W968D6DA Datasheet, PDF (13/75 Pages) Winbond – Low-power features

W968D6DA
256Mb Async./Page,Syn./Burst CellularRAM
8.2.2 Page Mode READ Operation
Page mode is a performance-enhancing extension to the legacy asynchronous READ operation. In page-mode-
capable products, an initial asynchronous read access is performed, then adjacent addresses can be read quickly by
simply changing the low-order address. Addresses A[3:0] are used to determine the members of the 16-address
CellularRAM page. Any change in addresses A[4] or higher will initiate a new tAA access time. Page mode takes
advantage of the fact that adjacent addresses can be read in a shorter period of time than random addresses.
WRITE operations do not include comparable page mode functionality.
During asynchronous page mode operation, the CLK input must be held LOW. CE# must be driven HIGH upon
completion of a page mode access. WAIT will be driven while the device is enabled and its state should be ignored.
Page mode is enabled by setting RCR[7] to HIGH. ADV must be driven LOW during all page mode READ accesses.
Due to refresh considerations, CE# must not be LOW longer than tCEM.
8.2.2.1 Page Mode READ Operation (ADV# LOW)
CE #
<tCEM
OE #
WE #
ADDRESS
DATA
Add 0
tAA
Add 1
tAPA
Add 2
tAPA
Add 3
tAPA
D0
D1
D2
D3
LB # / UB #
Don’t Care
8.2.3 BURST Mode Operation
Burst mode operations enable high-speed synchronous READ and WRITE operations. Burst operations consist of a
multi-clock sequence that must be performed in an ordered fashion. After CE# goes LOW, the address to access is
latched on the rising edge of the next clock that ADV# is LOW. During this first clock rising edge, WE# indicates
whether the operation is going to be a READ (WE# = HIGH) or WRITE (WE# =LOW).
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Publication Release Date : June 27, 2013
Revision : A01-003