A Nonvolatile Ceramic Memory Device -- An Alternate Structure

摘要

A newly designed nonvolatile ceramic memory device was fabricated and evaluated. This device is 0.55 in. in diameter, 0.010 in. in thickness, and contains 12 memory cells. For each cell information is inserted on one lead and readout is taken on a second lead; therefore, no internal mechanical switching is required. Each memory cell has two stable states: one that produces a high voltage output (one) and one that produces a low voltage output (zero). These two conditions, which remain stable even when the power is switched off, enable each cell to store one binary bit that is recoverable nondestructively by a simple voltage detecting circuit. From -50 to +80C the output voltages vary slightly with temperature, but the lowest voltage one is never less than 1.4 V greater than the highest voltage zero. One is written into the memory cell by a d-c voltage of +360 V; the zero, by a d-c voltage of -270 V. Both voltages are applied for a noncritical time of about 1 sec. (Author)