Microchip EERAM Combines SRAM and Backup EEPROM into a Single Chip

Most micro-controllers comes with both SRAM volatile memory, and flash or EEPROM for non-volatile (persistent) memory, but Texas Instruments – and other companies – have been selling MCUs with FRAM (Ferroelectric Random Access Memory) and standalone FRAM chip, a non-volatile memory that delivers performance and power efficiency similar to SRAM, and much better endurance that either flash or EEPROM. You don’t see FRAM in that many MCUs and solutions, because it’s more expensive than having SRAM + flash, but some applications requiring ultra low power consumption and non-volatile storage write capabilities may benefit from the technology. Those include data logging, sensor networks, and batteryless applications. Microchip has also it own technology with EERAM, a non-volatile SRAM memory that includes a “shadow” EEPROM used to automatically backup data on power down with a small external capacitor providing enough power to save SRAM to the EEPROM. Once power is recovered (Vdd > […]

FRAM (Ferroelectric Random Access Memory) and Texas Instruments MSP430FR57xx MCUs

I’ve recently received a complementary book entitled “Texas Instruments FRAM MCUs for DUMMIES” sent by Mouser, that provides technical and practical information about FRAM (Ferroelectric Random Access Memory) – pronounced F-RAM – and Texas Instruments MSP430FR57xx MCU series which makes use of this relatively new type of memory. FRAM is a non-volatile memory with power and write speed & endurance characteristics that almost matches SRAM capabilities, and leave traditional Flash and EEPROM memory in the dust in terms of performance, as you can see from the table and diagram below. At constant speed, FRAM consumes 250x less than Flash/EEPROM. Please note the FRAM write speed also depends on the MCU used, and a MCU @ 8MHz can write the FRAM @ 1400 kBps (Source: TI). However, you won’t see this type of memory in devices like smartphones anytime soon because the maximum size currently manufactured is 1MB, density is higher […]