Samsung M471B1G73AH0 - Manual (Page 14)

- 14 -
Unbuffered SODIMM
datasheet
DDR3 SDRAM
Rev. 1.0
10.3.4 Differential Input Cross Point Voltage
To guarantee tight setup and hold times as well as output skew parameters with respect to clock and strobe, each cross point voltage of differential input
signals (CK, CK and DQS, DQS) must meet the requirements in below table. The differential input cross point voltage V
IX
is measured from the actual
cross point of true and complement signal to the mid level between of V
DD
and V
SS
.
Figure 4. V
IX
Definition
[ Table 5 ] Cross point voltage for differential input signals (CK, DQS)
NOTE :
1. Extended range for V
IX
is only allowed for clock and if single-ended clock input signals CK and CK are monotonic, have a single-ended swing V
SEL
/ V
SEH
of at least V
DD
/2
±250 mV, and the differential slew rate of CK-CK is larger than 3 V/ ns.
10.4 Slew Rate Definition for Single Ended Input Signals
See "Address / Command Setup, Hold and Derating" for single-ended slew rate definitions for address and command signals.
See "Data Setup, Hold and Slew Rate Derating" for single-ended slew rate definitions for data signals.
10.5 Slew rate definition for Differential Input Signals
Input slew rate for differential signals (CK, CK and DQS, DQS) are defined and measured as shown in below.
[ Table 6 ] Differential input slew rate definition
NOTE : The differential signal (i.e. CK - CK and DQS - DQS) must be linear between these thresholds
Figure 5. Differential input slew rate definition for DQS, DQS and CK, CK
Symbol Parameter
DDR3-800/1066/1333/1600
Unit NOTE
Min Max
V
IX
Differential Input Cross Point Voltage relative to V
DD
/2 for CK,CK
-150 150 mV
-175 175 mV 1
V
IX
Differential Input Cross Point Voltage relative to V
DD
/2 for DQS,DQS -150 150 mV
Description
Measured
Defined by
From To
Differential input slew rate for rising edge (CK-CK and DQS-DQS) V
ILdiffmax
V
IHdiffmin
V
IHdiffmin
- V
ILdiffmax
Delta TRdiff
Differential input slew rate for falling edge (CK-CK and DQS-DQS) V
IHdiffmin
V
ILdiffmax
V
IHdiffmin
- V
ILdiffmax
Delta TFdiff
V
DD
CK, DQS
V
DD
/2
CK, DQS
V
SS
V
IX
V
IX
V
IX
V
IHdiffmin
0
V
ILdiffmax
delta TRdiff delta TFdiff