The main features of the SLE4428 are:
- Synchronous communication protocol, ISO 7816 compatible

100% functional compatibility to SLE 5528
1024 x 8 bit EEPROM organization of Data Memory
1024 x 1 bit Protection Memory
Byte-wise write protection of Data Memory (one time programmable)
Not alterable Manufacturer Code (chip coding and unique coding by application identifier RID according to ISO/IEC 7816-5)

Data Memory alterable only after verification of 2 Byte PSC
PSC verification trials limited by Error Counter
Serial synchronous three-wire link protocol according to ISO/IEC 7816
Byte-wise addressing
End of processing indicated at data output
Contact configuration and Answer-to-Reset (synchronous transmission) in accordance to standard ISO/IEC 7816