Non-volatile storage system with power on read timing reduction

Abstract

Technology is disclosed herein for loading redundancy information during a memory system power on read (POR). A memory structure has primary regions (e.g., primary columns) and a number of redundant regions (e.g., redundant columns). The status of the regions is stored in isolation latches during the POR. Initially, simultaneously all latches for primary regions are reset to used and all latches for redundant regions are reset to unused. Then, isolation latches for defective primary regions are set to unused while isolation latches for corresponding redundant regions are set to used. There is no need to individually set isolation latches for redundant regions to unused, which saves time during POR. Moreover, whenever the isolation latch for a defective primary region is set from used to unused, in parallel the isolation latch for the replacement redundant column may be set from unused to used, thereby not incurring a time penalty.