| 摘要 |
PURPOSE:To detect simply a storage device which is formed by the storage element of a low output signal, by generating a potential difference between both input terminals in case that input terminals of a differential amplification-type level converter are restricted to a fixed voltage. CONSTITUTION:At a write time, when transistor 6 is turned off, capacitors 4 and 5 at the output end of differential amplifier 1 have a potential lower or higher than the operating center voltage of differential amplification-type level converter 13 by a prescribed value due to resistances 14 and 15 connected to diodes 9 and 11 of a power source circuit. Then, the potential at input terminals F and E of converter 13 have a voltage lower or higher than the operting center voltage by a prescribed threshold voltage. Immediately after these restriction voltages are released at a read time by the turning-on of transistor 6, one of voltages at terminals E and F has the level lowered and the other has the level raised by the charging voltage of capacitors 4 and 5, and the magnitude of output signals from storage elements is detected by comparator 13, thereby removing simply storage devices formed by low-output signal storage elements. |
