W641GG2JB Datasheet, PDF (28/109 Pages) Winbond – 1-Gbit GDDR3 Graphics SDRAM

W641GG2JB
1-Gbit GDDR3 Graphics SDRAM
6.3.4 Minimum delay from RD/A and WR/A to any other command (to another bank) with concurrent AP
From Command
WR/A
RD/A
To Command
RD or RD/A
WR or WR/A
PRE
ACT
RD or RD/A
WR or WR/A
PRE
ACT
Minimum delay to another bank (with concurrent
auto precharge)
(WL + 2) × t_CK + t_WTR
2 × t_CK
t_CK
t_CK
2 × t_CK
(CL + 4 - WL) × t_CK
t_CK
t_CK
Note
6.4 Boundary Scan
6.4.1 General Description
The 1-Gbit GDDR3 incorporates a modified boundary scan test mode. This mode doesn‘t operate in accordance with IEEE
Standard 1149.1-1990. To save the current GDDR3 ball-out, this mode will scan the parallel data input and output the scanned data
through the WDQS0 pin controlled by SEN.
Note: Both pads CS1# and A12 will be activated and could be accessed during Boundary Scan.
6.4.2 Disabling the scan feature
It is possible to operate the GDDR3 without using the boundary scan feature. SEN (at U-4 of 136- ball package) should be tied
LOW(VSS) to prevent the device from entering the boundary scan mode. The other pins which are used for scan mode, RES, MF,
WDQS0 and CS will be operating at normal GDDR3 functionalities when SEN is deasserted.
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Publication Release Date: Apr, 22, 2011
Revision A01-002