SanDisk SD-ROM, Руководство по эксплуатации продукта

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3 SanDisk SD-ROM Card Specifications
3.1 Operating Specifications
The table below summarizes the SD-ROM operating specifications.
Parameter Value Notes
Supply Voltage 2.0 – 3.6v during card identification for version 1.1 cards
2.7 – 3.6v all supported commands
Operating Temperature -25 – 85
°
C
Storage Temperature -40 – 85
°
C
Data Retention 100 years minimum
Data Endurance 1x10
9
read cycles
Interface speed 0 – 25MHz variable clock rate
Read Bandwidth 1.8MB/s minimum sequential read, 25MHz interface speed
Read Current
50mA typical
75mA maximum
maximum at 3.6v, 85
°
C
Sleep Current 250uA maximum
Reset to Read Latency 300ms
Read Command Response 100ms
3.2 Memory Capacity
SanDisk SD-ROM Cards are sold preloaded with an OEM-specified image which may or may
not have a file system. In general, a file system provides structure for data; the SD Card File
System Specification, published by the SDA, describes the file format system that is typically
implemented on SD cards.
SanDisk SD-ROM cards do not support the SD security features (CPRM), and are therefore
organized as a single non-secure partition. The content data can be accessed by the host
system using standard read commands.
The following table lists the available user space for 32, 64, and 128MB cards. Note that some
hosts cannot handle non-standard image sizes, so the allowable space for a particular
application may be less than shown in the table.
Capacity Maximum User LBA Maximum User Data Image Size
32 MB 63,488 31.0MB (32505856 bytes)
64 MB 129,024 63.0MB (66060288 bytes)
128 MB 260,096 127.0MB (133169152 bytes)
3.3 Register Values
The SD specifications define a set of eight registers within the card interface. However, the DSR
Register is optional and is not used in the SanDisk SD Card Product Family. For specific
information about all registers, refer to Section 5 of the SDA Physical Layer Specification,
Version 2.00.
SanDisk Confidential