| 摘要 |
<p>PURPOSE:To decrease the current consumption by cutting off forcibly the current path of an internal circuit even though an external clock is active when a current is applied. CONSTITUTION:When a power supply level has a rise when a power supply is applied, the transistors (TR) QP1 and QP2 are turned on with node points N2 and N5 set at a high earth level and a high power supply level respectively. When an external clock phi is kept active at a low level, the output of an inverter 17 is set at a high level with the output of a NOR circuit NO1 set at a low level and a control signal PON set at a high level respectively. Thus the current paths of an output data buffer, etc., are forcibly cut off. When the power supply level is stable at a high level, the node points N are set at low levels and the circuit NO1 produces a high output with the signal PON changed to a low level when the clock phi is set at a high level before a normal cycle. As a result, the current path of an internal circuit is forcibly cut off even though the clock phi is active when the power supply is applied.</p> |
