HY5Y7A2DLM-HF Datasheet, PDF (9/26 Pages) Hynix Semiconductor – 4Banks x 4M x 32bits Synchronous DRAM

Preliminary
HY5Y7A2DLM-HF
4Banks x 4M x 32bits Synchronous DRAM
Precharge
The Precharge command is used to close the open row in a particular bank or the open row in all banks. When the
precharge command is issued with address A10, high, then all banks will be precharged, and If A10 is low, the open
row in a particular bank will be precharged. The bank(s) will be available when the minimum tRP time is met after the
precharge command is issued.
Auto Precharge
The Auto Precharge command is issued to close the open row in a particular bank after READ or WRITE operation. If
A10 is high when a READ or WRITE command is issued, the READ or WRITE with Auto Precharge is initiated.
Burst Termination
The Burst Termination is used to terminate the burst operation. This function can be accomplished by asserting a Burst
Stop command or a Precharge command during a burst READ or WRITE operation. The Precharge command interrupts
a burst cycle and close the active bank, and the Burst Stop command terminates the existing burst operation leave the
bank open.
Data Mask
The Data Mask comamnd is used to mask READ or WRITE data. During a READ operation, When this command is
issued, data ouputs are disabled and become high impedance after two clock delay. During a WRITE operation, When
this command is issued, data inputs can’t be written with no clock delay.
Clock Suspend
The Clock Suspend command is used to suspend the internal clock of DRAM. During normal access mode, CKE is keeping
High. When CKE is low, it freezes the internal clock and extends data Read and Write operations.
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 Coventional 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 SDR. In the Self Refresh mode, the Mobile SDR
operates refresh cycle asynchronously. The Self Refresh command is initiated like an Auto Refresh command except
CKE is disabled(Low). The Mobile SDR can accomplish an special Self Refresh operation by the specific modes(TCSR,
PASR) programmed in extended mode registers. The Mobile SDR can control the refresh rate by the temperature value
of TCSR (Temperature Compensated Self Refresh) and select the memory array to be refreshed by the value of
PASR(Partial Array Self Refresh). The Mobile SDR 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. 0.1 / Feb. 2004
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