| 摘要 |
PURPOSE:To prevent an influence of noise at the time of discharging of the electric charge of a bus line from a gate circuit by separating respective wirings Vss of a transistor TR, which discharges the electric charge of a bus line, and its control gate circuit. CONSTITUTION:A low potential-side wiring Vss2 of a TR Tr3 which discharges the bus line of the output stage of each of bus drivers 11, 12,... and a low potential-side wiring Vss1 of the gate circuit which supplies an input signal to the TR Tr3 of the input means of the bus driver are separated from each other. Wirings Vss1 and Vss2 are not separated up to a bus driver group 10 and are branched into two at the entrance of he bus driver group. There are 32 buses; and when only a bus BUS1 is in the high level and the other are in the low level, a large current due to bus line discharging flows to the wiring Vss2, and the potential rises in a node (c), and the potential of the precharged bus BUS1 is not reduced. |
