DEVICE OF GENERATING PRECHARGE SIGNAL FOR STATIC MEMORY OF ON SCREEN DISPLAY SYSTEM, ESPECIALLY IN RELATION TO GUARANTEEING AN OPERATION OF A SYNCHRONOUS STATIC MEMORY EVEN THOUGH AN ASYNCHRONOUS-TYPE HORIZONTAL SYNCHRONOUS SIGNAL IS INPUTTED TO A CLOCK GENERATOR OF AN ON SCREEN DISPLAY SYSTEM

摘要

PURPOSE: A device of generating a precharge signal for a static memory of an OSD(On Screen Display) system is provided to detect an edge of a system clock, and to always generate a precharge signal at a timing when an address of a static memory is changed, thereby preventing the static memory from incorrectly operating. CONSTITUTION: A logic element(80) generates precharge signals and reversed precharge signals by responding to a system clock having a transferred level in response to a horizontal synchronous signal, and is reset by responding to a reset signal. A delay unit(82) delays the reversed precharge signals for a predetermined time, and outputs the delayed signals. A logic gate(84) generates the reset signal by responding to the delayed signals and a power reset signal.