MB81F643242C Datasheet, PDF (43/56 Pages) Fujitsu Component Limited. – 4 X 512 K X 32 BIT SYNCHRONOUS DYNAMIC RAM

MB81F643242C-60/-70/-10 Advanced Info (AE0.1E)
TIMING DIAGRAM – 15 : AUTO-REFRESH TIMING
CLK
Command
REF ^*1
NOP ^*3
BA0, BA1
*2
DON’T CARE
NOP ^*3
tRC (min)
NOP ^*3
REF
*2
DON’T CARE
NOP ^*3
tRC (min)
Command ^*4
BA
Notes: *1. All banks should be precharged prior to the first Auto-refresh command (REF).
*2. Bank select is ignored at REF command. The refresh address and bank select are selected by internal refresh counter.
*3. Either NOP or DESL command should be asserted during tRC period while Auto-refresh mode.
*4. Any activation command such as ACTV or MRS command other than REF command should be asserted after tRC from the
last REF command.
TIMING DIAGRAM – 16 : SELF-REFRESH ENTRY AND EXIT TIMING
CLK
CKE
tSI (min)
Command
NOP ^*1 SELF
tCKSP (min)
tRC (min) ^*4
DON’T CARE
NOP ^{*2 SELFX}
NOP ^*3 Command
Notes: *1. Precharge command (PRE or PALL) should be asserted if any bank is active prior to Self-refresh Entry command (SELF).
*2. The Self-refresh Exit command (SELFX) is latched after tCKSP (min). It is recommended to apply NOP command in
conjunction with CKE.
*3. Either NOP or DESL command can be used during tRC period.
*4. CKE should be held high within one tRC period after tCKSP.
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