Data scrambling in memory devices

Apparatus for data storage, comprising:

• an interface, which is configured to communicate with a memory device;
• and a processor, which is configured to;
• encode data for storage in the memory device with an Error Correction Code (ECC);
• encode a scrambling seed with the ECC;
• scramble the encoded data for storage in the memory device dependent upon the encoded scrambling seed;
• determine a statistical distribution of the scrambled encoded data;
• compute a measure of randomness of the scrambled encoded data dependent upon the determined statistical distribution;
• modify, a scrambling configuration of the scrambled encoded data dependent upon the computed measure of randomness of the scrambled data;
• store the scrambled encoded data having the modified scrambling configuration in the memory device.

A computer-accessible non-transitory storage medium having program instructions stored therein that, in response to execution by a computer system, cause the computer system to perform operations including:

• receiving, from a host, data to be stored in a memory device;
• encoding the received data with an Error Correction Code (ECC);
• initializing a scrambling seed;
• encoding the scrambling seed with the ECC;
• scrambling the encoded data dependent upon the encoded scrambling seed;
• determining a statistical distribution of the scrambled encoded data;
• computing a measure of randomness of the scrambled encoded data dependent upon the statistical distribution;
• modifying the encoded scrambling seed dependent upon the computed measure of randomness;
• re-scrambling the encoded data dependent upon the modified encoded scrambling seed;
• and storing the re-scrambled encoded data into the memory device;
• wherein scrambling the encoded data comprises:
• encoding two or more candidate scrambling seeds with the ECC;
• scrambling the encoded data with each of the two or more encoded candidate scrambling seeds, to create a respective two or more scrambled encoded data;
• wherein computing the measure of randomness comprises computing a respective level of randomness for each of the respective two or more scrambled encoded data;
• and wherein modifying the scrambling configuration comprises selecting one of the respective two or more scrambled encoded data dependent upon the respective levels of randomness.