JP2009087479A - Inspection method for reading data of hard disk drive - Google Patents

Abstract

The quality of a hard disk drive (HDD) product is determined accurately in a short time.
An inspection area setting step for designating a sampling area of data recorded in an HDD, a data size setting step for setting a size of data acquired from the HDD, and a start of determining a start sector of data acquired from the HDD Start the sector determination step, the data acquisition step for reading the first data and the second data for the size set in the data size setting step from the start sector determined in the start sector determination step, and the first data read in the data acquisition step A data recording process for writing from the sector and a data comparison process for reading the second data from the start sector again and comparing it with the first data, and the data size set in the data size setting process and the start determined in the start sector determination process Using the sector, record in the sampling area set in the inspection area setting process The data are compared with withdrawn repeated .The 10

Description

  The present invention relates to an inspection method for determining product quality of a hard disk drive mounted on a digital electronic device by reading data.

  In recent years, as hard disk drives have become smaller and lighter, have larger storage capacities, and access speeds have increased, they have been built into portable music players, digital video cameras, digital still cameras, etc. as well as laptop computers. Digital electronic devices based on the premise have been actively taken out outdoors.

  However, in the manufacturing process of digital electronic devices with a built-in hard disk, shocks and vibrations applied during the transportation of the hard disk, mounting in the housing of the digital electronic device, and quality inspection of the digital electronic device mounted with the hard disk In some cases, it is necessary to inspect the quality of hard disk drive products during the manufacturing process of digital electronic equipment.

  FIG. 4 is a conceptual configuration diagram of the hard disk drive.

  In FIG. 4, a hard disk drive 400 includes a platter 401, which is a metal disk coated with a magnetic material for recording data on both sides, a motor 402 for rotating the platter 401 at a high speed, and a tip of an arm 405. There is an actuator 404 for moving the magnetic head 403 located on the platter 401 to an arbitrary position. Depending on the control method of the hard disk drive, the actuator 404 may retract the magnetic head 403 to a position 416 on the outer periphery of the platter 401 when the hard disk drive 400 is not operating.

  The digital electronic device on which the hard disk drive 400 is mounted has a CPU 406 and a memory 411, and an OS 412 is resident in the memory 411. When the OS 412 requests data access to the hard disk drive 400, a command 408 is issued from the CPU 406, and the HDD controller 407 moves the actuator 404 to a predetermined position and reads data via the magnetic head 403. Then, after temporarily storing the data 410 in the memory 409 for improving the processing speed, the data 413 is transferred to the memory 411 of the digital electronic device.

  FIG. 4A is a view of the cylinder as viewed from the side. In the hard disk drive 400, a plurality of platters 401 are arranged coaxially, and a cylinder 414 is formed. By increasing the number of cylinders, the storage capacity of the hard disk drive can be increased.

  FIG. 4B is a view of the platter viewed from the side. A magnetic head 419 and a magnetic head 420 are disposed on both sides of the platter 421 and joined to the actuator 415 in order to access recorded data.

  FIG. 4C shows the platter viewed from above. On the surface of the platter, there are a plurality of concentrically divided tracks 417, and the track 417 has radially divided sectors 418, which are recording units in the hard disk drive.

  FIG. 5 is a diagram illustrating a mechanism in which a malfunction occurs in the hard disk drive due to an impact.

  FIG. 5A is an enlarged view of the vicinity of the magnetic head 419 in FIG.

  In FIG. 5A, the platter 421 shown in FIG. 4B is coated with a magnetic material 501 for recording data on a metal disk substrate 500. A slider 502 is attached to the magnetic head 419 in FIG. 4B, and the slider 502 is joined to the arm 503 and supported by the actuator 415 in FIG.

  The disk substrate 500 rotates at a tremendous speed of several hundred revolutions per second, and the magnetic head 419 shown in FIG. 4B uses a slider 502 and uses the flow of air when the disk substrate 500 rotates at high speed. It floats on the magnetic body 501. The flying height 504 is as extremely small as about 0.1 μm.

  In addition, when the disk substrate 500 is less than the number of rotations enough to lift the slider 502, the slider 502 cannot generate buoyancy. For this reason, the magnetic head 419 shown in FIG. 4B contacts the magnetic body 501 or moves to a CSS zone (Contact Start Stop Zone) which is a retraction area of the magnetic head provided on the disk substrate 500. They were in contact (this method is called the CSS method).

  Further, in the case of a hard disk drive mounted on a digital electronic device that is assumed to be portable, when the hard disk drive is not operating, or when an impact sensor mounted on the hard disk drive detects an impact, the outer periphery of the platter 401 as shown in FIG. Many of them have a mechanism for waiting the magnetic head at a position 416 (this method is called a load / unload method).

  FIG. 5B is a diagram illustrating a state in which the slider and the magnetic body are in contact with each other due to impact or vibration. There is a limit to the allowable shock resistance value of the hard disk drive, and when an impact or vibration exceeding the allowable shock resistance value is applied to the operating hard disk (the disk substrate 500 is rotating), the state 505 or the state 506 is obtained. The magnetic body 501 and the slider 502 come into contact with each other, and as a result, the vicinity of the track 507 disposed on the magnetic body 501 is fatally damaged to the extent that it becomes inaccessible (since the disk substrate 500 rotates, the slider 504 and the magnetic body 501 make a circular contact mark). Even when an impact or vibration exceeding the allowable impact resistance is applied to the hard disk that is not operating (the disk substrate 500 is stopped), the magnetic body 501 and the slider 502 come into contact with each other as in the state 505 and the state 506. As a result, the vicinity of the sector 508 existing in the track arranged on the magnetic body 501 is fatally damaged to the extent that it becomes inaccessible (the disk substrate 500 is stopped, so that the contact between the slider 504 and the magnetic body 501 occurs. In some cases, a point-like contact mark is formed.

