Write control circuit for semiconductor memory device

摘要

A write control circuit that generates a control signal to initiate a write operation for a semiconductor memory device, such as an EEPROM, compensates for fluctuations in the supply voltage. The write control circuit includes a control potential generator that produces a first control potential which is kept higher than the ground potential and a second control potential which is kept lower than the supply potential. A first transistor is connected to the supply potential and receives a write potential at its gate. A second transistor is connected between the first transistor and ground and receives the first control potential at its gate. A third transistor is connected to the supply potential and receives the second control potential at its gate. A fourth transistor is connected between the third transistor and ground and receives a potential from a first node between the first and second transistors at its gate. The control signal is generated at a second node between the third and fourth transistors. The control signal is activated when the write potential reaches a certain value.