Solid state storage device and error correction method thereof

A solid state storage device in communication with a host, the solid state storage device comprising:

• a controller in communication with the host, wherein the controller comprises a soft decoder;
• a flash memory connected to the controller and receiving plural slicing voltages from the controller, wherein the flash memory issues a soft data according to the plural slicing voltages;
• and
• a buffer connected to the controller,
• wherein the soft decoder performs an error correction process of the soft data according to a predetermined log-likelihood ratio (LLR) parameter set, wherein if the error correction process of the soft data is not successfully completed according to the predetermined LLR parameter set, the controller selects another LLR parameter set from a LLR table and the soft decoder performs the error correction process of the soft data according to the selected LLR parameter set.