Dynamischer Speicher mit wahlfreiem Zugriff mit Mittelspannungsgenerator zur Energieversorgungsunterbrechung beim Prüfbetrieb

摘要

When a dynamic random access memory device is powered with an external power voltage (Vcc), a first intermediate voltage generator (14b) produces an intermediate voltage from the external power voltage for supplying to the counter electrodes of the storage capacitors (11 b) of memory cells and a precharge unit (13b), and the first intermediate voltage generator is replaced with a second intermediate voltage generator (14c) after the internal power voltage (Vint) becomes stable, wherein a switch transistor (16) blocks the counter electrodes and the precharge unit from the second intermediate voltage generator during a test operation on bit lines, thereby effectively screening out defective products.