Memory bank arrangement for stacked memory
View Patent ↗In a three-dimensional stacked memory having through electrodes, no optimal layer arrangement, bank arrangement, control methods have been established, and thus optimal methods are desired to be established. A stacked memory includes memory core layers, an interposer, and an IF chip. By stacking memory core layers having the same arrangement, it is possible to cope with both of no-parity operation and parity operation. Further, bank designation irrespective of the number of stacks of the memory core layers can be achieved by assignment of a row address and a bank address. Further, the IF chip has refresh counters for performing a refresh control of the stacked memory. This arrangement provides a stacked memory including stacked memory core layers having through electrodes.
1. A memory device
a plurality of memory core layers each including a plurality of through electrodes; and
an interface chip including a plurality of electrodes;
the memory core layers being stacked over the interlace chip with one another such that the through electrodes of a lower one of the memory core layers are connected respectively to the through electrodes of an upper one of the memory core layers and the through electrodes of a lowest one of the memory core layers are connected respectively to the through electrodes of the interface chip;
each of the memory core layers further including a plurality of memory banks each containing a plurality of memory cells;
the interface chip generating bank address information and supplying the bank address information in common to the memory core layers via the through electrodes to designate memory banks belonging respectively to the memory core layers;
the interface chip further generating row address information and supplying the row address information in common to the memory core layers via the through electrodes, the row address information comprising a more significant bit part and a less significant bit part, one or more bits belonging to the more significant bit part being allocated as layer selection information to select one of the memory core layers; and
the interface chip performing, in response at least to the less significant bit part of the row address information, a data read/write operation on a memory bank which is contained in the memory banks designated by the bank address information and which belongs to one of the memory core layers that is selected by the one or more bits belonging to the more significant bit part of the row address information.
2. The memory device according to claim 1 , wherein:
the memory device further comprises a parity layer which is the same structure as one of the memory core layers, wherein the parity layer and the memory core layers are stacked on each other;
wherein:
the parity layer includes a plurality of through electrodes which are connected respectively to the plurality of through electrodes of the memory core layers,
the parity layer further including a plurality of memory banks each containing a plurality of memory cells,
the interface chip supplying the bank address information in common to the memory core layers and the parity layer via the through electrodes to designate memory banks belonging respectively to the memory core layers and the parity layer,
the parity layer inverting a part of the bank address information and selecting one memory bank of the parity layer differing from the memory bank which the memory core layers selects,
wherein:
the one memory bank of the parity layer is designated by the bank address information which comprises the inverting of a part of the bank address information, and
the parity layer activates together with activation of selected ones of the memory core layers regardless of the more significant bit part of the row address information.
3. The memory device according to claim 2 , wherein
the memory banks of the parity layer each include a plurality of sub mats, and the sub mats are allocated to the more significant bit part of the row address information respectively.
4. The memory device according to claim 1 , wherein
each of the memory core layers further includes a programmable address decoder each programming a choice combination of the plurality of memory banks which the bank address information indicates.
5. The memory device according to claim 4 , wherein:
the programmable address decoder comprises a selector including a first and a second input nodes and including a logic gate which including a third and a fourth input nodes, wherein
the bank address information is supplied to the first input node,
an invalid address signal invalidating the bank address information is supplied to the second input node, the bank address information is supplied to the third input node,
an output node of the selector connects to the fourth input node.
6. The memory device according to claim 1 , wherein
each of the memory core layers comprises a comparator to compare with a layer address information which defines the memory core layers respectively and the more significant bit part of the row address information.
7. The memory device according to claim 6 , wherein
the comparator comprises a first logic gate and a second logical gate, wherein
the first logic gate compares the more significant bit part with the layer address information, and
the second logic gate is supplied with a mat selection signal selecting one of the plurality of memory banks and a signal of an output node of the first logic gate.
