Automatic Sleep Mode; Dynamic Adjustment Of Performance Versus Power Consumption; Power Supply Requirements - SanDisk CompactFlash Product Manual

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Introduction to the CompactFlash Memory Card

1.6.5. Automatic Sleep Mode

A unique feature of the SanDisk CompactFlash Memory Card (and other SanDisk products) is automatic entrance

and exit from sleep mode. Upon completion of a command, the CompactFlash Card will enter sleep mode to

conserve power if no further commands are received within 5 msec. The host does not have to take any action for

this to occur. In most systems, the CompactFlash Memory Card is in sleep mode except when the host is accessing

it, thus conserving power. Note that the delay from command completion to entering sleep mode can be adjusted.

When the host is ready to access the CompactFlash Memory Card and it is in sleep mode, any command is sued to

the CompactFlash Card will cause it to exit sleep and respond. The host does not have to follow the ATA protocol of

issuing a reset first. It may do this if desired, but it is not needed. By not issuing the reset, performance is improved

through the reduction of overhead but this must be done only for the SanDisk products as other ATA products may

not support this feature.

This feature is no longer supported. This command will be treated as a NOP (No Operation) to guarantee backward

compatibility.

This is a dual voltage product, which means it will operate at a voltage range of 3.30 volts ± 5% or 5.00 volts ±

10%. Per the PCMCIA specification Section 2.1.1, the host system must apply 0 volts in order to change a voltage

range. This same procedure of providing 0 volts to the card is required if the host system applies an input voltage

outside the desired voltage by more than 20%. This means less than 4.0 volts for the 5.00 volt range and less than

2.70 volts for the 3.30 volt range.

CompactFlash

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