RAM FAULT DETECTING CIRCUIT AND RAM ENERGY CONSUMPTION SUPPRESSING CIRCUIT

摘要

PURPOSE:To provide the RAM fault detecting circuit and RAM energy consumption suppressing circuit for immediately detecting a fault and suppressing energy consumption when the fault is generated in the enable control of a RAM. CONSTITUTION:Fixed data are inserted from a first fixed data generating means 12 to input data and inputted to a RAM 11, the fault in the enable control of the RAM 11 is detected and an alarm signal is outputted by comparing the read fixed data with data from a second fixed data generating means 15 at a fixed data collating means 16 although the read of the RAM 11 is controlled in a disable state. The alarm signal is held in an alarm holding means, outputted to an address generating means 13, so that address data are fixed. Thus, even when the enable control is made abnormal and the RAM 11 can not be turned to the disable state, the output data of the RAM 11 are prevented from changing, energy consumption is suppressed, and heat generation is suppressed.