发明名称 Non-volatile memory with erase verify circuit having comparators indicating under-erasure, erasure, and over-erasure of memory cells
摘要 A memory device verify system determines a state of memory cells in a memory. The memory includes a memory array having a plurality of memory cells coupled to bit lines. A verify circuit is coupled to the bit lines to determine if memory cells have a erase level that is within predetermined upper and lower limits. The verify circuit can include first and second comparators. In one embodiment, the first comparator is used to compare a bit line current with an upper first reference current. The second comparator is used to compare a bit line current with a lower second reference current. The comparator circuit is not limited to reference currents, but can use reference voltages to compare to a bit line voltage. The verify circuit, therefore, eliminates the need for separate bit line leakage testing to identify over-erased memory cells.
申请公布号 US7196934(B2) 申请公布日期 2007.03.27
申请号 US20060400993 申请日期 2006.04.10
申请人 发明人
分类号 G11C16/34 主分类号 G11C16/34
代理机构 代理人
主权项
地址