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Operating frequency: DC to 333 MHz
Supports DDRII SDRAM
Two operations modes: 25 bit (1:1) and 14 bit (1:2)
1.8V operation
Fully JEDEC-compliant
96-ball LFBGA
The device monitors both DCS# and CSR# inputs and will gate
the Qn outputs from changing states when both DCS# and
CSR# inputs are high. If either DCS# or CSR# input is low, the
Qn outputs will function normally. The RESET input has priority
over the DCS# and CSR# control and will force the outputs
low. If the DCS#-control functionality is not desired, the CSR#
input can be hardwired to ground, in which case the set-up
time requirement for DCS# would be the same as for the other
D data inputs.
The device supports low-power standby operation. When the
reset input (RESET#) is low, the differential input receivers are
disabled, and undriven (floating) data, clock, and reference
voltage (VREF) inputs are allowed. In addition, when RESET#
is low, all registers are reset and all outputs are forced low. The
LVCMOS RESET# and Cn inputs must always be held at a
valid logic high or low level. To ensure defined outputs from the
register before a stable clock has been supplied, RESET#
must be held in the low state during power-up.
In the DDR-II RDIMM application, RESET# is specified to be
completely asynchronous with respect to CK and CK#.
Therefore, no timing relationship can be guaranteed between
the two. When entering reset, the register will be cleared and
the outputs will be driven low quickly, relative to the time to
disable the differential input receivers. However, when coming
out of reset, the register will become active quickly, relative to
the time to enable the differential input receivers.
Description
All clock and data inputs are compatible with the JEDEC
standard for SSTL_18. The control inputs are LVCMOS. All
outputs are 1.8-V CMOS drivers that have been optimized to
drive the DDR-II DIMM load. The SSTU32864 operates from
a differential clock (CK and CK#). Data are registered at the
crossing of CK going high, and CK# going low.
The C0 input controls the pinout configuration of the 1:2 pinout
from A configuration (when low) to B configuration (when
high). The C1 input controls the pinout configuration from
25-bit 1:1 (when low) to 14-bit 1:2 (when high). C0 = 1 and
C1 = 0 is not allowed and should default to the C0 = C1 = 0
state.
Block Diagram
Pin Configuration
Cypress Semiconductor Corporation
Document #: 38-07576 Rev. **
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3901 North First Street
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San Jose
,
CA 95134
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408-943-2600
Revised September 9, 2003
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