Patent ID: 8416544

Claim:
A semiconductor integrated circuit comprising: a first operation voltage supply terminal; a second operation voltage supply terminal; a third operation voltage supply terminal; a first internal circuit; a second internal circuit; a third internal circuit; a first electrostatic discharge protection circuit; a second electrostatic discharge protection circuit; a third electrostatic discharge protection circuit; and a coupling midpoint, wherein operation voltages of mutually different voltage levels can be supplied to the first, second, and third operation voltage supply terminals from outside the semiconductor integrated circuit, wherein the first internal circuit can operate at a first operation voltage supplied through the first operation voltage supply terminal, the second internal circuit can operate at a second operation voltage supplied through the second operation voltage supply terminal, and the third internal circuit can operate at a third operation voltage supplied through the third operation voltage supply terminal, and wherein the first electrostatic discharge protection circuit is coupled between the first operation voltage supply terminal and the coupling midpoint, the second electrostatic discharge protection circuit is coupled between the second operation voltage supply terminal and the coupling midpoint, and the third electrostatic discharge protection circuit is coupled between the third operation voltage supply terminal and the coupling midpoint.