  Therefore, conventionally, as a method for inspecting the quality of a hard disk drive product, data reading, data writing, and data comparison are performed for all sectors in the storage area of the hard disk drive. However, since the inspection by this method takes a long time, there is a disadvantage that the production efficiency is remarkably lowered when it is carried out in each manufacturing process. Further, when it is carried out in the final manufacturing process, it is unclear in which process the defect has occurred even if a defective product is detected. In addition, there is a problem that a lot of duplication work occurs in order to replace the hard disk from the finished product.

  Furthermore, there has been a problem that the time required for inspection increases as the storage capacity of the hard disk increases year by year.

  On the other hand, various devices have been made for improving the efficiency of production management of products related to hard disks.

  For example, Patent Document 1 proposes a system that records process progress information and pre-use history information on a hard disk for efficient quality control in the manufacturing process.

  Patent Document 2 proposes a process management method that achieves low costs by writing a serial number of a disk drive to a disk in order to efficiently manage a hard disk production process.

  Patent Document 3 proposes a production management system for efficiently performing work instructions having different contents for each product and product individual information registration work.

Patent Document 4 proposes a test method for a hard disk drive that makes it possible to attach and detach the hard disk drive at random.
JP-A-5-54549 Japanese Patent Laid-Open No. 11-312371 JP 2001-236114 A JP 2004-342116 A

  However, the conventional techniques including Patent Documents 1 to 4 cannot solve the problem to be solved by the present invention.

  A first object of the present invention is to provide an inspection method for accurately determining the quality of a hard disk drive product in a short time.

  It is a second object of the present invention to provide an inspection method for determining whether a hard disk drive product is good or not in the same required time even when the storage capacity of the hard disk drive increases.

  In order to solve the above-described problems, the hard disk drive product quality check method according to the present invention is a test method for determining the quality of a hard disk drive product mounted on a digital electronic device by reading data, and the data recorded on the hard disk drive An inspection area setting step for designating a sampling area, a start sector determination step for determining a start sector of data acquired from the hard disk drive, and data for setting a size of data acquired from the start sector determined in the start sector determination step Start the size setting step, the data acquisition step for reading the first data and the second data for the size set in the data size setting step from the start sector determined in the start sector determination step, and the first data read in the data acquisition step Write from sector A data recording step and a data comparison step of reading the second data from the start sector again and comparing it with the first data, using the data size set in the data size setting step and the start sector determined in the start sector determination step Thus, the time required for the comparison inspection can be shortened by repeatedly extracting and comparing the data recorded in the sampling area set in the inspection area setting step.

  In addition, the data size set in the data size setting process is suitable for inspection by setting the recording size of the tracks arranged concentrically on the surface of the platter constituting the hard disk drive to a value less than the minimum value. The upper limit of the data read size can be defined. Note that the data reading size suitable for inspection refers to data comparison for at least one sector for each track included in the sampling area set in the inspection area setting process as a result of repeated sampling comparison. This is the read size that can guarantee that the process performs the comparison between the first data and the second data.

  Further, the interval between the Nth start sector and the (N-1) th start sector determined in the start sector determination step is the smallest in the recording size of the tracks arranged concentrically on the surface of the platter constituting the hard disk drive. By setting a numerical value equal to or smaller than the value, an upper limit of the thinning size of data suitable for inspection can be defined. Note that the data thinning size suitable for inspection refers to data comparison for at least one sector for each track included in the sampling area set in the inspection area setting process as a result of repeated sampling comparison. This is a data thinning size that can guarantee that the process performs a comparison between the first data and the second data.

  Furthermore, the interval between the Nth start sector and the (N-1) th start sector determined in the start sector determination step is not less than the numerical value set in the data size setting step, so that the data thinning size suitable for the inspection can be reduced. A lower limit can be defined. Here, the data thinning size suitable for the inspection means that the data comparison process does not perform comparison between the first data and the second data for the same sector as a result of repeated sampling comparison. It is the thinning size of data that can be done.

  It is desirable that the data reading size is ½ or less of the upper limit value of the reading size described above, and the data thinning size is the upper limit value of the thinning size described above. The inspection time increases because the number of data accesses increases as the read size increases, and a contact mark (contact mark of the track 507 in FIG. 5C) in which all sectors on the track are broken is detected. It is sufficient to inspect one sector per track.

  Further, in order to inspect all the sectors existing in the hard disk drive, the maximum “interval between the Nth start sector determined in the start sector determination step and the N−1th start sector” is set to “data size setting”. It is necessary to carry out sampling inspections for the number of times obtained by adding 1 to the value divided by “the numerical value set in the process” (when there is a remainder after the decimal point in the above division).

  Furthermore, depending on the storage capacity of the hard disk drive, it is possible to change the reading size so that the time required for inspection is the same. For example, if the data read size is halved for a hard disk drive with a storage capacity of 100 GB and ¼ for a hard disk drive with a storage capacity of 50 GB and further ¼ for a hard disk drive with a 200 GB storage capacity, the time required for inspection will be substantially the same. . Even in this case, as a result of repeated sampling comparison, the data comparison process compares the first data and the second data for at least one sector for each track included in the sampling area set in the inspection area setting process. Needless to say, you have to guarantee that.

  Further, if the data thinning size is set to the upper limit value of the thinning size (the data reading size is equal to or smaller than the upper limit value), as a result of repeated sampling comparison, at least for each track included in the sampling region set in the inspection region setting step, For one sector, it can be ensured that the data comparison process performs a comparison between the first data and the second data.

  In addition, there is a process number conversion step for converting the process number assigned to the production process into a numerical value within a predetermined range by a predetermined calculation so that the first start sector determined in the start sector determination process is different for each process number. As a result, it is possible to detect a product defect depending on a specific track of the hard disk drive generated in each production process while reducing the inspection time in the same production process. Further, when the product is completed, the inspection of all the storage areas of the hard disk drive can be completed, and it is possible to detect a product defect depending on a specific sector of the hard disk drive.

