บัตร Smart card SLE-4428 1 KB Memory
IS23SC4428 offers all the features in IS23SC4418. In addition, it offers two bytes of Programmable Security Code (PSC)
against unauthorized memory write/erase operations. All the memory, except for the PSC can always be read, but the memory
can be written or erased only after PSC verification. If the user fails to enter the correct PSC in eight consecutive attempts,
the device will block any further PSC entry attempts and the memory can never be erased or written again. The PSC bytes
are pre-programmed by the manufacturer with a code, which is specified for the customer for device transport security
purposes, before the devices are shipped to the customer. The Error Counter will be pre-erased by the manufacturer to allow
maximum attempts (maximum of eight) for PSC entry.