| 摘要 |
PURPOSE:To enable to readily confirm the presence or absence of melted fuse F by utilizing a semiconductor substrate and a P-N junction by a diffused layer formed on the substrate. CONSTITUTION:A P-N junction D1 existed between a pad P1 and a pad P2 for biasing a semiconductor substrate is connected through a fuse F between the pads P1 and P2. In other words, a current flowed between the pads P1 and P2 flows always through the fuse F, and other circuit connected to the pad P1 is all a gate input circuit. A power source voltage Vcc is applied to the pad P1 when the fuse F is melted, and an MOSFETQ is turned ON by a gate signal phi of a current controlling MOSFETQ to flow a melting current through the fuse F. The confirmation after the fuse F is melted is performed so that the current does not flow by maintaining the pad P1 at low voltage level to the pad P2 of the same voltage as the substrate and applying the voltage of the polarity that a forward current flows to the P-N junction diode D1. |