  In addition, there is a serial number conversion step for converting a serial number assigned to the digital electronic device into a numerical value within a predetermined range by a predetermined calculation, so that the first start sector determined in the start sector determination step is different for each serial number. By doing so, it is possible to detect in units of defective product lots depending on a specific sector of the hard disk drive while reducing the inspection time in the same production process.

  According to the hard disk drive data reading inspection method of the present invention, it is possible to provide an inspection method for accurately determining the quality of a hard disk drive product in a short time. Furthermore, even when the storage capacities of the hard disk drives are different, it is possible to provide an inspection method for determining whether or not the hard disk drive is good in the same required time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a conceptual configuration diagram of a digital electronic device according to a first embodiment of the present invention.

  In FIG. 1, a mother board 100 is used for fixing main components constituting a digital electronic device and attaching a connector. The CPU 101 is a central processing unit, and the north bridge 102 controls data transmission among the memory 110, the CPU 101, and the graphic chip 104. The monitor 115 outputs a video signal transmitted from the north bridge via the graphic chip 104. The south bridge 103 controls data transmission between the interfaces with the connected devices. As main interfaces, ATA 106 (IDE) which is an interface of ODD 116 (optical disk drive) and HDD 117 (hard disk drive), I / O controller 122 which is an interface of keyboard pointing device 118, and Ethernet (registration) of LAN 119 are registered. (Trademark) controller 108, a modem controller 109 that is an interface of a modem 120, and a USBxN 105 that is an interface of a USB device. The flash memory 107, which is a non-volatile memory, incorporates a BIOS (Basic Input / Output System) that is a program for controlling the various devices that make up the digital electronic device, and device operation settings are stored in the south bridge 103. It is held in a certain CMOS 113. The battery 111 is a backup power source for the CMOS 113. The jumper SW 121 (jumper switch) is connected to each pin of the GPIO 112 in the south bridge 103, and the setting state can be acquired via the BIOS. The RTC 114 (real time clock) operates by supplying power from the battery 111 even when the power source of the digital electronic device is cut off, and continues to count the correct date and time. The μCPU 123 (microcomputer) controls the operation of the motor 124 for operating the internal and external power control (not shown) and the biplate function.

  FIG. 2 is an external view of the digital electronic apparatus according to the first embodiment of the present invention.

  In FIG. 2, a housing 20 of a notebook computer, that is, a digital electronic device, includes a hard disk (not shown), a liquid crystal monitor 21, a keyboard 22, a touch pad 23, a LAN connector 24, a modem connector 25, and a USB connector 26. Various devices such as the optical disk drive 27 are mounted.

  FIG. 3 is an exploded development view of the hard disk drive shock absorbing unit according to the first embodiment of the present invention.

  In FIG. 3, the hard disk drive shock absorbing unit is composed of a hard disk drive 30, a signal cable 31, a concave shock absorbing holder 32 and a flat shock absorbing holder 33, except for a part of the signal cable. Protects hard disk drives from shocks in six directions. The signal cable is inserted into the connector of the ATA 106 (see FIG. 1). When such a hard disk drive shock absorbing unit is mounted, the shock resistance performance of the hard disk drive is significantly improved.

  However, because it does not guarantee improvement in impact resistance in the manufacturing process of products with built-in hard disk drives (especially when mounting hard disk drives in drive shock absorption units or digital electronic devices), The handling of hard disk drives is one of the most sensitive matters in each manufacturing process.

  FIG. 12 is a conceptual explanatory diagram of the LAB method for accessing the sectors of the hard disk drive according to the first embodiment of the present invention.

  As a method for accessing a sector of a hard disk drive, an LBA (Logical Block Addressing) method is generally used. This is a method of accessing data recorded in a physical sector of a hard disk drive by designating logical numbers assigned to all sectors of the hard disk drive.

  In FIG. 12, for simplicity of explanation, it is assumed that the hard disk drive has two magnetic disk surfaces, eight tracks arranged on the magnetic disk surface, and ten sectors arranged on each track. In addition, in order to improve the access processing speed of the hard disk drive, the sector number assignment in the LBA method is such that sectors arranged in tracks on the outer peripheral side of each magnetic disk surface are preferentially stored in the LBA table in units of tracks. Assume that it is allocated at the beginning.

  FIG. 12A shows a logical sector of the hard disk drive associated with the LBA table. FIG. 12B shows physical tracks and sectors of the hard disk drive.

  In FIG. 12, the LBA table has a sector item 1229 for storing the sector number of the hard disk drive and an ID item 1228 assigned to the sector number of the hard disk drive.

  The sector 1200 in the outermost track of the platter 1 is stored in the head of the LAB table, that is, ID (0) 1222, and the sectors in the outermost track of the platter 1 are stored thereafter, such as sector 1201. Yes. After the sector in the outermost track of the platter 1, the sector 1202 and subsequent sectors in the track on the innermost side in the platter 1 are stored.

  Further, the sector 1204 on the outermost track in the platter 2 is stored in the ID (30) 1223 after the sector 1203 and subsequent sectors in the other inner track in the platter 1. Thereafter, sectors in the outermost track of the platter 2 are stored as sectors 1205... After the sector in the outermost track of the platter 2, the sectors after the sector 1206 in the track on the innermost side in the platter 2 are stored.

  Next, after the sector 1207 and subsequent sectors in the other inner track in the platter 2, the sector 1208 in the third inner track from the outermost track in the platter 1 is stored in the ID (60) 1224. Yes. Similarly, after the sectors in the two inner tracks are stored, three sectors from the sector 1212 in the innermost track in the platter 2 are ID (90) 1225. Is stored from.

