Embedding FRAM into the MCU has reduced total footprint and cost while simplifying system design. The high speed non-volatile nature of FRAM offers another unique advantage: it writes so fast that the MCU does not need to wait for the write operation to complete (see further advantages below). The architecture eliminates chip-to-chip interconnects, which significantly improves the transaction speed and internal bus interface between MCU and memory, enabling performance that cannot be matched by either Flash or E2PROM.
MB95R203A is ideal for a variety of general-purpose applications, including metering devices, consumer electronics products, healthcare, and industrial systems.
The MCU device is the successor to a Fujitsu F2MC-8FX family member of high-performance 8-bit MCUs. It incorporates state-of-the-art non-volatile FRAM, featuring ultra-high access speeds and the ability to retain data in memory without power. Due to a reduced internal write voltage, the FRAM can be erased and re-written 100,000 times more compared to its predecessor. The read/write endurance is specified as 1015 times, with data retention guaranteed for 10 years. Assuming that memory is accessed with four cycles at a constant rate of 10MHz, it will take more than 12.5 years to exhaust the ferroelectric material.
MB95R203A incorporates 8 Kbytes of user-accessible FRAM, which can be partitioned as either ROM or RAM. The ability to easily interchange data and work memory space makes the device ideal for a variety of different applications and programming requirements.
Fujitsu’s MB95R203A operates with power supplies ranging from 1.8 to 3.6V (1.8V power supplies are typically used in home healthcare devices, such as blood pressure and glucose meters.) It incorporates a full complement of timers and communication functions, as well as high-precision A/D converters, UART, I2C, and 16 I/O ports. The controller employs one-line on-chip debug, which requires only a single MCU pin. An embedded oscillator circuit maximises the number of pins available for use in smart meters, consumer appliances, electric tools, and other product designs.
The MB95R203A is shipped in 20-pin SOP packages. Samples are available now and production quantities will be ready by the end of November 2010. A comprehensive, user-friendly development toolkit is also available.
Advantages of Embedding FRAM
In addition to endurance, high-speed access, and low power consumption, FRAM incorporates anti-tampering protection to enhance data security. The high speed non-volatile nature of FRAM offers another unique advantage: it writes so fast that the MCU does not need to wait for the write operation to complete. This high-speed write operation allows data to be written quickly even if power is lost suddenly. When power is reinstated, the MCU can resume operations from the previous state. This capability is useful in applications where important data must be stored instantaneously and operations restored quickly following blackout periods.
In addition, programming code can be reduced, because there is no need to poll memory to complete a write operation, a process required by conventional memory. The operation is completed before polling takes effect. FRAM does not require code for wear levelling, which is common in Flash and E2PROM given their limited endurance cycles. The much longer endurance cycle of FRAM makes wear levelling redundant.