IS23SC4442

IS23SC4442 256 BYTE EEPROM WITH WRITE PROTECT FUNCTION AND PROGRAMMABLE SECURITY FEATURES Standard CMOS process 256 x 8 bits EEPROM organization Byte-wise addressing Irreversible byte-wise write protection of lowest 32 address (Byte 0..31) 3-byte Programmable Security Code (PSC) for memory write/erase protection 2.7-5.5V power supply for read and write/erase Low power operation: 3 mA typical active current 2.5 ms programming time 2-wire serial interface www.DataSheet4U.com ISSI PRELIMINARY INFORMATION August 2003 ® DESCRIPTION IS23SC4442 contains 256 x 8 bits of EEPROM main memory and a 32 x 1 bit protection PROM memory. The main memory can be randomly accessed byte by byte. During memory erase, all 8 bits of a byte are set to logical one. During memory write, individual bit(s) are set to logical zeros depend on the data value to be written. Normally, a data change may consists of an erase and a write operation. The write or erase operation takes at least 2.5 ms to complete. The first 32 bytes (Address: 0 to 31) in memory are irreversibly protected by the corresponding 32 protect bits in the 32 x 1 bit protection memory. The 32 protect bits are onetime programmable, and they cannot be erased once they are set to logical zero. IS23SC4442 provides a 3-bit Error Counter (EC), and three bytes Programmable Security Code (PSC) to prevent unauthorized erase/write operation to the memory. All the memory, except the PSC, can be read after the chip is powered on. B...