  Subsequently, from the ID (120) 1226, sectors of two tracks are stored from the sector 1216 in the six inner tracks from the outermost track in the platter 1, and finally from the ID (140) 1227, the platter 2 2 stores sectors corresponding to two tracks from the sector 1219 in the six inner tracks from the outermost track.

  As described above, all the sectors of the hard disk drive are associated with each other by the LBA table, and the data recorded in the sector of the hard disk drive can be accessed by specifying the ID of the LBA table.

  Further, the sector occupying 1/3 in the track near the outer periphery of each platter of the hard disk drive is associated with 1/3 from the head of the LBA table. A sector occupying 1/3 in the track near the inner circumference is associated with 1/3 from the end of the LBA table. Further, since the sector occupying 1/3 in the track near the center is associated with 1/3 near the center of the LBA table, a predetermined recording area is designated when performing a data reading inspection. It is also easy to access data recorded in the sector.

  FIG. 6 is a manufacturing process diagram of a product incorporating the hard disk drive according to the first embodiment of the present invention.

  In FIG. 6A, the hard disk drive delivered from the hard disk drive vendor is unpacked in delivery 600, and quality inspection is performed at the time of acceptance. Here, there is a possibility that a defect of the hard disk drive has occurred on a lot basis due to shock or vibration applied during transportation for delivery. In addition, defects may occur due to inappropriate handling after quality inspection.

  Next, in step A601, an inspection program for performing an OS and automatic inspection is mounted on the hard disk drive. Again, improper handling of the hard disk can cause defects on each hard disk drive.

  Next, in step B602, various devices such as a hard disk drive are mounted on the digital electronic device. Again, improper handling of the hard disk can cause defects on each hard disk drive.

  Next, in step C603, various inspections are performed while applying thermal stress for a predetermined time to the digital electronic device. At this stage, since the hard disk drive is mounted on the casing of a digital electronic device having various shock resistance absorbing mechanisms, the shock resistance performance is improved. However, due to some external factor, the hard disk drive (the digital electronic device with built-in) may be subjected to shock or vibration, and a defect may occur for each hard disk drive.

  Further, in step D604, various inspections are performed while applying vibration stress for a predetermined time to the digital electronic device. Again, the hard disk drive (digital electronic device with built-in) may be shocked or vibrated by some external factor, and there is a possibility that a defect has occurred in each hard disk drive.

  Next, in step E605, the digital electronic device for which all inspections have been completed is packed in a packaging box.

  Finally, in the shipment 606, a product guaranteed as a non-defective product is shipped.

  In the manufacturing process described above, it is possible to detect defects in the hard disk drives that have occurred in steps A601 to E605 if data is read from all storage areas of all hard disk drives in step E605. is there. However, when a defect is detected, the man-hours required for repair and re-inspection are more than the man-hours required for mounting (disassembly, re-mounting, re-inspection). Furthermore, since it is unclear in which manufacturing process the defect has occurred, it is difficult to take effective measures to prevent recurrence.

  On the other hand, if data reading is performed on all storage areas of the hard disk drive in all processes from delivery 600 to process E605, it is possible to detect defects occurring in each process at an early stage. The time for inspection increases and productivity decreases significantly.

  Furthermore, with the conventional method, it is not easy to detect all defects caused by an impact applied to a specific hard disk even when a sampling inspection is performed for each product in all processes from delivery 600 to process E605. Absent.

  The delivery 600, the process A601, the process B602, the process C603, the process D604, the process E605, and the shipment 606 are given for explanation of this embodiment, and the number of processes and the work contents to be performed in each process are as follows. It does not always coincide with the actual manufacturing process.

  The product is given a serial number as shown in FIG. The year 607 indicates the manufacturing year, the month 608 indicates the manufacturing month, and the day 609 indicates the manufacturing date. A line number 610 is a manufacturing location (such as a manufacturing line), and a serial number 611 is a serial number of a product manufactured on the same date.

  FIG. 7 is a diagram for explaining inspectable sectors when the sampling inspection of different areas is performed four times for each process according to the first embodiment of the present invention.

  In FIG. 7, to simplify the explanation, it is assumed that the hard disk drive to be inspected has one magnetic disk surface, eight tracks arranged on the magnetic disk surface, and 24 sectors arranged on each track. Note that an actual hard disk drive has 10 or more magnetic disk surfaces, 100 or more tracks per magnetic disk surface, and 100 or more sectors per track, and tracks on the outer circumferential side than tracks on the inner circumferential side. The number of sectors to be placed in is increasing. Therefore, the track with the smallest track recording size is the innermost track.

  In addition, if the sector in the hard disk drive is accessed by the LBA method and all sectors are accessed using the LBA table shown in FIG. 12, the quality of the product can be judged.

  The data extraction area set in the inspection area setting process is “all areas of the hard disk drive”, and the data size set in the data size setting process is “1/4 of the sector existing in the innermost track, that is, “6 sectors”, the interval between the Nth start sector and the N−1th start sector determined in the start sector determination step is “the number of sectors existing in the innermost track, that is, 24 sectors”, and the leading number of the LBA A sampling inspection when it is assumed that is assigned to the first start sector 700 will be described.

  In the sampling inspection of FIG. 7, the interval between the Nth start sector determined in the start sector determination step and the N−1th start sector is 24 sectors, and the data size set in the data size setting step is 6 sectors. In some cases, it is necessary to perform four sampling inspections in order to inspect all sectors existing in the hard disk drive.

  Moreover, a process number conversion process acquires the process number provided to the manufacturing process shown to FIG. 6 (A), and converts this into the numerical value of a predetermined range. The optimum predetermined range for the sampling inspection is preferably the number of times (in this case, “4”) necessary for inspecting all the sectors existing in the hard disk drive. Therefore, in this case, the integer value is in the range of 0 to 3.

