EDJ8232B5MB Datasheet, PDF (19/142 Pages) Elpida Memory – 8G bits DDR3 SDRAM, DDP

EDJ8232B5MB
[Single-ended levels for CK, DQS, /CK, /DQS]
Parameter
Symbol min.
typ.
max.
Unit
Notes
Single-ended high level for strobes
Single-ended high level for CK, /CK
Single-ended low level for strobes
Single-ended low level for CK, /CK
VSEH
VSEL
(VDD/2)  0.175 
(VDD/2)  0.175 
*³

*³

*³
V
1, 2
*³
V
1, 2
(VDD/2)  0.175 V
1, 2
(VDD/2)  0.175 V
1, 2
Notes: 1. For CK, /CK use VIH/VIL(AC) of ADD/CMD; for strobes (DQS, /DQS) use VIH/VIL(AC) of DQs.
2. VIH(AC)/VIL(AC) for DQs is based on VREFDQ; VIH(AC)/VIL(AC) for address/command is based on
VREFCA; if a reduced ac-high or ac-low level is used for a signal group, then the reduced level applies
also here.
3. These values are not defined, however the single ended components of differential signals CK, /CK, DQS,
/DQS need to be within the respective limits (VIH(DC) max, VIL(DC)min) for single-ended signals as well
as the limitations for overshoot and undershoot. Refer to Overshoot and Undershoot specifications.
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 table below.
The differential input cross point voltage VIX is measured from the actual cross point of true and complement signal
to the midlevel between of VDD and VSS.
VDD
CK, DQS
VDD/2
/CK, /DQS
VSS
VSEH
VIX
VIX
VIX Definition
VIX
VSEL
[Cross point voltage for differential input signals (CK, DQS)]
Parameter
Symbol
pins
min.
max.
Unit Note
Differential input cross point voltage
relative to VDD/2
VIX
CK, /CK 150
150
175
175
mV
2
mV
1
VIX
DQS, /DQS 150
150
mV
2
Notes: 1. Extended range for VIX is only allowed for clock and if CK and /CK are monotonic, have a single-ended
swing VSEL/VSEH of at least VDD/2 +/-250 mV, and the differential slew rate of CK - /CK is larger than 3
V/ ns. Refer to the table of Single-ended levels for CK, DQS, /CK, /DQS for VSEL and VSEH standard
values.
2. The relation between VIX min./max. and VSEL/VSEH should satisfy following.
(VDD/2) + VIX (min.)  VSEL ≥ 25mV
VSEH  ((VDD/2) + VIX (max.)) ≥ 25mV
Data Sheet E1825E30 (Ver. 3.0)
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