FLASH MEMORY CONTROLLER CONTROLLING VARIOUS FLASH MEMORY CELLS

• US 20080086631A1
• Filed: 09/28/2007
• Published: 04/10/2008
• Est. Priority Date: 01/06/2000
• Status: Active Grant

• Current Assignee: Super Talent Technology, Corporation
• Original Assignee: Super Talent Electronics, Inc.
• Inventors: Lee, Edward, Lee, Charles, Chow, David, Shen, Ming-Shiang, Yu, Frank
• Granted Patent: US 7,676,640 B2
• Time in Patent Office: Days
• US Class Current: 713/2
• CPC Class Codes: G06F 8/654 using techniques specially adapted for alterable solid state memories, e.g. for EEPROM or flash memories

Abstract

An electronic data flash card is accessible by a host system, and includes a flash memory controller and at least one flash memory device coupled to the flash controller. The boot code and control code for the flash memory system (flash card) are stored in the flash memory device during a programming procedure. The flash controller transfers the boot code and control code to a volatile main memory (e.g., random access memory or RAM) at start up or reset making a RAM-based memory system. Boot code and control code are selectively overwritten during a code updating operation. A single flash controller thus supports multiple brands and types of flash memory to eliminate stocking issues.

Claims

1. An electronic data flash card adapted to be accessed by a host system that is capable of establishing a communication link, said electronic data flash card comprising:

(A) a card body;

(B) a flash memory device mounted on the card body, the flash memory device including a plurality of non-volatile memory cells, including a first block for storing a pointer pointing to a second block having predetermined non-volatile memory cells;

(C) an input/output interface circuit mounted on the card body for establishing communication with the host system; and

(D) a flash memory controller mounted on the card body and electrically connected to said flash memory device and said input/output interface circuit, wherein the flash memory controller comprises means for selectively operating in one of;

a programming mode in which said flash memory controller activates said input/output interface circuit to receive boot code data and control code data from the host system, and to store at least one of the boot code data and control code data in the predetermined associated non-volatile memory cells of said flash memory device, which are addressed via the pointer stored in the first block;

a reset mode in which said flash memory controller reads said at least one of the boot code data and the control code data from said associated non-volatile memory cells of said flash memory device, and enables said input/output interface circuit to exchange data with the host system in accordance with protocols based on the boot code data and the control code data; and

a code updating mode in which at least one of updated boot code data and updated control code data are written into the flash memory device.

2. The electronic data flash card according to claim 1, wherein the flash memory device includes a first flash memory device and a second flash memory device, and wherein the flash memory controller includes means for supporting at least one of dual-channel parallel access and interleave access to the first flash memory device and the second flash memory device.

3. The electronic data flash card according to claim 1, wherein the input/output interface circuit, an internal power regulator, and a reset circuit are integrated or partially integrated in a single multi-chip package (MCP) or in a single integrated circuits (IC) chip.

4. The electronic data flash card according to claim 1, wherein the flash memory controller includes means for storing both the boot code data and the control code data in the flash memory device.

5. The electronic data flash card according to claim 1, wherein the flash memory controller includes means for storing first and second copies of the boot code data in the flash memory device.

6. The electronic data flash card according to claim 5, wherein the flash memory controller includes means for updating only the first copy of the boot code data in the flash memory device, and means for utilizing the second copy of the boot code data as a back-up copy.

7. The electronic data flash card according to claim 1, wherein the flash memory controller includes means for storing first and second copies of the control code data in the flash memory device.

8. The electronic data flash card according to claim 7, wherein the flash memory controller includes means for updating only the first copy of the control code data in the flash memory device, and means for utilizing the second copy of the control code data as a back-up copy.

9. The electronic data flash card according to claim 1, wherein the flash memory controller further comprises a volatile main memory circuit.

10. The electronic data flash card according to claim 9, wherein the flash memory controller further comprises means for transferring said at least one of the boot code data and the control code data from the flash memory device to the volatile main memory in accordance with instructions read from a read-only-memory (ROM).

11. The electronic data flash card according to claim 10, wherein said means for transferring said at least one of the boot code data and the control code data from the flash memory device to the volatile main memory comprises utilizing direct memory access (DMA) to transfer said at least one of the boot code and the control code from the flash memory device to the main memory.

12. The electronic data flash card according to claim 10, wherein the flash memory controller further comprises means for transferring the boot code data to the main memory before transferring the control code data to the main memory, and means for freeing up the main memory space occupied by the boot code data after the control code data is transferred to the main memory.

13. The electronic data flash card according to claim 1, wherein the flash memory controller comprises one of a 8051, 8052, 80286, RISC, ARM, MIPS and a digital signal processor.

14. The electronic data flash card according to claim 1, wherein the input/output interface circuit comprises one of a Universal Serial Bus (USB), Secure Digital (SD), Multi-Media Card (MMC), Compact Flash (CF), Memory Stick (MS), PCI-Express (PCIE), Integrated Drive Electronics (IDE), and a Serial Advanced Technology Attachment (SATA) interface circuit.

15. The electronic data flash card according to claim 1, wherein the first block is located at the beginning of the flash memory device and wherein the second block is located at any address of the flash memory device.

16. The electronic data flash card according to claim 15, wherein the second block is located at the bottom of address ranges of the flash memory device if the first block does not function properly.

17. An electronic data flash card adapted to be accessed by a host system that is capable of establishing a communication link, said electronic data flash card comprising:

(A) a card body;

(B) a flash memory device mounted on the card body, the flash memory device including a plurality of non-volatile memory cells;

(C) an input/output interface circuit mounted on the card body for establishing communication with the host system; and

(D) a flash memory controller mounted on the card body and electrically connected to said flash memory device and said input/output interface circuit, wherein the flash memory controller is configured to determine a type of the flash memory device by

sending a read command to the flash memory device, wherein if the flash memory device pulls down a read/busy# signal line after the read command is received, the flash memory device is associated with a small block type flash memory device, and

sending a confirm command to the flash memory device, wherein if the flash memory device pulls down the read/busy# signal line until the confirm command is received, the flash memory device is associated with a large block type flash memory device.