Data retention | Fatigue | Data retention after fatigue | Results of product reliability tests |
FUJITSU FRAM Quality & Reliability
Reliability(3/4)
== Data retention after fatigue ==
Data retention and fatigue are related to each other in the actual use of a FRAM. The retention characteristic of a memory cell given more fatigue is considered to be generally weaker than that of a memory cell given less fatigue. (Figure 11) To study that relationship, data retention is tested on devices using a various number of fatigue stress cycles. It has been confirmed that 2 x 10EXP7 fatigue stress cycles do not affect the retention characteristic. (See Table 4 Test data.)
Figure 11. Retention after fatigue stress (prediction)
Table 4. test data
| No. of test cycles | Results of storage at a high temperature of 150°C (No. of defective units/no. of tested units) |
||||
| cycle time | 168h | 500h | 1kh | 2kh | 3kh |
| 2 x 10EXP7 (125°C 6.0V) | 0/50 | 0/50 | 0/50 | 0/50 | 0/50 |
