Datasheet

SM646UDR26485-2-I
January 31, 2006
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17
Capacitance
(V
DD
= 1.8V±0.1V, T
Case
= +25°C)
Parameter Symbol Min Max Unit
Input Capacitance (CKn, CKn#) C
CK
3.0 6.0 pF
Input Capacitance delta (CKn, CKn#) C
DCK
-0.75pF
Input Capacitance (all other input-only pins) C
I
8.0 16.0 pF
Input Capacitance delta (all other input-only pins) C
DI
-2.0pF
Input/Output Capacitance (DQ, DM, DQS, DQS#) C
I0
2.5 3.5 pF
Input/Output Capacitance delta (DQ, DM, DQS, DQS#) C
DI0
-0.5pF
AC Operating Conditions
(V
DD
= 1.8V±0.1V, V
SS
= 0V)
Notes:
1. Input slew rate is 1V/ns.
2. Inputs are not recognized as valid until V
REF
stabilizes.
3. V
ID
is the magnitude of the difference between the input level on CK and the input level on CK#.
4. The value of V
IX
/V
OX
is expected to equal 0.5*V
DDQ
of the transmitting device and must track variations in the
DC level of the same.
Parameter Symbol Min Max Unit Notes
Input High Logic Voltage V
IH(AC)
V
REF
+ 0.250 - V 1, 2
Input Low Logic Voltage V
IL(AC)
-V
REF
- 0.250 V 1, 2
Input differential voltage, CK and CK#
inputs
V
ID(AC)
0.5 V
DDQ
+ 0.6 V 1, 2, 3
Input crossing point voltage, CK and
CK# inputs
V
IX(AC)
0.5*V
DDQ
- 0.175 0.5*V
DDQ
+ 0.175 V 1, 2, 3
AC differential crossing point voltage V
OX(AC)
0.5*V
DDQ
- 0.125 0.5*V
DDQ
+ 0.125 V 3