1–12
Chapter 1: Cyclone IV Device Datasheet
Operating Conditions
December 2013
Altera Corporation
Schmitt Trigger Input
Cyclone IV devices support Schmitt trigger input on the TDI, TMS, TCK, nSTATUS,
nCONFIG
, nCE, CONF_DONE, and DCLK pins. A Schmitt trigger feature introduces
hysteresis to the input signal for improved noise immunity, especially for signals with
slow edge rate.
Table 1–14 lists the hysteresis specifications across the supported
VCCIO range for Schmitt trigger inputs in Cyclone IV devices.
I/O Standard Specifications
The following tables list input voltage sensitivities (VIH and VIL), output voltage (VOH
and VOL), and current drive characteristics (IOH and IOL), for various I/O standards
standard specifications for Cyclone IV devices.
Table 1–14. Hysteresis Specifications for Schmitt Trigger Input in Cyclone IV Devices
Symbol
Parameter
Conditions (V)
Minimum
Unit
VSCHMITT
Hysteresis for Schmitt trigger
input
VCCIO = 3.3
200
mV
VCCIO = 2.5
200
mV
VCCIO = 1.8
140
mV
VCCIO = 1.5
110
mV
Table 1–15. Single
-Ended I/O Standard Specifications for Cyclone IV Devices
(1), (2)I/O Standard
VCCIO (V)
VIL (V)
VIH (V)
VOL (V)
VOH (V)
IOL
(mA)
IOH
(mA)
Min
Typ
Max
Min
Max
Min
Max
Min
3.3
3.135
3.3
3.465
—
0.8
1.7
3.6
0.45
2.4
4
–4
3.3
3.135
3.3
3.465
—
0.8
1.7
3.6
0.2
VCCIO – 0.2
2
–2
3.0
2.85
3.0
3.15
–0.3
0.8
1.7
VCCIO + 0.3
0.45
2.4
4
–4
3.0
2.85
3.0
3.15
–0.3
0.8
1.7
VCCIO + 0.3
0.2
VCCIO – 0.2
0.1
–0.1
2.375
2.5
2.625
–0.3
0.7
1.7
VCCIO + 0.3
0.4
2.0
1
–1
1.8 V
1.71
1.8
1.89
–0.3
0.35 x
VCCIO
0.65 x
VCCIO
2.25
0.45
VCCIO –
0.45
2–2
1.5 V
1.425
1.5
1.575
–0.3
0.35 x
VCCIO
0.65 x
VCCIO
VCCIO + 0.3
0.25 x
VCCIO
0.75 x
VCCIO
2–2
1.2 V
1.14
1.2
1.26
–0.3
0.35 x
VCCIO
0.65 x
VCCIO
VCCIO + 0.3
0.25 x
VCCIO
0.75 x
VCCIO
2–2
3.0-V PCI
2.85
3.0
3.15
—
0.3 x
VCCIO
0.5 x
VCCIO
VCCIO + 0.3 0.1 x VCCIO
0.9 x VCCIO
1.5
–0.5
3.0-V PCI-X
2.85
3.0
3.15
—
0.35 x
VCCIO
0.5 x
VCCIO
VCCIO + 0.3 0.1 x VCCIO
0.9 x VCCIO
1.5
–0.5
(1) For voltage
(2) AC load CL = 10 pF
(3) For more information about interfacing Cyclone IV devices with 3.3/3.0/2.5
(4) To meet the IOL and IOH specifications, you must set the current strength settings accordingly. For example, to meet the 3.3-V LVTTL specification (4
mA), set the current strength settings to 4 mA or higher. Setting at lower current strength may not meet the IOL and IOH specifications in the handbook.