W3EG7266S-AD4 Datasheet, PDF (8/13 Pages) White Electronic Designs Corporation – 512MB - 64Mx72 DDR SDRAM UNBUFFERED ECC w/PLL

White Electronic Designs
W3EG7266S-AD4
-BD4
PRELIMINARY
DDR SDRAM COMPONENT ELECTRICAL CHARACTERISTICS AND RECOMMENDED
AC OPERATING CONDITIONS (Continued)
DDR400: VCC = VCCQ = +2.6V ± 0.1V
AC CHARACTERISTICS
403
355
262
265
202
PARAMETER
DQS write postamble
Write recovery time
SYMBOL MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX UNITS NOTES
tWPST 0.4 0.6 0.4 0.6 0.4 0.6 0.4 0.6 0.4 0.6 tCK 17
tWR
15
15
15
15
15
ns
Internal WRITE to READ command delay
tWTR
2
1
1
1
1
tCK
Data valid output window
REFRESH to REFRESH command interval
Average periodic refresh interval
Terminating voltage delay to VCC
Exit SELF REFRESH to non-READ command
Exit SELF REFRESH to READ command
na
tQH - tDQSQ tQH - tDQSQ tQH - tDQSQ
tQH - tDQSQ
tQH - tDQSQ
ns 22
tREFC
70.3
70.3
70.3
70.3
70.3 µs 21
tREFI
7.8
7.8
7.8
7.8
7.8 µs 21
tVTD
0
0
0
0
0
ns
tXSNR 75
75
75
75
80
ns
tXSRD 200
200
200
200
200
tCK
October 2004
Rev. 7
8
White Electronic Designs Corporation • [phone] • www.wedc.com