SLE 4442 provides a security code logic which controls the write/erase access to the memory. For this purpose the SLE 4442 contains a 4-byte security memory with an Error Counter EC (bit 0 to bit 2) and 3 bytes reference data. These 3 bytes as a whole are called Programmable Security Code (PSC). After power on the whole memory, except for the reference data, can only be read. Only after a successful comparison of verification data with the internal reference data the memory has the identical access functionality of the SLE 4432 until the power is switched off. After three successive unsuccessful comparisons the Error Counter blocks any subsequent attempt and hence any possibility to write and erase.
SLE4442 chip upgrade product is SLE5542, the function and feature of both chip is exactly same.
The chip completely compatible with SLE4442 is FM4442. The performance of FM4442 is the same as SLE4442 chip. As the price of SLE4442 is relatively higher, so the FM4442 is used in many projects instead of SLE4442 chip.
