AS4C256M8D3
DM
Input
Data Input Mask: Input data is masked when DM is sampled HIGH during a write cycle.
DM has an optional use as TDQS on the x8.
DQ0 – DQ7 Input /
Data I/O: The DQ0-DQ7 input and output data are synchronized with positive and negative
Output
edges of DQS and DQS#. The I/Os are byte-maskable during Writes.
ODT
Input
On Die Termination: ODT (registered HIGH) enables termination resistance internal to
the DDR3 SDRAM. When enabled, ODT is applied to each DQ, DQS, DQS#, DM/TDQS
and TDQS# signal. (When TDQS is enabled via Mode Register A11=1 in MR1) The ODT
pin will be ignored if Mode-registers, MR1and MR2, are programmed to disable RTT.
RESET#
Input
Active Low Asynchronous Reset: Reset is active when RESET# is LOW, and inactive
when RESET# is HIGH. RESET# must be HIGH during normal operation. RESET# is a
CMOS rail to rail signal with DC high and low at 80% and 20% of VDD
VDD
VSS
Supply
Supply
Supply
Supply
Power Supply: +1.5V 0.075V
Ground
VDDQ
VSSQ
VREFCA
VREFDQ
ZQ
DQ Power: +1.5V 0.075V.
DQ Ground
Supply Reference voltage for CA
Supply Reference voltage for DQ
Supply Reference pin for ZQ calibration.
NC
-
No Connect: These pins should be left unconnected.
Confidential
7
Rev. 3.0
Aug. /2014