A non-volatile memory device capable of reading and writing a large number of memory cells with multiple read/write circuits in parallel has an architecture that reduces redundancy in the multiple read/write circuits to a minimum. The multiple read/write circuits are organized into a bank of similar stacks of components. Redundant circuits among each stack are factored out. In one aspect, a serial bus allows communication between components in each stack, thereby reducing the number of connections in a stack to a minimum. A bus controller sends control and timing signals to control the operation of the components and their interactions through the serial bus. In a preferred embodiment, the bus transactions of corresponding components in all the similar stacks are controlled simultaneously.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 10/254,919, filed Sep. 24, 2002 now U.S. Pat. No. 6,891,753, which application is incorporated herein in its entirety by this reference.
A non-volatile memory device capable of reading and writing a large number of memory cells with multiple read/write circuits in parallel has an architecture that reduces redundancy in the multiple read/write circuits to a minimum. The multiple read/write circuits are organized into a bank of similar stacks of components. Redundant circuits among each stack are factored out. In one aspect, a serial bus allows communication between components in each stack, thereby reducing the number of connections in a stack to a minimum. A bus controller sends control and timing signals to control the operation of the components and their interactions through the serial bus. In a preferred embodiment, the bus transactions of corresponding components in all the similar stacks are controlled simultaneously.
A non-volatile memory device capable of reading and writing a large number of memory cells with multiple read/write circuits in parallel has features to reduce power consumption during read, and program/verify operations. A read or program verify operation includes one or more sensing cycles relative to one or more demarcation threshold voltages to determine a memory state. In one aspect, selective memory cells among the group being sensed in parallel have their conduction currents turned off when they are determined to be in a state not relevant to the current sensing cycle. In another aspect, a power-consuming period is minimized by preemptively starting any operations that would prolong the period. In a program/verify operation cells not to be programmed have their bit lines charged up in the program phase. Power is saved when a set of these bit lines avoids re-charging at every passing of a program phase.
A non-volatile memory device capable of reading and writing a large number of memory cells with multiple read/write circuits in parallel has features to reduce power consumption during read, and program/verify operations. A read or program verify operation includes one or more sensing cycles relative to one or more demarcation threshold voltages to determine a memory state. In one aspect, selective memory cells among the group being sensed in parallel have their conduction currents turned off when they are determined to be in a state not relevant to the current sensing cycle. In another aspect, a power-consuming period is minimized by preemptively starting any operations that would prolong the period. In a program/verify operation cells not to be programmed have their bit lines charged up in the program phase. Power is saved when a set of these bit lines avoids re-charging at every passing of a program phase.