Product Overview
The CAT28LV256GI-25T from onsemi is a 256Kbit parallel nonvolatile SRAM organized as 32K x 8. 25ns access time with parallel address/data interface. Combines SRAM speed with EEPROM nonvolatility – stores data to EEPROM on power-down and restores on power-up. TSOP-28 industrial package.
Key Specifications
| Type | Parallel Nonvolatile SRAM |
| Density | 256 Kbit (32K x 8) |
| Access Time | 25 ns |
| Interface | Parallel (address + data bus) |
| Endurance | 1M write cycles |
| Data Retention | 100 years |
| Supply Voltage | 3.3V |
| Operating Temp | -40 to +85C (Industrial) |
| Package | TSOP-28 |
Working Principle
The CAT28LV256 integrates a 32Kx8 SRAM array with a shadow EEPROM array. During normal operation, reads and writes access the fast SRAM (25ns access time). When power failure is detected (via VCC monitor), the SRAM contents are automatically stored to the nonvolatile EEPROM array. On power-up, the EEPROM data is automatically recalled to the SRAM. The STORE and RECALL operations can also be triggered manually via pin or software commands. The SRAM provides unlimited read/write endurance; the EEPROM supports 1M store cycles with 100-year data retention.
Applications
- Parameter storage
- Configuration memory
- Auto-save on power loss
- Industrial data logging