Apparatus and method of page program operation for memory devices with mirror back-up of data
View Patent ↗An apparatus and method of page program operation is provided. When performing a page program operation with a selected memory device, a memory controller loads the data into the page buffer of one selected memory device and also into the page buffer of another selected memory device in order to store a back-up copy of the data. In the event that the data is not successfully programmed into the memory cells of the one selected memory device, then the memory controller recovers the data from the page buffer of the other memory device. Since a copy of the data is stored in the page buffer of the other memory device, the memory controller does not need to locally store the data in its data storage elements.
1. An apparatus for controlling a plurality of memory devices interconnected in-series, each of the memory devices having a page buffer and memory cells, the apparatus comprising:
a data processor configured
to execute a page program operation with a mirror back-up of data by:
writing data to the page buffer of a selected memory device of the plurality of memory devices and to the page buffer of another memory device of the plurality of memory devices;
instructing the selected memory device to program the data loaded in its page buffer into its memory cells; and
determining whether the data is not successfully programmed into the memory cells of the selected memory device, recover the data from the page buffer of the another memory device,
to recover the data from the page buffer of the another memory device by:
reading back the data from the page buffer of the another memory device without programming the data into the memory cells of the another memory device,
to transmit a single command for writing the data to both the page buffer of the selected memory device and the page buffer of the another memory device,
to write the data to both the page buffer of the selected memory device and the page buffer of the another memory device by:
broadcasting a first message to inform all of the memory devices to enter a multi-address detection mode in which the another memory device will process commands addressed to the selected memory device;
sending the single command for writing the data to both the page buffer of the selected memory device and the page buffer of the another memory device; and
broadcasting a second message to inform all of the memory devices to exit the multi-address detection mode.
2. The apparatus of claim 1 further comprising:
data storage for storing the data prior to writing the data to the page buffer of the selected memory device and to the page buffer of the another memory device;
the apparatus being further configured to free up space in the data storage where the data is stored before determining whether the data has been successfully programmed into the memory cells of the selected memory device.
3. The apparatus of claim 2 wherein the data processing unit is configured to execute another operation before determining whether the data has been successfully programmed into the memory cells of the selected memory device.
4. The apparatus of claim 1 further comprising:
an output connection for connecting with a first memory device of the plurality of memory devices; and
an input connection for connection with a last memory device of the plurality of memory devices.
5. The apparatus of claim 4 wherein:
the data processor is configured to write the data to the page buffer of the selected memory device and to the page buffer of the another memory device by transmitting the data over the output connection; and
the data processor is configured to recover the data from the page buffer of the another memory device by transmitting a read command over the output connection and receiving the data over the input connection in response to the read command.
6. The apparatus of claim 4 wherein the data processor is configured to determine whether the data has been successfully programmed into the memory cells of the selected memory device by:
transmitting a read status command over the output connection and receiving a program status from the page buffer of the selected memory device over the input connection in response to the read status command; and
determining based on the program status whether the data has been successfully programmed into the memory cells of the selected memory device.
7. The apparatus of claim 2 wherein the data processor is configured to execute at least one of:
upon recovering the data, re-attempt to program the data into the memory cells of the selected memory device but at a different address;
upon recovering the data, attempt to program the data into the memory cells of another selected memory device; and
upon recovering the data, store the data back in the data storage.
8. The apparatus of claim 1 wherein the data processor is configured to transmit a first command addressed to the selected memory device for writing the data to the page buffer of the selected memory device, and to transmit a second command addressed to the another memory device for writing the data to the page buffer of the another memory device.
9. The apparatus of claim 1 wherein:
the first message is a write link configuration register command; and
the second message is a write link configuration register command.
10. A memory device for use as one of a set of memory devices connected in-series, the memory device comprising:
an input connection;
an output connection;
an identification of a device address of the memory device; and
a device controller configured to:
receive messages to enter and exit a multi-address detection mode, and enter and exit the multi-address detection mode accordingly;
receive a command over the input connection, the command comprising a device address;
while not in the multi-address detection mode, process the command only if the device address of the command matches the device address of the device; and
while in the multi-address detection mode: i) process the command if the device address of the command is the same as the device address of the device and ii) process the command if the device address of the command is the same as the device address of at least one other predetermined device.
11. The memory device of claim 10 wherein:
the device controller receives messages to enter and exit the multi-address detection mode by receiving write link configuration register commands.
12. The memory device of claim 10 wherein the device address of the at least one predetermined device comprises any device address that differs from the device address of a the given device in a predefined manner.
13. The memory device of claim 12 wherein said predefined manner is determined only by a single predefined bit.
14. The memory device of claim 13 wherein the single predefined bit is a least significant bit.
15. The memory device of claim 10 wherein:
the memory device further comprises a page buffer and memory cells;
the command further comprises data;
the command is for loading the data into the page buffer; and
the device controller is configured to process the command by loading the data into the page buffer.
16. A method in a memory device forming part of a set of memory devices connected in-series, the method comprising:
maintaining a device address;
receiving messages to enter and exit a multi-address detection mode;
receiving a command comprising a device address;
while not in the multi-address detection mode, processing the command only if a destination address matches the device address; and
while in the multi-address detection mode:
processing the command if the device address of the command is the same as the device address of the device; and
processing the command if the device address of the command is the same as the device address of at least one other predetermined device.