DC & Switching Characteristics
Table 5–17. SSTL-18 Class II Specifications
Symbol
VCCIO
VREF
Parameter
Output supply voltage
Reference voltage
Termination voltage
Conditions
Minimum
1.71
Typical
1.80
Maximum Unit
1.89
0.945
V
V
V
V
V
V
V
V
V
0.855
0.900
VREF
VTT
VREF – 0.04
VREF + 0.125
VREF + 0.04
V
V
V
V
IH (DC) High-level DC input voltage
IL (DC) Low-level DC input voltage
IH (AC) High-level AC input voltage
IL (AC) Low-level AC input voltage
VREF – 0.125
VREF – 0.25
0.28
VREF + 0.25
VOH
VOL
High-level output voltage
Low-level output voltage
IOH = –13.4 mA (1) VCCIO – 0.28
IOL = 13.4 mA (1)
Note to Table 5–17:
(1) This specification is supported across all the programmable drive settings available for this I/O standard as shown
in the Stratix II Architecture chapter in volume 1 of the Stratix II Device Handbook.
Table 5–18. SSTL-18 Class I & II Differential Specifications
Symbol
Parameter
Conditions
Minimum
1.71
Typical
Maximum
Unit
V
VCCIO
Output supply voltage
1.80
1.89
VSWING DC differential input voltage
(DC)
0.25
V
VX (AC) AC differential input cross
point voltage
(VCCIO/2) – 0.175
0.5
(VCCIO/2) + 0.175
V
V
VSWING AC differential input voltage
(AC)
VISO
Input clock signal offset
voltage
0.5 × VCCIO
200
V
ΔVISO
Input clock signal offset
voltage variation
mV
V
VOX
(AC)
AC differential cross point
voltage
(VCCIO/2) – 0.125
(VCCIO/2) + 0.125
Altera Corporation
April 2011
5–11
Stratix II Device Handbook, Volume 1
ALTERA [ ALTERA CORPORATION ]
