Patent ID: 8749930

Claim:
A protection circuit comprising: a first diode between a signal line and a first power supply line; a second diode between the signal line and the first power supply line in parallel to the first diode; and a third diode between the first power supply line and a second power supply line, wherein the first diode is a diode-connected transistor, wherein the second diode has a PIN junction or a PN junction, wherein each of the first diode and the second diode is electrically connected to the signal line and the first power supply line such that a reverse bias is applied to each of the first diode and the second diode when a potential of the signal line is higher than a potential of the first power supply line, wherein a channel length of the first diode is 2 μm to 6 μm, and wherein a channel width of the first diode is 3000 μm to 4000 μm.