| 摘要 |
PURPOSE:To secure the hysteresis for the input/output characteristics by supplying the input voltage to the inverter circuit using the MOS transistor via the two-way level shift circuit. CONSTITUTION:The potential at point A and B are set to VA and VB respectively, and the threshold level of MOS transistors Q3 and Q4 is set to VT. As a result, the relation of VA = AB + VT and VB = VA + VT can be obtained in the case of VA>VB and VA<VB respectively. And now if VT = 1V is obtained and VA increases to exceed VT, from which point transistor Q3 is turned on, and VB follows VA to increase. If VA is lowered at the time point when the charging is given to VB = 4V at VA = 5V, Q3 is turned off. And transistor Q4 is turned on with VA = 3V, and VB follows VA to decrease. In this way, the hysteresis emerges to the input/ output characteristics of two-way level shift circuit 2 comprising transistors Q3 and Q4. And accordingly, the hysteresis emerges to the input/output characteristics of inverter circuit 1 comprising transistors Q1 and Q2. |
