| 摘要 |
PURPOSE:To discriminate variation in source voltage precisely and prevent malfunction by dividing the source voltage through conduction type MOSFETs which are supplied with the source voltage as a bias voltage. CONSTITUTION:The source voltage is divided through series-connected P type FETs Q45 and Q46 which are supplied with the source voltage VCC as a bias voltage and compared by an inverter IV2 with a reference voltage, thereby discriminating variation in the source voltage. Therefore, the semiconductor substrate of single-crystal P type silicon of the integrated circuit of an internal synchronism type dynamic RAM formed on the substrate is not affected by the bias voltage developed in the substrate, and a desired divided voltage of the source voltage is obtained to detect variation in the source voltage accurately, so that the variation in the source voltage is discriminated with high precision. Consequently, a proper timing signal is generated even when the source voltage varies, and the semiconductor integrated circuit of the dynamic RAM is prevented from malfunctioning. |