  Further, assuming that a process number “0” is assigned to the process B602 shown in FIG. 6A, “1” is assigned to the process C603, “2” is assigned to the process D604, and “3” is assigned to the process E605. In B602, the first sampling inspection shown in FIG. 7A, in the process C603, the second sampling inspection shown in FIG. 7B, in the process D604, the third sampling inspection shown in FIG. 7C, in the process E605. The fourth sampling inspection shown in FIG. 7D is executed. When sampling inspection is carried out also in other processes, if a remainder value obtained by dividing an arbitrary process number given to the manufacturing process by a predetermined range (“4”) is calculated, a range from 0 to 3 is calculated. It becomes a numerical value, and if a numerical value is appropriately added to the above-described remainder numerical value, a numerical value in an arbitrary range having a width of 4 is obtained, so this numerical value may be used.

  FIG. 7A shows a sector that can be inspected by the first sampling inspection and a sector that has been cumulatively inspected. The data for “data size, 6 sectors” is accessed from the first start sector 700 to judge whether the sector is good or bad. After that, the start sector determination step adds “the number of sectors existing in the innermost track, 24 sectors” to the first start sector 700 to add the second start sector 709, the third start sector 710, and the fourth time. When the start sector 711 is determined, the data is accessed, and the data is accessed until the last sector given by the LBA, and when no more start sectors can be determined, the first sampling inspection is completed, and the first sampling inspection is completed. The quality of the sector shown in the area 701 is determined.

  In the first sampling inspection, only a quarter of the sampling area set in the inspection area setting step is inspected, but at least one sector is judged pass / fail for each track existing in the sampling area. It is possible to detect a track 507 that has been fatally damaged as shown in FIG.

  Next, FIG. 7B shows a sector that can be inspected by the second sampling inspection and a sector that has been cumulatively inspected. In the same manner as the sampling inspection shown in FIG. 7A, data for “data size, 6 sectors” is accessed from the first start sector 702 to judge the quality of the sector. At this time, the first start sector 702 is obtained by adding the data size “6 sectors” to the first start sector 700 shown in FIG. Since the subsequent steps are the same as in FIG. 7A, the description is omitted. When the second sampling inspection is completed, it is determined whether the sectors existing in the area including the start sector 702 are good or bad. The quality of the sector indicated in the area 703 is determined by the sampling inspection.

  In the second sampling inspection, only a quarter of the sampling area set in the inspection area setting step is inspected, but at least one sector is judged as good or bad for each track existing in the sampling area. It is possible to detect a defect even when a new track 507 that has been fatally damaged as shown in FIG.

  Further, FIG. 7C shows a sector that can be inspected by the third sampling inspection and a sector that has been cumulatively inspected. In the same manner as the sampling inspection shown in FIG. 7A, data for “data size, 6 sectors” is accessed from the first start sector 704, and the quality of the sector is determined. At this time, the first start sector 704 is obtained by adding the data size “6 sectors” to the first start sector 702 shown in FIG. Since the subsequent steps are the same as in FIG. 7A, the description is omitted. When the third sampling inspection is completed, it is determined whether the sectors existing in the area including the start sector 704 are good or bad. The quality of the sector indicated in the area 705 is determined by the sampling inspection.

  In the third sampling inspection, only ¼ of the sampling area set in the inspection area setting process is inspected, but at least one sector is judged as good or bad for each track existing in the sampling area. It is possible to detect a defect even when a new track 507 that has been fatally damaged as shown in FIG.

  Finally, FIG. 7D shows a sector that can be inspected by the fourth sampling inspection and a sector that has been cumulatively inspected. Similarly to the sampling inspection shown in FIG. 7A, data for “data size, 6 sectors” is accessed from the first start sector 707 to judge whether the sector is good or bad. At this time, the first start sector 707 is obtained by adding the data size “6 sectors” to the first start sector 704 shown in FIG. The subsequent steps are the same as in FIG. 7A, and will be omitted. However, when the fourth sampling inspection is completed, it is determined whether the sectors existing in the area including the start sector 707 are good or bad. The quality of the sector indicated in the area 708 is determined by the sampling inspection.

  In the fourth sampling inspection, only a quarter of the sampling area set in the inspection area setting process is inspected, but at least one sector is judged as good or bad for each track existing in the sampling area. It is possible to detect a defect even when a new track 507 that has been fatally damaged as shown in FIG.

  Furthermore, by this time, it is also possible to detect the sector 508 that has been severely damaged as shown in FIG. 5 for each hard disk drive.

  As described above, in the process B602, the process C603, the process D604, and the process E605 in FIG. 6, each production process is performed while reducing the inspection time in the same production process to ¼ of the sampling area set in the inspection area setting process. It is possible to detect product defects occurring in

  FIG. 8 is a diagram for explaining inspectable sectors when the sampling inspection of different areas is performed three times for each process according to the first embodiment of the present invention.

  In FIG. 8, for simplicity of explanation, it is assumed that the hard disk drive to be inspected has one magnetic disk surface, eight tracks arranged on the magnetic disk surface, and 24 sectors arranged on each track.

  The data extraction area set in the inspection area setting process is “all areas of the hard disk drive”, and the data size set in the data size setting process is “1/4 of the sector existing in the innermost track, that is, “6 sectors”, the interval between the Nth start sector and the N−1th start sector determined in the start sector determination step is “3/4 of the number of sectors existing in the innermost track, that is, 18 sectors” Similar to FIG. 7, a sampling inspection when it is assumed that the LBA head number is assigned to the first start sector 800 will be described.

  In the sampling inspection of FIG. 8, the interval between the Nth start sector determined in the start sector determination step and the N−1th start sector is 18 sectors, and the data size set in the data size setting step is 6 sectors. In order to inspect all the sectors existing in the hard disk drive, it is necessary to carry out three sampling inspections.

