| 摘要 |
<p>A non-volatile random access memory (NVRAM) cell (10) of condensed size employs a pair of programmable threshold voltage devices (40b, 42b), e.g. MNOS, SNOS, SONOS or floating gate transistors, in which different threshold voltage levels are established in accordance with the data signal levels existing on the data nodes (DT, DC) of a flip flop (12), when the volatile data is stored in the programmable devices. During recall of the non-volatile stored data to the data nodes of the flip flop, the programmable devices (40b, 42b) actively conduct current to the data nodes (DT, DC) to set the flip flop (12) in the same state that existed when the data was stored. Power is supplied to the flip flop independently of the power supplied to the programmable devices. A single polysilicon conductor (28) forms gates of transistors (40c, 42c) which connect the programmable devices (40b, 42b) to the data nodes (DT, DC) and the gates (20, 22) of the flip flop transistors (16, 18). A load device (24, 26) for each data node is integrated in the single polysilicon conductor (28). A dynamic program inhibit capability is achieved in each programmable device (40b, 42b) during the store operation, by applying a series of programming signal pulses.</p> |
