Description
The U631H64 has two separate modes of operation: SRAM mode and nonvolatile mode. In SRAM mode, the memory operates as an ordinary static RAM. In nonvolatile operation, data is transferred in parallel from SRAM to EEPROM or from EEPROM to SRAM. In this mode SRAM functions are disabled.

Features
• High-performance CMOS nonvolatile static RAM 8192 x 8 bits
• 25, 35 and 45 ns Access Times
• 12, 20 and 25 ns Output Enable Access Times
• Software STORE Initiation (STORE Cycle Time < 10 ms)
• Automatic STORE Timing
• 105 STORE cycles to EEPROM
• 10 years data retention in EEPROM
• Automatic RECALL on Power Up
• Software RECALL Initiation (RECALL Cycle Time < 20 μs)
• Unlimited RECALL cycles from EEPROM
• Unlimited Read and Write to SRAM
• Single 5 V ± 10 % Operation
• Operating temperature ranges:
    0 to 70 °C
    -40 to 85 °C
• QS 9000 Quality Standard
• ESD characterization according MIL STD 883C M3015.7-HBM (classification see IC Code Numbers)
• RoHS compliance and Pb- free
• Packages: PDIP28 (300 mil)
                    SOP28 (330 mil)