  Moreover, a process number conversion process acquires the process number provided to the manufacturing process shown to FIG. 6 (A), and converts this into the numerical value of a predetermined range. The optimum predetermined range for the sampling inspection is preferably the number of times (in this case, “3”) necessary for inspecting all the sectors existing in the hard disk drive. Therefore, in this case, the integer value is in the range of 0 to 2.

  Further, assuming that a process number “0” is assigned to the process B602 shown in FIG. 6A, a process number “1” is assigned to the process C603, and a process number “2” is assigned to the process D604, the process B602 shown in FIG. In step C603, the second sampling inspection shown in FIG. 7B is executed, and in step D604, the third sampling inspection shown in FIG. 7C is executed. When sampling inspection is performed also in other processes, a numerical value in the range from 0 to 2 can be obtained by calculating a remainder value obtained by dividing an arbitrary process number assigned to the manufacturing process by a predetermined range (“3”). It becomes a numerical value, and if a numerical value is appropriately added to the above-described remainder numerical value, a numerical value in an arbitrary range having a width 3 is obtained, and this numerical value may be used.

  FIG. 8A shows a sector that can be inspected by the first sampling inspection and a sector that has been cumulatively inspected. The data for “data size, 6 sectors” is accessed from the first start sector 800 to judge the quality of the sector. Thereafter, the start sector determination step adds “3/4, 18 sectors of the number of sectors existing in the innermost track” to the first start sector 800 to add the second start sector 801 and the third start sector 802. The fourth start sector 803 is determined to access the data, and the data is accessed up to the last sector assigned by the LBA, and when no more start sectors can be determined, the first sampling inspection is completed, and the first That is, the quality of the sector indicated in the area 804 is determined by the sampling inspection.

  In the first sampling inspection, only 1/3 of the sampling area set in the inspection area setting step is inspected, but at least one sector is judged pass / fail for each track existing in the sampling area. It is possible to detect a track 507 that has been fatally damaged as shown in FIG.

  Next, FIG. 8B shows a sector that can be inspected by the second sampling inspection and a sector that has been cumulatively inspected. Similarly to the sampling inspection shown in FIG. 8A, data for “data size, 6 sectors” is accessed from the first start sector 805 to judge whether the sector is good or bad. At this time, the first start sector 805 is obtained by adding the data size “6 sectors” to the first start sector 800 shown in FIG. Since the subsequent steps are the same as in FIG. 8A, the description is omitted. When the second sampling inspection is completed, it is determined whether the sector existing in the area including the start sector 805 is good or not. The quality of the sector indicated in the area 806 is determined by the sampling inspection.

  In the second sampling inspection, only one third of the sampling area set in the inspection area setting process is inspected, but at least one sector is judged as good or bad for each track existing in the sampling area. It is possible to detect a defect even when a new track 507 that has been fatally damaged as shown in FIG.

  Finally, FIG. 8C shows a sector that can be inspected by the third sampling inspection and a sector that has been cumulatively inspected. Similarly to the sampling inspection shown in FIG. 8A, data for “data size, 6 sectors” is accessed from the first start sector 807, and the quality of the sector is determined. At this time, the first start sector 807 is obtained by adding the data size “6 sectors” to the first start sector 805 shown in FIG. The subsequent steps are the same as in FIG. 8A, and will be omitted. However, when the third sampling inspection is completed, it is determined whether the sectors existing in the area including the start sector 807 are good or bad. The quality of the sector indicated in the area 808 is determined by the sampling inspection.

  In the third sampling inspection, only one third of the sampling area set in the inspection area setting step is inspected, but at least one sector is judged as good or bad for each track existing in the sampling area. It is possible to detect a defect even when a new track 507 that has been fatally damaged as shown in FIG.

  Furthermore, by this time, it is also possible to detect the sector 508 that has been severely damaged as shown in FIG. 5 for each hard disk drive.

  As described above, in the process B602, the process C603, and the process D604 in FIG. 6, the inspection time in the same production process is reduced to 1/3 of the sampling area set in the inspection area setting process, and is generated in each production process. Product defects can be detected early. In addition, by appropriately changing the interval between the Nth start sector and the (N-1) th start sector determined in the start sector determination step and the data size set in the data size setting step, all the hard disk drives existing It is also possible to adjust the number of sampling inspections to inspect the sector.

  FIG. 9 is a diagram illustrating inspectable sectors when a sampling inspection of different areas is performed for each serial number of the product according to the first embodiment of the present invention.

  In FIG. 9, for the sake of simplicity, it is assumed that the hard disk drive to be inspected has one magnetic disk surface, eight tracks arranged on the magnetic disk surface, and 24 sectors arranged on each track.

  The data extraction area set in the inspection area setting process is “all areas of the hard disk drive”, and the data size set in the data size setting process is “1/4 of the sector existing in the innermost track, that is, As in FIG. 7, the interval between the Nth start sector and the (N-1) th start sector determined in the start sector determination step is “the number of sectors existing in the innermost track, that is, 24 sectors”. A sampling inspection when it is assumed that the LBA head number is assigned to the first start sector 900 will be described.

  In the sampling inspection of FIG. 9, the interval between the Nth start sector determined in the start sector determination step and the N−1th start sector is 24 sectors, and the data size set in the data size setting step is 6 sectors. In order to inspect all different areas of the hard disk drive, it is necessary to perform four sampling inspections.

  In the serial number conversion step, a serial number such as a manufacturing number shown in FIG. 6B is acquired from the product and converted into a numerical value within a predetermined range. The optimum predetermined range for the sampling inspection is preferably the number of times (in this case, “4”) necessary for inspecting all the different areas of the hard disk drive. Therefore, in this case, the integer value is in the range of 0 to 3. In addition, in the case of extracting a serial number of only a numerical value from the manufacturing number including characters shown in FIG. Then, if the numerical value of the remainder obtained by dividing the serial number 611 (“000005”) by the predetermined range (“4”) is calculated, the numerical value in the range from 0 to 3 (“1”) is obtained. If a numerical value is appropriately added to the numerical value, a numerical value in an arbitrary range having a width of 4 is obtained. Note that this sampling inspection is suitable for inspection performed in the delivery 600, the process E, etc. in the manufacturing process shown in FIG.

