PEDR45V256A-05 Issue Date: Oct. 17, 2011 MR45V256A 256k(32,768-Word 8-Bit) FeRAM (Ferroelectric Random Access Memory) SPI GENERAL DESCRIPTION The MR45V256A is a nonvolatile 32,768-word x 8-bit ferroelectric random access memory (FeRAM) developed in the ferroelectric process and silicon-gate CMOS technology. The MR45V256A is accessed using Serial Peripheral Interface.Unlike SRAMs, this device, whose cells are nonvolatile, eliminates battery backup required to hold data. This device has no mechanisms of erasing and programming memory cells and blocks, such as those used for various EEPROMs. Therefore, the write cycle time can be equal to the read cycle time and the power consumption during a write can be reduced significantly. The MR45V256A can be used in various applications, because the device is guaranteed for the write/read 12 tolerance of 10 cycles per bit and the rewrite count can be extended significantly. FEATURES 32,768-word 8-bit configuration (Serial Peripheral Interface : SPI) A single 3.3 V 0.3 V power supply Operating frequency: 15MHz 12 Read/write tolerance 10 cycles/bit Data retention 10 years Guaranteed operating temperature range 40 to 85C (Extended temperature version) Package options: 8-pin plastic SOP (P-SOP8-200-1.27-T2K ) 1/20 MR45V256A PEDR45V256A-05 MR45V256A PIN CONFIGURATION 8-pin plastic SOP VCC CS 1 8 SO HOLD 2 7 SCK WP 3 6 VSS4 5 SI Note: Signal names that end with indicate that the signals are negative-true logic. 2/20