Slide 1 Slide 2 Slide 3 Slide 4 Slide 5 Slide 6 Slide 7 Slide 8 Slide 9 Slide 10 Slide 11 Slide 12 Slide 13 Slide 14 Slide 15 Slide 16 Slide 17 Slide 18 Slide 19 Slide 20 Slide 21 Slide 22 Slide 23 Slide 24 Slide 25 Slide 26 Slide 27 Slide 28 Slide 29 Slide 30 Slide 31 Slide 32 Slide 33 Slide 34 Product List
MSP430FR57xx FRAM Microcontrollers Slide 5

A single FRAM cell can be considered a dipole capacitor consisting of a film of ferroelectric material (ferroelectric crystal) between two electrode plates. Storing a ‘1’ or ‘0’ (writing to FRAM) simply requires the polarizing of the crystal in a specific direction using an electric field. This makes FRAM very fast, easy to write to and capable of meeting high endurance requirements. Reading from FRAM requires the application of an electric field across the capacitor similar to a write. Depending on the state of the crystal, it may get re-polarized, thereby emitting a large induced charge. This charge is then compared to a known reference in order to estimate the state of the crystal. The stored data bit ‘1’ or ‘0’ is inferred from the induced charge. In the process of reading the data, the crystal that is polarized in the direction of the applied field loses its current state. Hence every read needs to be accompanied by a write-back to restore the state of the memory location. In the MSP430FR57xx family this is inherent to the nature of the FRAM memory and is completely transparent to the end user.

PTM Published on: 2012-04-19