| 摘要 |
PURPOSE:To reduce current consumption due to a non-selective chip by preventing the non-selective chip from the flow of through current in multi-chip constitution. CONSTITUTION:Control signals C1-C3 are supplied from a CPU 11 to control input terminals IA-IC of LSIs A-C respectively. A high level signal is applied to the control input terminals IA-IC at the time of nonselection and a low level signal at the selection. If the LSI A is selected, the CPU 11 sets up the C1 to the low level and the C2, C3 to the high level. Since the high level control signal is applied to the LAIs B, C, an n type TR n12 is always connected and a p type TR p11 is always disconnected. Therefore, an output 0 is always kept at earth potential. Since the TR p11 is always disconnected even if an input signal I is changed, through current passing through n11, n12, p11 and p12 does not flow. |
