1–10
Chapter 1: Cyclone III Device Data Sheet
Electrical Characteristics
Internal Weak Pull-Up and Weak Pull-Down Resistor
Table 1–10 lists the weak pull-up and pull-down resistor values for Cyclone III
devices.
Table 1–10. Cyclone III Devices Internal Weak Pull-Up and Weak Pull-Down Resistor (Note 1)
Symbol
Parameter
Conditions
Min
7
Typ
25
28
35
57
82
143
19
22
25
35
50
Max
41
Unit
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
kΩ
V
CCIO = 3.3 V 5% (2), (3)
VCCIO = 3.0 V 5% (2), (3)
VCCIO = 2.5 V 5% (2), (3)
VCCIO = 1.8 V 5% (2), (3)
VCCIO = 1.5 V 5% (2), (3)
VCCIO = 1.2 V 5% (2), (3)
7
47
Value of I/O pin pull-up resistor before
and during configuration, as well as
user mode if the programmable
pull-up resistor option is enabled
8
61
R_PU
10
13
19
6
108
163
351
30
V
CCIO = 3.3 V 5% (4)
VCCIO = 3.0 V 5% (4)
VCCIO = 2.5 V 5% (4)
VCCIO = 1.8 V 5% (4)
VCCIO = 1.5 V 5% (4)
6
36
Value of I/O pin pull-down resistor
before and during configuration
R_PD
6
43
7
71
8
112
Notes to Table 1–10:
(1) All I/O pins have an option to enable weak pull-up except configuration, test, and JTAG pin. Weak pull-down feature is only available for JTAG
TCK.
(2) Pin pull-up resistance values may be lower if an external source drives the pin higher than VCCIO
.
(3) R_P U = (VCCIO – VI)/IR_PU
Minimum condition: –40°C; VCCIO = VCC + 5%, VI = VCC + 5% – 50 mV;
Typical condition: 25°C; VCCIO = VCC, VI = 0 V;
Maximum condition: 125°C; VCCIO = VCC – 5%, VI = 0 V; in which V refers to the input voltage at the I/O pin.
I
(4) R_P D = V/IR_PD
I
Minimum condition: –40°C; VCCIO = VCC + 5%, VI = 50 mV;
Typical condition: 25°C; VCCIO = VCC, VI = VCC – 5%;
Maximum condition: 125°C; VCCIO = VCC – 5%, VI = VCC – 5%; in which VI refers to the input voltage at the I/O pin.
Hot Socketing
Table 1–11 lists the hot-socketing specifications for Cyclone III devices.
Table 1–11. Cyclone III Devices Hot-Socketing Specifications
Symbol
Parameter
Maximum
300 μA
IIOPIN(DC)
IIOPIN(AC)
DC current per I/O pin
AC current per I/O pin
8 mA (1)
Note to Table 1–11:
(1) The I/O ramp rate is 10 ns or more. For ramp rates faster than 10 ns, |IIOPIN| = C
dv/dt, in which C is I/O pin capacitance and dv/dt is the slew rate.
Schmitt Trigger Input
Cyclone III devices support Schmitt trigger input on 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 signal with
slow edge rate. Table 1–12 lists the hysteresis specifications across supported VCCIO
range for Schmitt trigger inputs in Cyclone III devices.
Cyclone III Device Handbook, Volume 2
© January 2010 Altera Corporation
ALTERA [ ALTERA CORPORATION ]
