Panasonic’s MCUs with resistive RAM, now in distribution

May 13, 2014 // By Graham Prophet
Mouser Electronics has the MN101L 8-bit Microcontrollers from Panasonic, the first microcontrollers with internal Resistive RAM (ReRAM). Resistive RAM is a new non-volatile embedded memory that offers five times the write performance of Flash or EEPROM memory without the need for an erase cycle. This has the benefit of offering high-speed non-volatile writing and longer operational times in battery powered devices.

Panasonic's Resistive RAM is based on a cell structure where a binary "1" and "0" is read based on the resistance of a thin-film metal oxide (tantalum oxide) sandwiched between two electrodes on the top and bottom of the metal oxide. The state of the memory cell is changed to a "1" by applying a pulsed negative voltage to the top electrode. This causes oxygen ions to migrate into the tantalum oxide, lowering the resistance and making the cell conductive to electricity. The state of the cell is changed to a "0" by applying a pulsed positive voltage to the top electrode. This causes oxygen ions to migrate away from the tantalum oxide, raising the resistance and making the cell non-conductive. The simple structure of a metal oxide stacked vertically between two electrodes results in excellent low power consumption and high-speed rewriting characteristics.

These Panasonic 8-bit MCUs have a total of 64 kBytes of ReRAM. 62 kBytes is used in the program memory area and is used in a similar way to conventional Flash memory. 2 kBytes of ReRAM is used in the data memory area and is used in a similar manner to EEPROM. ReRAM requires a write voltage of only 1.8V. Program Memory ReRAM has an endurance of 1K write cycles while ReRAM used as data memory is rated at up to 100K write cycles. Data retention is 10 years.

The Panasonic MN101L uses a simple 10 MHz 8-bit MCU core with a three-stage pipeline. It includes a 16x16 multiply, 32/16 divide, Real Time Clock (RTC), ADC, and an LCD controller. The Panasonic MN101L Series Evaluation Board, also available from Mouser Electronics, helps developers evaluate the MN101L and test Panasonic's new ReRAM technology.

Mouser; www.mouser.com/new/panasonic/panasonic-mn101l-reram/