Patent ID: 6396610
Filing Date: 2002-05-28
Classification: G05F,H03K

Abstract:
A semiconductor integrated circuit comprising:a signal source circuit generating a signal to be transmitted; a light emitting element driver circuit supplying a signal outputted from said signal source circuit to a light emitting element disposed at a position outside the semiconductor integrated circuit as a drive signal; and a light emitting element connecting terminal connected to the output end of said light emitting element driver circuit and to which the light emitting element is connected, wherein said signal source circuit, said light emitting element driver circuit, and said light emitting element connecting terminal are integrally formed on one semiconductor chip, said light emitting element driver circuit comprising; a first pair of MOS field effect transistors connected in a differential operating manner, to which a signal outputted from said signal source circuit is applied, and a current mirror circuit comprising a second pair of MOS field effect transistors, said second pair of MOS field effect transistors connected between the output side of one of said first pair of said MOS field effect transistors connected in differential operating manner and said light emitting element connecting terminal, wherein said light emitting element and one of the second pair of said MOS field effect transistors of said current mirror circuit are connected in series between power supply lines.