Seagate ST9100011FS ユーザーズマニュアル

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Pulsar Product Manual, Rev. A
15
2.11
Reliability
2.11.1
Annualized Failure Rate (AFR) and Mean Time Between Failures (MTBF)
The product shall achieve an Annualized Failure Rate - AFR - of 0.44%. AFR and MTBF are population statis-
tics that are not relevant to individual units.
AFR and MTBF specifications are based on the following assumptions:
• 8760 power-on-hours per year.
• 250 average power cycles per year.
• Operations at nominal voltages.
• Systems will provide adequate cooling to ensure the case temperatures do not exceed specification.
2.11.2
Reliability specifications
Unrecoverable read error rate during typical 
product lifetime 
1 LBA per 10
16
 bits read, max
Unrecoverable read error rate as product 
approaches end of useful life
1 LBA per 10
15
 bits read, max  [1]
Annualized Failure Rate (AFR)
0.44%
Power cycles
50,000 cycles
 
(at nominal voltage and temperature, with 60 cycles per hour and a 50% 
duty cycle)
Warranty
support.seagate.com/customer/warranty_validation.jsp
You will be asked to provide the drive serial number, model number (or 
part number) and country of purchase. After submitting this information, 
the system will display the warranty information for your drive.
Preventive maintenance
None required.
Typical Data Retention with Power removed 
(at 25C)
1 year    [2]
Endurance
[1]
As NAND Flash devices age with use, the capability of the media to retain a programmed value begins to deteriorate. 
This deterioration is affected by the number of times a particular memory cell is programmed and subsequently 
erased. As deterioration continues, the memory will reach a point at which the amount of deterioration will exceed the 
error recovery capabilities of the drive. Therefore an unrecoverable error rate is provided to indicate the expected 
error rate as the device nears the end of its useful life due to the deterioration. 
[2]
As NAND Flash devices age with use, the capability of the media to retain a programmed value begins to deteriorate. 
This deterioration is affected by the number of times a particular memory cell is programmed and subsequently 
erased. When a device is new, it has a powered off data retention capability of up to ten years. With use the retention 
capability of the device is reduced. Temperature also has an effect on how long a Flash component can retain its pro-
grammed value with power removed. At high temperature the retention capabilities of the device are reduced. Data 
retention is not an issue with power applied to the SSD. The SSD drive contains firmware and hardware features that 
can monitor and refresh memory cells when power is applied.
[3]
Endurance is the expected life of a product when subjected to a specified workload at a specified operating and stor-
age temperature. For the specific workload and performance to achieve this level of endurance, please reference sec-
tion 2.4.3.