Patent ID: 7782583

Claim:
An electrostatic discharge protection device having a power supply voltage line and a ground voltage line and protecting an internal circuit from an electrostatic current flowing into an input/output pad, comprising: a voltage detection unit detecting a first detection voltage and a second detection voltage by forming an electrical connection between the power supply voltage line and the ground voltage line in response to an alternating current component of the electrostatic current; a first transfer unit transferring the electrostatic current into the power supply voltage line by forming an electrical connection between the input/output pad and the power supply voltage line in response to the first detection voltage; a second transfer unit transferring the electrostatic current into the ground voltage line by forming an electrical connection between the input/output pad and the ground voltage line in response to the second detection voltage; and a discharge unit discharging the electrostatic current flowing into the power supply voltage line or the ground voltage line by forming an electrical connection between the power supply voltage line and the ground voltage line in response to the second detection voltage.