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1Gbit (32Mx32bit) Mobile SDR Memory
H55S1G(2/3)2MFP Series
Power Down
The Power Down command is used to reduce standby current. Before this command is issued, all banks must be pre-
charged and tRP must be passed after a precharge command. Once the Power Down command is initiated by keeping
CKE low, all of the input buffer except CKE are gated off.
Auto Refresh
The Auto Refresh command is used during normal operation and is similar to CBR refresh in Conventional DRAMs.
This command must be issued each time a refresh is required. When an Auto Refresh command is issued , the address
bits is ''Don't care'', because the specific address bits is generated by internal refresh address counter.
Self Refresh
The Self Refresh command is used to retain cell data in the Mobile SDRAM. In the Self Refresh mode, the Mobile SDRAM
operates refresh cycle asynchronously.
The Self Refresh command is initiated like an Auto Refresh command except CKE is disabled(Low). The Mobile SDRAM
can accomplish an special Self Refresh operation by the specific modes(PASR) programmed in extended mode registers.
The Mobile SDRAM can control the refresh rate automatically by the temperature value of Auto TCSR(Temperature
Compensated Self Refresh) to reduce self refresh current and select the memory array to be refreshed by the value of
PASR(Partial Array Self Refresh). The Mobile SDRAM can reduce the self refresh current(IDD6) by using these two
modes.
Deep Power Down
The Deep Power Down Mode is used to achieve maximum power reduction by cutting the power of the whole memory
array of the devices.
For more information, see the special operation for Low Power consumption of this data sheet.
Rev 1.2 / Jun. 2008
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HYNIX [ HYNIX SEMICONDUCTOR ]
