Справочник Пользователя для Hynix HMT325U7CFR8C-PBT0
Rev. 1.2 / Jul. 2013
6
Input/Output Functional Descriptions
Symbol
Type
Polarity
Function
CK0–CK1
CK0–CK1
CK0–CK1
SSTL
Differential
crossing
CK and CK are differential clock inputs. All the DDR3 SDRAM addr/cntl
inputs are sampled on the crossing of positive edge of CK and negative
edge of CK. Output (read) data is reference to the crossing of CK and CK
(Both directions of crossing).
inputs are sampled on the crossing of positive edge of CK and negative
edge of CK. Output (read) data is reference to the crossing of CK and CK
(Both directions of crossing).
CKE0–CKE1
SSTL
Active High
Activates the SDRAM CK signal when high and deactivates the CK signal
when low. By deactivating the clocks, CKE low initiates the Power Down
mode, or the Self Refresh mode.
when low. By deactivating the clocks, CKE low initiates the Power Down
mode, or the Self Refresh mode.
S0–S1
SSTL
Active Low
Enables the associated SDRAM command decoder when low and disables
the command decoder when high. When the command decoder is dis-
abled, new commands are ignored but previous operations continue. This
signal provides for external rank selection on systems with multiple ranks.
the command decoder when high. When the command decoder is dis-
abled, new commands are ignored but previous operations continue. This
signal provides for external rank selection on systems with multiple ranks.
RAS, CAS, WE
SSTL
Active Low RAS, CAS, and WE (
ALONG
WITH
S) define the command being entered.
ODT0–ODT1
SSTL
Active High
When high, termination resistance is enabled for all DQ, DQS, DQS and DM
pins, assuming this function is enabled in the Mode Register 1 (MR1).
pins, assuming this function is enabled in the Mode Register 1 (MR1).
V
REF
DQ
Supply
Reference voltage for SSTL15 I/O inputs.
V
REF
CA
Supply
Reference voltage for SSTL 15 command/address inputs.
V
DD
Q
Supply
Power supply for the DDR3 SDRAM output buffers to provide improved
noise immunity. For all current DDR3 unbuffered DIMM designs, V
noise immunity. For all current DDR3 unbuffered DIMM designs, V
DD
Q
shares the same power plane as V
DD
pins.
BA0–BA2
SSTL
—
Selects which SDRAM bank of eight is activated.
A0–A15
SSTL
—
During a Bank Activate command cycle, Address input defines the row
address (RA0–RA15).
During a Read or Write command cycle, Address input defines the column
address. In addition to the column address, AP is used to invoke autopre-
charge operation at the end of the burst read or write cycle. If AP is high,
autoprecharge is selected and BA0, BA1, BA2 defines the bank to be pre-
charged. If AP is low, autoprecharge is disabled. During a Precharge com-
mand cycle, AP is used in conjunction with BA0, BA1, BA2 to control which
bank(s) to precharge. If AP is high, all banks will be precharged regardless
of the state of BA0, BA1 or BA2. If AP is low, BA0, BA1 and BA2 are used to
define which bank to precharge. A12(BC) is sampled during READ and
WRITE commands to determine if burst chop (on-the-fly) will be per-
formed (HIGH, no burst chop; LOW, burst chopped).
address (RA0–RA15).
During a Read or Write command cycle, Address input defines the column
address. In addition to the column address, AP is used to invoke autopre-
charge operation at the end of the burst read or write cycle. If AP is high,
autoprecharge is selected and BA0, BA1, BA2 defines the bank to be pre-
charged. If AP is low, autoprecharge is disabled. During a Precharge com-
mand cycle, AP is used in conjunction with BA0, BA1, BA2 to control which
bank(s) to precharge. If AP is high, all banks will be precharged regardless
of the state of BA0, BA1 or BA2. If AP is low, BA0, BA1 and BA2 are used to
define which bank to precharge. A12(BC) is sampled during READ and
WRITE commands to determine if burst chop (on-the-fly) will be per-
formed (HIGH, no burst chop; LOW, burst chopped).
DQ0–DQ63,
CB0–CB7
SSTL
—
Data and Check Bit Input/Output pins.
DM0–DM8
SSTL
Active High
DM is an input mask signal for write data. Input data is masked when DM
is sampled High coincident with that input data during a write access. DM
is sampled on both edges of DQS. Although DM pins are input only, the DM
loading matches the DQ and DQS loading.
is sampled High coincident with that input data during a write access. DM
is sampled on both edges of DQS. Although DM pins are input only, the DM
loading matches the DQ and DQS loading.
V
DD
, V
SS
Supply
Power and ground for the DDR3 SDRAM input buffers, and core logic. V
DD
and V
DD
Q pins are tied to V
DD
/V
DD
Q planes on these modules.