| 摘要 |
PROBLEM TO BE SOLVED: To maximize a margin of on/off ("1"/"0") determination when an external load receives a rectangular wave pulse from a digital circuit while suppressing influence by a ground bounce on a analog circuit when a digital circuit drives the external load, such as a memory in a semiconductor integrated circuit on which the digital circuit and the analog circuit are loaded together. SOLUTION: A main driver circuit 7 for driving the external load 3 is driven through a multistage voltage control type pre-driver 6 provided with a plurality of stages of inverters INV1 to INV3 so as to switch the number of use stages of the inverters INV1 to INV3 by a switching circuit 12. When the level of a ground bounce detected by a noise detection circuit 13 is small, only the inverter INV3 is used to make the dullness of the rectangular wave pulse small, and when it is large, the inverters INV1 to INV3 are used to suppress the ground bounce. COPYRIGHT: (C)2011,JPO&INPIT |
