Is ECC feature in DDR realized with using Hamming code technique?
The ECC is not performed on an individual byte basis.
Usually, 8 bytes are combined with one parity bit per byte. Giving a total of 72 bits.
Since only 7 parity bits are needed to correct single-bit errors and 8 are available the extra bit can be used to detect double bit errors, although not correct the error.
Hamming code
Hamming Codes With Additional Parity