  The product having the production number converted to “0” by the serial number conversion process determines the quality of the sector existing in the area including the start sector 900 shown in FIG. Since this sector inspection method is the same as that in FIG.

  In this sampling inspection, only ¼ of the sampling area set in the inspection area setting step is inspected, but at least one sector is judged as good or bad for each track existing in the sampling area. It is possible to detect a track 507 that has been severely damaged as shown in FIG.

  Similarly, the product having the production number converted to “1” by the serial number conversion process is converted to “2” by the area including the start sector 901 shown in FIG. 9B and the serial number conversion process. The product having the production number is an area including the start sector 902 shown in FIG. 9C, and the product having the production number converted to “3” by the serial number conversion process is the start sector shown in FIG. 9D. The quality of the sector existing in the area including the area including 903 is determined. Since the inspection method for this sector is the same as that in FIG. 7A, it will be omitted. However, in these sampling inspections, only ¼ of the sampling area set in the inspection area setting process is inspected, but it exists in the sampling area. For each track, it is judged whether at least one sector is acceptable or not, and it is possible to detect the track 507 that has been fatally damaged as shown in FIG.

  Furthermore, when the sector 508 that has been fatally damaged as shown in FIG. 5 is generated in a specific lot unit, it can be detected by sampling inspection in a lot unit.

  FIG. 10 is a flowchart showing a process of performing a sampling inspection of different areas for each process according to the first embodiment of the present invention.

  In FIG. 10, first, in P101, the size of data read continuously from the start sector calculated in P108 is set.

  Next, in P102, the sector interval (width) between the Nth start sector and the N + 1th start sector calculated in P108 is set.

  In P103, the maximum number of inspection areas is calculated. The maximum number of inspection areas is an integer value obtained by dividing the “sector interval between the Nth start sector and the (N + 1) th start sector” set in P102 by “the size of data continuously read from the start sector” set in P101. is there.

  Further, in P104, it is confirmed whether or not a remainder of the integer value is generated in the calculation result of P103. If the remainder is generated, the maximum number of inspection areas is increased by 1 in P105.

  Next, in P106, an area (the number of which is to be calculated) for executing this sampling inspection is determined (details will be described later).

  When the area to be inspected is determined, in P107, a variable (N) for counting the number of calculation of the start sector used in P108 is initialized with zero. Then, after P108, it is inspected whether each sector is broken or not while repeatedly calculating “start sector for N-th data reading in the inspection area determined in P106”.

  In P108, “the start sector from which data is read for the Nth time in the inspection area determined in P106” is calculated. The position is obtained by multiplying “the size of the data to be read” obtained in P101 by “the number of the area in which the sampling inspection is performed” obtained in P106, and the “Nth start sector and N + 1 start sector set in P102”. It is calculated by adding the value obtained by multiplying the “sector interval (width) up to” by the “number of start sector calculations” initialized in P107.

  Next, in P109, the variable (i) for counting the “sector in which data continuously read from the Nth start sector” used in P110 is initialized with zero. After P110, it is checked whether each sector is broken.

  First, in P110, the data (DAT1) of the sector at the position of “variable (i)” is read with reference to the “start sector from which the Nth data reading is performed” calculated in P108. This can be done by reading the data of the sector associated with the ID of “variable (i)” from the “start sector from which data is read for the Nth time” in the LBA table shown in FIG. At this time, if there is no sector at the position of “variable (i)” with reference to “start sector from which data is read for the Nth time” in P111, “sampling inspection has been completed normally” in P112. And the sampling inspection in the inspection area determined in P106 is completed.

  On the other hand, if the designated sector exists, the data (DAT1) read in P110 is written in the same sector in P113.

  At P114, data (DAT2) is read again from the same sector. In P115, the data read in P110 (DAT1) and the data read in P114 (DAT2) are compared, and it is determined in P116 whether the two data match. If they do not coincide with each other, a message indicating that “sampling inspection has ended abnormally” is displayed in P117, and the sampling inspection in the inspection area determined in P106 is interrupted.

  On the other hand, if the two data match, P118 updates “variable (i)” by 1 to indicate the position of the next sector.

  Then, in P119, it is checked whether all data recorded in the sectors from “starting sector for reading data for the Nth time” to “data size specified in P101” have been compared, and comparison is still in progress. If there is no sector, return to P110. If all are compared, in P120, “Variable (N)” is updated by 1 in order to calculate the next start sector, and the process returns to P108.

  This sampling inspection is premised on being performed for “all areas of the hard disk drive”. If it is desired to target the “predetermined area of the hard disk drive”, as shown in FIG. 12, the predetermined area of the hard disk drive (for example, the area of the outer track 1/3, the inner track 1/3) Corresponding to the above, the reading range of the LBA table may be limited at P110 and P111.

  In the inspection process shown in FIG. 10, the inspection program of the present application is temporarily written in an empty area of the HDD 117 or the flash memory 107 before product shipment, and the CPU 101 reads the inspection program from the recording medium and executes it at the time of inspection. Then, the defective portion is detected.

  Alternatively, it is possible to detect a defective portion by executing an inspection program from an external control device (not shown) via a communication medium such as the LAN 119 and the Ethernet (registered trademark) controller 108.

  FIG. 11 is a flowchart showing a process for calculating the inspection area number according to the first embodiment of the present invention.

  The inspection area number includes a method of calculating from the “manufacturing process number” as described in FIGS. 7 and 8 and a method of calculating from the “serial number” as described in FIG.

