| 摘要 |
PURPOSE:To increase the number of circuits which are stored in a single chip of a semiconductor IC by connecting the transfer gates controlled by the control signals to the gates of the p and n type MOS transistors respectively. CONSTITUTION:When a control signal is turned into an ON signal, the transfer gates 7 and 8 set on a signal line which connects an inverter 1 and a logic circuit 4 receive the ON signal and open to separate the inverter 1 from the circuit 4. Furthermore the transfer gates 6 and 7 set on the signal line receive the ON signal and are turned on to turn off a p type MOS transistor TR2 and an n type MOS TR3 contained in the inverter 1. As a result, the output side of a 3-state logic circuit has high impedance. Thus it is possible to increase the number of circuits stored in a single chip of a semiconductor IC. |