8. The memory device according to claim 1 , wherein:
the interface chip further comprises a plurality of refresh counters,
the plurality of memory banks in each of the memory core layers are defined by a plurality of refresh groups corresponding to a number of the plurality of refresh counters respectively, and
each of a refreshment of the plurality of refresh groups is controlled by each of the plurality of refresh counters.
9. The memory device according to claim 8 , wherein:
the memory device further comprises a parity layer which is the same structure as one of the memory core layers, the parity layer and the memory core layers are stacked on each other,
the parity layer comprises a plurality of memory banks,
the plurality of memory banks of the parity layer are defined by a plurality of refresh groups corresponding to the number of the plurality of refresh counters respectively, and
the plurality of refresh groups of the parity layer corresponds with the plurality of refresh groups of the memory core layers respectively.
10. The memory device according to claim 1 , wherein:
the memory core layers are assigned to plural groups which each contain the same number of the memory core layers and each contain at least more than one of the memory core layers,
the more significant bit part of the row address information containing plural bits,
the interface chip allocating part of the more significant bit in part of the row address information as part of the bank address information,
the interface chip selecting one of the memory bank which is contained in memory banks in one of the plural groups designated by the part of bank address information, and
the interface chip further selecting one of the plural groups by remaining part of the more significant bit part of the row address information.
11. The memory device according to claim 10 , wherein:
the memory device further comprises a parity layer which is of the same structure as one of the memory core layers, the parity layer and the memory core layers are stacked on each other,
wherein
the parity layer includes a plurality of through electrodes which are connected respectively to the plurality of through electrodes of the memory core layers,
parity layer further including a plurality of memory banks each containing a plurality of memory cells, the interface chip supplies the bank address information in common to the memory core layers and the parity layer via the through electrodes to designate memory banks belonging respectively to the memory core layers and the parity layer,
the parity layer inverting in a part of the bank address information and selecting one memory bank of the parity layer differing the memory bank which the memory core layers selects,
the one memory bank of the parity layer is designated by the bank address information which comprises the inverting in a part of the bank address information, and
the parity layer activates together in activity of selected one of the memory core layers regardless of the more significant bit part of the row address information.
12. The memory device according to claim 11 , wherein
the memory banks of the parity layer each including a plurality of sub mats, and
the sub mats are allocated the more significant bit part of the row address information respectively.
13. The memory device according to claim 10 , wherein
each of the memory core layers further including a programmable address decoder each programming a choice combination of the plurality of memory banks which the bank address information indicates.
14. The memory device according to claim 13 , wherein
the programmable address decoder comprises a selector including a first and a second input nodes and including a logic gate which including a third and a fourth input nodes,
the bank address information is supplied to the first input node,
an invalid address signal invalidating the bank address information is supplied to the second input node, the bank address information is supplied to the third input node, and
an output node of the selector connects to the fourth input node.
15. The memory device according to claim 10 , wherein
each of the memory core layers comprises a comparator to compare with a layer address information which defines the memory core layers respectively and the more significant bit part of the row address information.
16. The memory device according to claim 15 , wherein:
the comparator comprises a first logic gate and a second logical gate,
the first logic gate compares the more significant bit part with the layer address information, and
the second logic gate is supplied with a mat selection signal selecting one of the plurality of memory banks and a signal of an output node of the first logic gate.
17. The memory device according to claim 10 , wherein:
the interface chip further comprises a plurality of refresh counters,
the plurality of memory banks in each of the memory core layers are defined by a plurality of refresh groups corresponding to a number of the plurality of refresh counters respectively,
each of a refreshment of the plurality of refresh groups is controlled by each of the plurality of refresh counters.
18. The memory device according to claim 17 , wherein
the memory device further comprises a parity layer which is same structure as one of the memory core layers,
the parity layer and the memory core layers are stacked on each other,
the parity layer comprises a plurality of memory banks,
the plurality of memory banks of the parity layer are defined by a plurality of refresh groups
corresponding to the number of the plurality of refresh counters respectively, and
the plurality of refresh groups of the parity layer corresponds with the plurality of refresh groups of the memory core layers respectively.