Methods and systems for detection and monitoring of power supply voltage and voltage reference circuitry are provided. Another object is to prevent a defect of a semiconductor device due to poor connection between an antenna and an integrated circuit in a semiconductor device having the integrated circuit and the antenna formed over one substrate. The mounting bar projects rearwardly from a rear wall, and includes a vertically extending mounting bores. The clock buffer includes an inverter core portion and an electric current suppressing portion.