DESCRIPTION
This specification covers a range of 4K bit serial EEPROM products, the ST93C66 specified at 5V ± 10% and the ST93C67 specified at 3V to 5.5V. In the text, products are referred to as ST93C66.
The ST93C66 is a 4K bit Electrically Erasable ProgrammableMemory(EEPROM) fabricatedwith SGS-THOMSON’s High EnduranceSingle Polysilicon CMOS technology. The memory is accessed through a serial input (D) and output (Q). The 4K bit memory is divided into either 512 x 8 bit bytes or 256 x 16 bit words. The organization may be selected by a signal applied on the ORG input.

■ 1 MILLION ERASE/WRITE CYCLES, with 40 YEARS DATA RETENTION
■ DUAL ORGANIZATION: 256 x 16 or 512 x 8
■ BYTE/WORD and ENTIRE MEMORY PROGRAMMING INSTRUCTIONS
■ SELF-TIMED PROGRAMMING CYCLE with AUTO-ERASE
■ READY/BUSY SIGNAL DURING PROGRAMMING
■ SINGLE SUPPLY VOLTAGE:
   – 4.5V to 5.5V for ST93C66 version
   – 3V to 5.5V for ST93C67 version
■ SEQUENTIAL READ OPERATION
■ 5ms TYPICAL PROGRAMMING TIME
■ ST93C66 and ST93C67 are replaced by the M93C66