Integrated Circuits Used 74LS03 Procedure Add IC 74LS03 into ICBase-3 (74LS03).Connect Pin-7 (Ground) of ICBase-3 (74LS03) to GND Port.Connect Pin-20 (VCC) of ICBase-3 (74LS03) to VCC Port.Add IC 74LS03 into ICBase-2 (74LS03).