The main features of the SLE5542 are:

SLE 5542 256byte encryption card, can read data, write data, protect data and write password,
lower cost with higher intergrated technology that protect your access control and passwords
protection.

• SLE 5542 , Intelligent 256-Byte EEPROM with Write Protection function and Programmable
  Security Code
• SLE 5542 replaces SLE 4442
• SLE 5542 is 100% functional compatible to SLE 4442
• 256 x 8-bit EEPROM organization of Data Memory
• 32 x 1-bit Protection Memory