path is in a turn-off state after the second relay is switched to the open circuit state, thereby stopping the release of the electrostatic charge in the system circuit,
• wherein the second time period is a delay time of the second relay, and wherein the first time period is a difference between the delay time of the second relay and a delay time of the first relay.