Semiconductor storage device and method of reading data therefrom
A semiconductor memory device includes a first memory cell array having a first plane which is composed of a plurality of blocks each having a plurality of memory cells, a sense circuit which reads data the memory cells, a sequencer which receives control signals from outside, a first address register, and a second address register which receives an output address from the first address register and outputs an address signal in response to an address control signal from the sequencer. In reading from the memory cells, the sequencer reads a page n in accordance with the address stored in the second address register, then transfers an address stored in the first address register to the second address register concurrently with outputting data read from the page n to outside and reads data from an arbitrary page m in accordance with the address transferred to the second address register.
1. A semiconductor memory device comprising:
a first memory cell array having a first plane and a second plane each of which is composed of a plurality of blocks each having a plurality of memory cells arranged in a matrix form at intersections of bit lines and word lines;
a sense circuit including data cache;
a sequencer which receives a control signal from outside; and
an IO buffer which receives a first address of the first plane and a second address of the second plane from outside,
wherein the sequencer, in reading from the memory cells, reads a page n in accordance with the first address, then reads data from an arbitrary page m in accordance with the second address concurrently with outputting data read from the page n to outside.
2. The device according to claim 1 , further comprising:
a first address register which receives the first address and second address from the IO buffer; and
a second address register which receives the first address from the first address register and outputs an address signal in response to an address control signal from the sequencer.
3. The device according to claim 2 , wherein the first address register is provided with a first page address register having its input connected to receive a page address, a first block address register having its input connected to receive a block address, a second block address register having its input connected to the output of the first block address register, and a third block address register having its input connected to the output of the first block address register.
4. The device according to claim 3 , wherein the second address register is provided with a first internal address register having its input connected to the output of the first page address register, a second internal address register having its input connected to the output of the second block address register, and a third internal address register having its input connected to the output of the third block address register.
5. The device according to claim 1 , wherein each of the blocks has a plurality of pages which are arranged along the word lines and each of which is composed of a data area and a redundant area.
6. The device according to claim 5 , wherein user data and management data stored in the pages reside scattered across the blocks of the first and second planes.
7. The device according to claim 1 , wherein the IO buffer receives a cache read command after receiving the first address and before receiving the second address.
8. The device according to claim 1 , further comprising a control buffer which receives, amplifies and holds the control signal.
9. The device according to claim 8 , further comprising a command decoder which decodes a command input from the control buffer to send it to the sequencer.
10. The device according to claim 1 , wherein the first memory cell array is a NAND flash memory.