Semiconductor storage device

Abstract

Abstract PURPOSE:To obtain circuit constitution especially suitable for a CMOS with no occurrence of malfunction by using a power supply voltage detecting circuit containing a flip-flop circuit to the output of a semiconductor storage device containing a miswrite preventing circuit of ON/OFF modes of the power supply. CONSTITUTION:A write signal WE is applied to a transistor TRQ8 where a current is cut and the signal WE rises up to just the same level as the power supply voltage Vcc. If the signal WE rises up to the level of the Vcc owing to noises, no flip-flop is set as long as the Vcc that sets connection node N3 between 1st and 2nd TRsQ8 and Q9 at a certain level necessary to set a flip-flop is not available. Thus a miswrite preventing circuit outputs no write permission signal to an output terminal VOK and therefore no malfunction is produced. When the node N3 exceeds once said level for a period during which the flip- flop is set, e.g., 5-6sec, the flip-flop is never inverted regardless of the types of noises produced thereafter. Thus the output VOK (write permission signal) is free from noise effects.

Inventors

• 👤 Hideki Arakawa
• 👤 秀貴 荒川

Bibliographic Details