Flash memory device with data output control
View Patent ↗An apparatus, system, and computer-implemented method for controlling data transfer between a plurality of serial data link interfaces and a plurality of memory banks in a semiconductor memory is disclosed. In one example, a flash memory device with multiple links and memory banks, where the links are independent of the banks, is disclosed. The flash memory devices may be cascaded in a daisy-chain configuration using echo signal lines to serially communicate between memory devices. In addition, a virtual multiple link configuration is described wherein a single link is used to emulate multiple links.
1. A memory device comprising:
flash memory;
read circuitry configured to obtain read data from said flash memory to facilitate subsequent transmission of the read data;
an output buffer configured to receive the read data and to transmit the read data through an output port in response to an output enable signal, the output enable signal being held at a logic level for a period of time that delineates a length of said data transmitted from said output port;
a clock input configured to receive a clock signal having edges; and
additional circuitry configured to clock out the read data from said output port in tandem with said edges for a duration of time corresponding to the period of time the output enable signal is held at the logic level.
2. The memory device as in claim 1 , wherein the output buffer transmits the read data through the output port at a predetermined delay after the output enable signal is driven to the logic level.
3. The memory device as in claim 1 further comprising:
a first input port configured to receive command information; and
a second input port configured to receive an input enable signal that indicates a beginning of a command data stream that contains said command information by way of a transition from an inactive state to the active state.
4. The memory device as in claim 3 , wherein said command data stream includes a serial data stream.
5. The memory device as in claim 1 , wherein said read data includes a serial data stream.
6. A memory device comprising:
flash memory;
read circuitry configured to obtain read data from said flash memory to facilitate subsequent transmission of the read data;
an output buffer configured to receive the read data and to transmit the read data through an output port in response to an output enable signal, said read data transmitted from said output port including a first data stream and a second data stream, the first data stream being delineated from the second data stream based on a logic level of said output enable signal, the output enable signal being held at a logic level for a period of time that delineates a length of the first data stream and the second data stream transmitted from said output port.
7. The memory device as in claim 6 further comprising:
a first input port configured to receive command information; and
a second input port configured to receive an input enable signal that indicates a beginning of a command data stream that contains said command information by way of a transition from an inactive state to the active state.
8. The memory device as in claim 7 , wherein said command data stream includes a serial data stream.
9. The memory device as in claim 6 , wherein said read data includes a serial data stream.
10. The memory device as in claim 6 , wherein the output buffer transmits the read data through the output port at a predetermined delay after the output enable signal is driven to the logic level.
11. A method for providing a data stream comprising:
driving an output enable signal to an active state for a period of time, the period of time substantially corresponding to a number of bits of data to sequentially appear at an output port of a flash memory device, the number of bits being up to a page buffer in size;
transmitting the number of bits of data from the output port for the period of time;
receiving a free-running clock having inactive to active and active to inactive transitions; and
transmitting one bit of the data from the output port on each of the inactive to active transitions of the free-running clock during the period of time.
12. The method as in claim 11 further comprising:
receiving an input enable signal transitioning from an inactive state to the active state that indicates a beginning of a command data stream that contains command information; and
receiving said command data stream.
13. The method as in claim 12 , wherein the command information includes a read command.
14. The method as in claim 12 , wherein the command information includes a read address.
15. The method as in claim 12 , wherein bits of the command data stream are received on each of the inactive to active transitions of the free running clock while the input enable signal is in the active state.
16. A method for providing a data stream comprising:
driving an output enable signal to an active state for a period of time, the period of time substantially corresponding to a number of bits of data to sequentially appear at an output port of a flash memory device, the number of bits being up to a page buffer in size;
transmitting the number of bits of data from the output port for the period of time where a first bit of the data is provided within a first clock period while the output enable signal is driven to the active state within the first clock period, and a last bit of the data is provided within a second clock period while the output enable signal is driven to an inactive state within the second clock period.
17. The method as in claim 16 further comprising:
receiving an input enable signal transitioning from an inactive state to the active state that indicates a beginning of a command data stream that contains command information; and
receiving said command data stream.
18. The method as in claim 17 , wherein the command information includes a read command.
19. The method as in claim 17 , wherein the command information includes a read address.
20. The method as in claim 17 , wherein bits of the command data stream are received on each inactive to active transition of a clock while the input enable signal is in the active state.
21. A memory system comprising:
a controller; and
a number of memory devices, each of the memory devices including
flash memory;
a clock input configured to receive a clock signal having edges,
read circuitry configured to obtain read data from said flash memory to facilitate subsequent transmission of the read data;
an output buffer configured to receive the read data and to transmit the read data through an output port in response to an output enable signal, the output enable signal being held at a logic level for a period of time that delineates a length of said read data transmitted from said output port; and
additional circuitry configured to clock out the read data from said output buffer in tandem with said edges for a duration of time corresponding to the period of time the output enable signal is held at the logic level.
22. The memory system device as in claim 21 wherein each of said memory devices further includes a first input port configured to receive command information, and a second input port configured to receive an input enable signal that indicates a beginning of a command data stream that contains said command information by way of a transition from an inactive state to an active state.
23. The memory system as in claim 21 , wherein the output buffer transmits the read data through the output port at a predetermined delay after the output enable signal is driven to the logic level.
24. A method for providing a data stream comprising:
driving an output enable signal to an active state for a period of time, the period of time substantially corresponding to a number of bits of data to sequentially appear at an output port of a flash memory device, the number of bits being up to a page buffer in size; and
transmitting the number of bits of data from the output port for the period of time, a first bit of the data is provided at a first predetermined delay after the output enable signal is driven to the active state, and a last bit of the data is provided at a second predetermined delay after the output enable signal is driven to an inactive state.
25. The method as in claim 24 further comprising:
receiving an input enable signal transitioning from an inactive state to the active state that indicates a beginning of a command data stream that contains command information; and
receiving said command data stream.
26. The method as in claim 25 , wherein the command information includes a read command.
27. The method as in claim 25 , wherein the command information includes a read address.
28. The method as in claim 25 , wherein bits of the command data stream are received on each inactive to active transition of a clock while the input enable signal is in the active state.