ZHCA829G October 2014 – August 2021 MSP430F2001 , MSP430F2002 , MSP430F2003 , MSP430F2011 , MSP430F2012 , MSP430F2013 , MSP430F2013-EP , MSP430F2101 , MSP430F2111 , MSP430F2112 , MSP430F2121 , MSP430F2122 , MSP430F2131 , MSP430F2132 , MSP430F2232 , MSP430F2234 , MSP430F2252 , MSP430F2254 , MSP430F2272 , MSP430F2274 , MSP430F2274-EP , MSP430F233 , MSP430F2330 , MSP430F235 , MSP430F2350 , MSP430F2370 , MSP430F2410 , MSP430F2416 , MSP430F2417 , MSP430F2418 , MSP430F2419 , MSP430F247 , MSP430F2471 , MSP430F248 , MSP430F2481 , MSP430F249 , MSP430F249-EP , MSP430F2491 , MSP430F2616 , MSP430F2617 , MSP430F2618 , MSP430F2619 , MSP430F2619S-HT , MSP430FR2032 , MSP430FR2033 , MSP430FR2110 , MSP430FR2111 , MSP430FR2153 , MSP430FR2155 , MSP430FR2310 , MSP430FR2311 , MSP430FR2353 , MSP430FR2355 , MSP430FR2433 , MSP430FR2475 , MSP430FR2476 , MSP430FR2532 , MSP430FR2533 , MSP430FR2632 , MSP430FR2633 , MSP430FR2672 , MSP430FR2673 , MSP430FR2675 , MSP430FR2676 , MSP430FR4131 , MSP430FR4132 , MSP430FR4133 , MSP430G2001 , MSP430G2101 , MSP430G2102 , MSP430G2111 , MSP430G2112 , MSP430G2121 , MSP430G2131 , MSP430G2132 , MSP430G2152 , MSP430G2153 , MSP430G2201 , MSP430G2202 , MSP430G2203 , MSP430G2210 , MSP430G2211 , MSP430G2212 , MSP430G2213 , MSP430G2221 , MSP430G2230 , MSP430G2230-EP , MSP430G2231 , MSP430G2231-EP , MSP430G2232 , MSP430G2233 , MSP430G2252 , MSP430G2253 , MSP430G2302 , MSP430G2302-EP , MSP430G2303 , MSP430G2312 , MSP430G2313 , MSP430G2332 , MSP430G2332-EP , MSP430G2333 , MSP430G2352 , MSP430G2353 , MSP430G2402 , MSP430G2403 , MSP430G2412 , MSP430G2413 , MSP430G2432 , MSP430G2433 , MSP430G2444 , MSP430G2452 , MSP430G2453 , MSP430G2513 , MSP430G2533 , MSP430G2544 , MSP430G2553 , MSP430G2744 , MSP430G2755 , MSP430G2855 , MSP430G2955 , MSP430I2020 , MSP430I2021 , MSP430I2030 , MSP430I2031 , MSP430I2040 , MSP430I2041
单个 FRAM 单元可被视为一个偶极电容器,它由两个电极板之间的铁电材料(铁电晶振)薄膜构成。存储“1”或“0”时(写入 FRAM 时),只需使用电场将晶振向特定方向极化。这使得 FRAM 速度非常快,易于写入,能够充分满足高耐用性要求。
与写入时类似,从 FRAM 中读取也需要在电容器上施加一个电场。根据晶振的状态,可将其重新极化,从而释放出一个大感应电荷。这个电荷随即与一个已知基准进行对比,从而估计晶振所处的状态。存储的数据位“1”或“0”从感应电荷推断得出。在读取数据的过程中,按施加的电场方向极化的晶振会失去当前的状态。因此每次读取后,都必须进行回写操作以恢复存储位置的状态。对于 TI 的 MSP430 FRAM MCU,这是 FRAM 实施方案所固有的特性,对应用而言是完全透明的。回写机制还可防止断电,并在所有断电事件中安全完成。
FR4xx 电源管理系统通过在断电时将 FRAM 电源轨与器件电源轨隔离开来实现这一目的。FRAM 电源电路还使用内置低压降稳压器 (LDO) 和一个电容器,该电容器存储足够的电荷以在发生电源故障时完成当前回写操作。
更多有关 FRAM 和 FRAM 控制器的信息,请参阅Topic Link Label7.5。