MASS PRODUCTION TESTING OF USB FLASH CARDS WITH VARIOUS FLASH MEMORY CELLS

• US 20080177922A1
• Filed: 10/11/2007
• Published: 07/24/2008
• Est. Priority Date: 01/06/2000
• Status: Active Grant

• Current Assignee: Super Talent Technology, Corporation
• Original Assignee: Super Talent Electronics, Inc.
• Inventors: Shen, Ming-Shiang, Ma, Abraham C., Lee, Edward W., Chow, David Q.
• Granted Patent: US 7,788,553 B2
• Time in Patent Office: Days
• US Class Current: 710/302
• CPC Class Codes: G06F 11/2221 to test input/output devices or peripheral units

Abstract

A high volume testing/formatting process is provided for Universal Serial Bus-based (USB-based) electronic data flash cards (USB devices) that meets the increasing demand for USB electronic data flash cards (USB devices). A test host is simultaneously coupled to the multiple USB devices (e.g., using a multi-port card reader or a probe fixture), a controller endpoint value is read from each of the USB devices and verified with a known good value, and then testing/formatting is performed on each of the USB devices by writing predetermined data into each USB device in a pipelined manner, then reading out and testing the predetermined data. In one embodiment, the test host implements a special USB driver that blocks standard USB registration procedures upon detecting the plurality of USB devices. Control and/or boot code data are written onto the flash memory device (i.e., instead of being provided on a controller ROM).

Claims

1. A method for formatting/testing USB devices using a test host including a computing system, the method comprising:

coupling a plurality of USB devices to a test host, each USB device including a flash controller and one or more flash memory devices, wherein each USB device includes an extended USB connector plug attached to a printed circuit board (PCB) assembly (PCBA) or a chip-on-board (COB) having the one or more flash memory devices and the flash controller attached, wherein the extended USB connector plug includes

an extended pin substrate that has an extended length that is longer than or equal to a standard length of the pin substrate of the standard USB connector plug,

a plurality of plug standard metal contact pins disposed on the pin substrate, wherein when the standard pin substrate of the extended USB connector plug is inserted into a cavity of the standard USB socket, the standard metal contact pins make physical and electrical contact with plug standard metal contact pins on a plug pin substrate, and

a plurality of plug extended metal contact pins on the extended pin substrate, wherein when the extended pin substrate of the extended USB connector plug is inserted into a cavity of the extended USB socket, the plug extended metal contact pins on the extended pin substrate make physical and electrical contact with socket extended metal contact pins on the extended USB socket,

reading at least one controller endpoint descriptor value from each of the plurality of USB devices, and verifying that the controller endpoint descriptor values of each of the plurality of USB devices matches stored descriptor values stored in the test host; and

testing/formatting each of the USB devices having a valid endpoint descriptor value by writing predetermined data into the flash memory devices in a pipelined manner, and then reading the predetermined data from the flash memory device and comparing the read predetermined data with known good data stored in the test host.

2. The method according to claim 1, further comprising installing a USB driver into the test host that directs the computing system to block standard USB registration procedures upon detecting the plurality of USB devices.

3. The method according to claim 1, further comprising fabricating the plurality of USB devices such that the plurality of USB devices are connected to a panel.

4. The method according to claim 3, further comprising singulating the panel before said coupling said USB devices to said test host.

5. The method according to claim 4, wherein coupling all of said plurality of USB devices comprises plugging each of the plurality of USB devices into a corresponding port of a card reader, wherein the card reader is connected by a USB cable to the test host.

6. The method according to claim 3, further comprising singulating the panel after sequentially testing/formatting all of said plurality of USB devices.

7. The method according to claim 6, wherein coupling all of said plurality of USB devices to the test host comprises mounting a probe fixture onto the panel such that pins of each of the plurality of USB devices are contacted by corresponding probes of the probe fixture.

8. The method according to claim 1, wherein said reading said controller endpoint descriptor values from each of the plurality of USB devices comprises reading at least one of a configuration descriptor value, a mass storage class code value, a vendor identification value, and a product identification value.

9. The method according to claim 1, further comprising asserting a corresponding color flag displayed on a monitor of the test host upon verifying that the controller endpoint descriptor value stored in each of the plurality of USB devices matches said stored descriptor value.

10. The method according to claim 1, wherein said testing/formatting comprises scanning bad block data stored in the flash memory device, and verifying that reserved storage capacity of each flash memory device is equal to a predetermined amount.

11. The method according to claim 1, wherein said testing/formatting comprises writing at least two copies of bad block data identifying bad blocks on the flash memory device into predetermined blocks of the flash memory device.

12. The method according to claim 1, wherein the flash memory device comprises a plurality of non-volatile memory cells which can be an SLC (single level cell) type or an MLC (multi-level cell) type.

13. The method according to claim 12, wherein the SLC type memory cells include at least one of SSLC (Small Block SLC), LSLC (Large Block SLC) or a combination thereof, and wherein the MLC type memory cells include SMLC (Small Block MLC) and LSLC (Large Block MLC).

14. The method according to claim 13, wherein a small block includes 512+16 bytes per page and a large block includes 2048+64 bytes per page, wherein the 16 bytes of the small block and the 64 bytes of the large block are corresponding page spare areas.

15. The method according to claim 14, wherein the page is a unit for data read and data write, wherein a data write speed of the large block is four times faster than a corresponding one of the small block due to a page size difference.

16. The method according to claim 15, wherein a busy time of data write of the MLC memory cells is four times longer than SLC memory cells.

17. The method according to claim 12, wherein the SLC memory cells include 2 KByte per page type memory cells and 4 KByte per page type memory cells.

18. The method according to claim 1, wherein said testing/formatting comprises writing at least one of control code data and boot code data into predetermined blocks of the flash memory device.

19. The method according to claim 18, wherein writing to the flash memory devices comprises transmitting predetermined data from the test host to a first buffer of a first USB device, and causing the first USB device to write the predetermined data from the first buffer into the flash memory device of the first USB device while the test host transfers the predetermined data to a second buffer of a second USB device.

20. The method according to claim 1, wherein said sequentially testing/formatting comprises writing customer-provided data into predetermined blocks of the flash memory device.

21. The method according to claim 1, wherein said sequentially testing/formatting comprises writing updated serial number, date code, and produce version code values into predetermined write-protected portions of the flash memory device.