K4J55323QF-GC Datasheet, PDF (17/49 Pages) Samsung semiconductor – 256Mbit GDDR3 SDRAM

K4J55323QF-GC
256M GDDR3 SDRAM
LOW POWER MODE
Low power mode can be enabled by A11="H" during the EMRS command and in this case, Precharge Power
Down command activates LP mode1 and Self Refresh command activates LP mode2. In case that A11 set to
"L" during the EMRS, Low Power mode is disabled and Precharge Power Down command and Self Refresh
command will do normal operation.
If a Precharge Power Down command issued under the condition of Low Power mode enabled, a device
enters the LP mode1 and it can reduce Precharge Power Down current significantly by disabling DLL during
the Precharge Power Down, however it requires more time to exit Power Down. If the power down duration is
less than 20us, the required tPDEX is 300tCK. Otherwise, 20000tCK required for the tPDEX.
If a Self Refresh command issued under the condition of Low Power mode enabled, a device enters the LP
mode2 and it can reduce tXSR while slightly increase the Self Refresh current. If the Self Refresh duration is
less than 20us, the required tXSR is 300tCK. Otherwise, 20000tCK required for the tXSR.
Low Power
Command
Disabled
(A11="L" @ EMRS)
Enabled
(A11="H" @ EMRS)
Comments
. DLL disabled for the purpose of current
Precharge Power Down Precharge Power Down
LP Mode1
saving ( ICC2P minimized)
. tPDEX increased
- 300tCK@ power down exit within 20us
0
- 20KtCK@ power down exit after 20us
. Short tXSR
Self Refresh
Self Refresh
LP Mode2
- 300tCK@ Self Refresh exit within 20us
- 20KtCK@ Self Refresh exit after 20us
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Rev 1.8 (Apr. 2005)