| 摘要 |
<p>PURPOSE:To prevent overcurrent and to prevent the erase of stored information and the generation of damage of a memory element itself which exert influence upon other elements by detecting supplied voltage, supplying a complementary signal to a switching means and selecting a current limiting means. CONSTITUTION:The power supply voltage is detected by a transistor (TR) TR0 and voltage dividing resistors R1, R2 in a C-MOS static memory element 1, a complementary detecting voltage is generated through inverters INV1, INV2 and TRs TRH, TRL are turned on by low level outputs through respective IV1, IV2 accordance with the use of a power supply of 5V or the like and a battery power supply of 2V. Then, a current limiting circuit in a memory main circuit is automatically selected in accordance with the used power supply. Therefore, overcurrent is prevented indenpendently of the power supplies having different voltages and the earse of the stored information and the generation of damage of the memory element itself which exert influence upon other elements are prevented.</p> |
