Datasheet

AC and DC Input Measurement Levels
Table 72. Single-Ended AC and DC Input Levels for Command and Address
Symbol
Parameter
DDR4-2400
DDR4-2666
Unit
Note
Min.
Max.
Min.
Max.
V
IH.CA(DC75)
DC input logic high
V
REFCA
+
0.075
V
DD
TBD
TBD
V
V
IL.CA(DC75)
DC input logic low
V
SS
V
REFCA
-
0.075
TBD
TBD
V
V
IH.CA(AC100)
AC input logic high
V
REF
+
0.1
V
DD
TBD
TBD
V
1
V
IL.CA(AC100)
AC input logic low
-
V
REF
-
0.1
TBD
TBD
V
1
V
REFCA(DC)
Reference Voltage for ADD, CMD inputs
0.49 x
V
DD
0.51 x
V
DD
TBD
TBD
V
2,3
Note 1. See “Overshoot and Undershoot Specifications”
Note 2. The AC peak noise on V
REFCA
may not allow V
REFCA
to deviate from V
REFCA(DC)
by more than ± 1% V
DD
(for
reference: approx. ± 12mV)
Note 3. For reference: approx. V
DD
/2 ± 12 mV
Differential swing requirements for clock (CK – CK#)
Table 73. Differential AC and DC Input Levels
Symbol
Parameter
Min.
Max.
Unit
Note
V
IHdiff
Differential input high
TBD
-
V
1,3
V
ILdiff
Differential input low
-
TBD
V
1,3
V
IHdiff(AC)
Differential input high ac
2 x (V
IH(AC)
- V
REF
)
-
V
2,3
V
ILdiff(AC)
Differential input low ac
-
2 x (V
IL(AC)
- V
REF
)
V
2,3
Note 1. Used to define a differential signal slew-rate.
Note 2. For CK - CK# use V
IH.CA
/V
IL.CA(AC)
of ADD/CMD and V
REFCA
;
Note 3. These values are not defined; however, the differential signals CK - CK#, need to be within the respective limits
(V
IH.CA(DC) max
, V
IL.CA(DC)min
) for single-ended signals as well as the limitations for overshoot and undershoot.
Single-ended requirements for differential signals
Table 74. Differential swing requirements for clock (CK – CK#)
Symbol
Parameter
Min.
Max.
Unit
Note
V
SEH
Single-ended high-level for CK, CK#
TBD
-
V
1-3
V
SEL
Single-ended low-level for CK, CK#
-
TBD
V
1-3
Note 1. For CK – CK# use V
IH.CA
/V
IL.CA(AC)
of ADD/CMD
Note 2. V
IH.CA
/V
IL.CA(AC)
for ADD/CMD is based on V
REFCA
Note 3. These values are not defined; however, the differential signals CK – CK#, need to be within the respective limits
(V
IH.CA(DC) max
, V
IL.CA(DC)min
) for single-ended signals as well as the limitations for overshoot and undershoot.
AS4C256M16D4
Confidential
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Rev.1.0 Aug.2019