Page buffer block and memory device including the same
A memory device according to an embodiment includes a memory cell array including a plurality of memory cells, a control logic configured to control a verification operation for the plurality of memory cells, a page buffer block including a plurality of page buffers connected to the memory cell array through bit lines, a page buffer decoder that outputs, through an output line. a verification signal generated from at least one of outputs of the plurality of page buffers by a verification operation, and a verification error removal circuit connected to the output line and configured to control an output path of the verification signal to the control logic.
1 . A memory device comprising:
a memory cell array including a plurality of memory cells;
a control logic configured to control a verification operation for the plurality of memory cells; and
a page buffer block including a plurality of page buffers connected to the memory cell array through bit lines, a page buffer decoder that outputs, through an output line, a verification signal generated from at least one of outputs of the plurality of page buffers by the verification operation, and a verification error removal circuit connected to the output line and configured to control an output path of the verification signal to the control logic,
wherein the verification error removal circuit includes a first latch configured to store state information indicating whether at least one bit line or at least one page buffer related to the verification signal is defective, and is configured to control the output path, based on an output of the first latch and a path control signal generated from the verification signal.
2 . The memory device of claim 1 , wherein a low level of the state information indicates a defective state and a high level of the state information indicates a normal state.
3 . The memory device of claim 1 , wherein the output line is used to transfer state information to the first latch.
4 . The memory device of claim 1 , wherein the verification error removal circuit is configured to disable the output path, based on the path control signal, when the output line includes a stuck defect at a high level, and to disable the output path, based on the output of the first latch, when the output line includes a stuck defect at a low level.
5 . The memory device of claim 1 , wherein the verification error removal circuit is configured to disable the output path, based on the output of the first latch, when the state information indicates that the at least one bit line or the at least one page buffer is defective.
6 . The memory device of claim 1 , wherein the control logic is configured to perform an off-cell count operation on the plurality of memory cells, based on the verification signal.
7 . The memory device of claim 1 , wherein the verification error removal circuit includes:
an inverter configured to invert the verification signal received through the output line and output the inverted verification signal as the path control signal;
a first n-type transistor configured to receive the path control signal through a gate terminal; and
a second n-type transistor configured to receive an output of the first latch through a gate terminal,
wherein the first n-type transistor and the second n-type transistor comprise a part of the output path.
8 . The memory device of claim 7 , wherein the verification error removal circuit further includes:
a third n-type transistor configured to reset the first latch; and
a fourth n-type transistor and a fifth n-type transistor coupled to each other in a cascade manner to store the state information in the first latch.
9 . The memory device of claim 8 , wherein the third n-type transistor is configured to receive a reset signal through a gate terminal,
the fourth n-type transistor is configured to receive a set signal through a gate terminal, and
the fifth n-type transistor is configured to receive the path control signal through a gate terminal.
10 . The memory device of claim 7 , wherein the verification error removal circuit is further configured to include a sixth n-type transistor configured to transfer the output of the first latch received through a drain terminal in a test period of the first latch, to the output line through a source terminal.
11 . The memory device of claim 1 , wherein the verification error removal circuit further includes a second latch configured to store the state information before the state information is stored in the first latch.
12 . The memory device of claim 11 , wherein the state information is transferred from the second latch to the first latch through the output line.
13 . The memory device of claim 1 , wherein the verification error removal circuit is configured to enable or disable the output path based on the path control signal and the output of the first latch.
14 . The memory device of claim 1 , wherein the plurality of memory cells include vertically stacked nonvolatile memory cells.
15 . A page buffer block comprising:
a plurality of page buffers connected to a memory cell array through bit lines;
a page buffer decoder configured to output, through an output line, a verification signal generated by selecting at least one output from the plurality of page buffers; and
a verification error removal circuit connected to the output line and configured to control enabling or disabling of an output path of the verification signal,
wherein the verification error removal circuit includes a first latch configured to store state information indicating whether at least one bit line or at least one page buffer related to the verification signal is defective, and is configured to control the output path the state information and a path control signal generated from the verification signal.
16 . The page buffer block of claim 15 , wherein the verification error removal circuit includes:
an inverter configured to invert the verification signal received through the output line and output the inverted verification signal as the path control signal;
a first n-type transistor configured to receive the path control signal through a gate terminal; and
a second n-type transistor configured to receive an output of the first latch through a gate terminal,
wherein the first n-type transistor and the second n-type transistor comprise a part of the output path.
17 . The page buffer block of claim 16 , wherein the second n-type transistor is configured to be turned off in response to an output of the first latch at a low level, when the state information has a low level indicating a defective state.
18 . The page buffer block of claim 16 , wherein the first n-type transistor is configured to be turned off in response to the path control signal at a low level, when the output line includes a stuck defect at a high level.
19 . The page buffer block of claim 16 , wherein the output line is used to transfer the state information to the first latch.
20 . The page buffer block of claim 16 , wherein the verification error removal circuit further includes a second latch configured to store the state information before the state information is stored in the first latch,
wherein the state information is transferred from the second latch to the first latch through the output line.