  FIG. 11A is a flowchart of the process of calculating the inspection area number from the manufacturing process number. First, in P130, the “manufacturing process number” assigned to each manufacturing process is acquired.

  In P131, a remainder is obtained by dividing the “manufacturing process number” acquired in P130 by the “maximum number of inspection areas” calculated in P103 to P105 in FIG. 10, and this is used as the inspection area number.

  FIG. 11B is a flowchart of the process of calculating the inspection area number from the product serial number. First, the “product serial number” assigned to each product is acquired in P140.

  In P141, a remainder is obtained by dividing the “product serial number” acquired in P140 by the “maximum number of inspection areas” calculated in P105 to P105 in FIG. 10, and this is used as the inspection area number.

  10 and FIGS. 11 to 12, the inspection program of the present invention is temporarily written in an empty area of the HDD 117 or the flash memory 107 before product shipment, and the CPU 101 stores the inspection program at the time of inspection. Are read from the recording medium and executed to determine whether the product of the hard disk drive is good or bad.

  Alternatively, the product quality of the hard disk drive can be determined by executing an inspection program from an external control device (not shown) via a communication medium such as the LAN 119 and the Ethernet (registered trademark) controller 108.

  The hard disk drive data reading inspection method according to the present invention can provide an inspection method for accurately determining the product quality of a hard disk drive in a short time, and even if the storage capacity of the hard disk drive is different, the same required time can be provided. The quality of the hard disk drive product can also be determined.

The notional block diagram of the digital electronic device which concerns on the 1st Embodiment of this invention 1 is an external view of a digital electronic device according to a first embodiment of the present invention. 1 is an exploded development view of a hard disk drive shock absorption unit according to a first embodiment of the present invention. Conceptual configuration diagram of hard disk drive Diagram explaining how hard disk drives malfunction due to impact Manufacturing process diagram of a product incorporating a hard disk according to the first embodiment of the present invention The figure explaining the sector which can be test | inspected when the sampling inspection of a different area | region for every process which concerns on the 1st Embodiment of this invention was implemented 4 times. The figure explaining the sector which can be test | inspected when the sampling inspection of a different area | region for every process which concerns on the 1st Embodiment of this invention was implemented 3 times. The figure explaining the sector which can be test | inspected when carrying out the sampling inspection of a different area | region for every serial number of the product which concerns on the 1st Embodiment of this invention The flowchart which shows the process which implements the sampling inspection of a different area | region for every process which concerns on the 1st Embodiment of this invention. The flowchart which shows the process which calculates the test | inspection area number which concerns on the 1st Embodiment of this invention. 1 is a conceptual explanatory diagram of a LAB method for accessing a sector of a hard disk drive according to a first embodiment of the present invention.

Explanation of symbols

P101 Step for setting the size of data to be read continuously from the start sector P102 Step for setting the interval (width) between two adjacent start sectors P103 Step for calculating the maximum number of inspection regions P104 Whether to correct the maximum number of inspection regions Judgment step P105 Step of correcting the maximum number of inspection areas P106 Step of determining an area for performing sampling inspection P107 Step of initializing a variable for counting the number of start sector calculations P108 Step of calculating a start sector for reading data P109 Step for initializing a variable for counting a sector for reading data P110 Step for reading data for a specified sector P111 Step for determining whether there is a sector for reading data P112 Successful completion of inspection P113 Step of writing data in the designated sector P114 Step of reading data from the same sector again P116 Step of determining whether or not the two data match P117 Step of notifying abnormal interruption of inspection P118 Sector of reading data Step of updating a variable to be counted P119 Step of determining whether or not all specified data have been compared P120 Step of updating a variable to count the number of calculation of the start sector

Claims (8)

An inspection method for judging the quality of a hard disk drive mounted on a digital electronic device by reading data,
An inspection area setting step for designating a sampling area of data recorded in the hard disk drive;
A starting sector determination step for determining a starting sector of data acquired from the hard disk drive;
A data size setting step for setting a size of data acquired from the start sector determined in the start sector determination step;
A data acquisition step of reading the first data and the second data for the size set in the data size setting step from the start sector determined in the start sector determination step;
A data recording step of writing the first data read in the data acquisition step from the start sector;
Re-reading the second data from the starting sector and comparing it to the first data,
Using the data size set in the data size setting step and the start sector determined in the start sector determination step, the data recorded in the sampling area set in the inspection area setting step is repeatedly extracted and compared. An inspection method for product quality of hard disk drives. 2. The data size set in the data size setting step is a numerical value less than a minimum value of a recording size of a track divided and arranged concentrically on the surface of a platter constituting a hard disk drive. Inspection method of product quality of hard disk drive as described in. The interval between the Nth start sector and the (N-1) th start sector determined in the start sector determination step is the minimum value of the recording size of tracks arranged concentrically on the surface of the platter constituting the hard disk drive. The method of inspecting the quality of a hard disk drive product according to claim 1 or 2, wherein the following numerical values are used. The interval between the Nth start sector and the (N-1) th start sector determined in the start sector determination step is greater than or equal to a numerical value set in the data size setting step. Inspection method of hard disk drive products. A process number conversion step for converting the process number assigned to the production process into a numerical value within a predetermined range by a predetermined calculation,
5. The method for checking product quality of a hard disk drive according to claim 1, wherein a first start sector determined in the start sector determination step for each step number is different for each step number. A serial number conversion step of converting the serial number assigned to the digital electronic device into a numerical value within a predetermined range by a predetermined calculation,
5. The method for checking product quality of a hard disk drive according to claim 1, wherein a first start sector determined in the start sector determination step for each serial number is different for each serial number. The recording medium which recorded the program which controls the inspection method of Claims 1-6. A communication medium for distributing a program for controlling the inspection method according to claim 1.

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