eorex
EM42BM3284LBA
Recommended Power On and Initialization
The following power on and initialization sequence guarantees the device is preconditioned to each user’s
specific needs.
Provide power, the device core power (VDD) and the device I/O power (VDDQ) must be brought up
simultaneously to prevent device latch-up. Although not required, it is recommended that VDD and VDDQ
are from the same power source. Also assert and hold Clock Enable (CKE) to a LV-CMOS logic high level..
Once the system has established consistent device power and CKE is driven high, it is safe to apply stable
clock.
After power on, an initial pause of 200 µs is required followed by a precharge of all banks using the
precharge command.
Provide NOPs or DESL commands for at least tRP time.
Issue an auto-refresh command followed by NOPs or DESL command for at least tRFC time. Issue the
second auto-refresh command followed by NOPs or DESL command for at least tRFC time.
Note as part of the initialization sequence there must be two auto-refresh commands issued.
Using the MRS command, load the base mode register. Set the desired operating modes.
Provide NOPs or DESL commands for at least tMRD time.
Using the MRS command, program the extended mode register for the desired operating modes.
Provide NOP or DESL commands for at least tMRD time.
Now it is ready for any valid command.
Feb. 2009
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EOREX [ EOREX CORPORATION ]
