A display device includes more than one IC chip formed on a substrate. Analog signals are applied to the ICs with a point-to-point structure. Digital signals are applied to the ICs with a cascade structure. Wirings applying digital signals are widened in the areas having room available so that electrical resistance can be reduced. Wirings in areas not having enough room to widen are applied with multi path technology to reduce electrical resistance. Multi contact technology may be applied to contact the ICs to a glass substrate.