| 摘要 |
PURPOSE:To make a through current uniform to prevent the malfunction due to noise or the like by making logical thresholds of individual inverters different from one another in plural inverter circuits consisting of C-MOS transistors Trs connected to the same power source. CONSTITUTION:Inverter circuits 1-4 consisting of P-channel PCHMOS transistors Trs QP1-QP4 and NCHMOSTrs QN1-QN4 are connected to power sources V1 and V2 together, and these circuits receive input signals from input terminals IN1-IN4 respectively and take out output signals from output terminals O1-O4 respectively. Logical thresholds VT1-VT4 of circuits 1-4 are so set that VT1>VT2>VT3>VT4 is true. When the output state of each inverter is changed, through currents I1-I4 from the power source V1 to the power source V2 do not have maximum values at the same time, and therefore, the sum of currents I1-I4 is made uniform and does not have a sharp peak value, and thus, variance of the power source potential and superposition of noise onto power supply lines are suppressed to prevent the malfunction. |
