Patent ID: 9361221
Filing Date: 2016-06-07
CPC Classification: G06F

Claim Text:
1. A method of writing data in a storage system, the method comprising: performing a garbage collection operation, including re-writing data from one or more units of a storage medium to a first sequence of write units of the storage medium by: performing a coarse multi-bit write operation that partially programs each memory cell of a respective write unit with a plurality of bits, followed by a second multi-bit write operation that completes programming of each memory cell of the respective write unit with the plurality of bits; and performing a write operation in response to a host command, including writing data received from a computer system external to the storage system to a second sequence of write units of the storage medium by: performing a lower page write operation that partially programs each memory cell of a respective write unit with a single, respective lower page bit, followed by an upper page write operation that completes programming of each memory cell of the respective write unit with a respective upper page bit; wherein write operations in response to host commands are performed by performing respective lower page write operations followed by respective upper page write operations, and data writes performed in garbage collection operations comprise respective coarse multi-bit write operations followed by respective second multi-bit write operations that complete the programming of each memory cell to which data is written during the garbage collection operations.