Cyclone FPGA Family Data Sheet
Preliminary Information
The Cyclone VCCINT pins must always be connected to a 1.5-V power
supply. If the VCCINT level is 1.5 V, then input pins are 1.5-V, 1.8-V, 2.5-V,
and 3.3-V tolerant. The VCCIO pins can be connected to either a 1.5-V,
1.8-V, 2.5-V, or 3.3-V power supply, depending on the output
requirements. The output levels are compatible with systems of the same
voltage as the power supply (i.e., when VCCIO pins are connected to a
1.5-V power supply, the output levels are compatible with 1.5-V systems).
When VCCIO pins are connected to a 3.3-V power supply, the output high
is 3.3 V and is compatible with 3.3-V or 5.0-V systems. Table 17
summarizes Cyclone MultiVolt I/O support.
Table 17. Cyclone MultiVolt I/O Support
Note (1)
VCCIO (V)
Input Signal
Output Signal
1.5 V 1.8 V 2.5 V 3.3 V 5.0 V 1.5 V 1.8 V 2.5 V 3.3 V 5.0 V
1.5
1.8
2.5
3.3
v
v
v
v (2) v (2)
v
v (3)
v
v
v
v
v
v
v (5) v (5)
v
v (4)
v (6) v (7) v (7) v (7)
v
v (8)
Notes to Table 17:
(1) The PCI clamping diode must be disabled to drive an input with voltages higher than V
.
CCIO
(2) When V
(3) When V
(4) When V
= 1.5 V and a 2.5- or 3.3-V input signal feeds an input pin, higher pin leakage current is expected.
= 1.8 V, a Cyclone device can drive a 1.5-V device with 1.8-V tolerant inputs.
CCIO
CCIO
CCIO
= 3.3 V and a 2.5-V input signal feeds an input pin, the V
supply current will be slightly larger
CCIO
than expected.
(5) When V = 2.5 V, a Cyclone device can drive a 1.5-V or 1.8-V device with 2.5-V tolerant inputs.
CCIO
(6) Cyclone devices can be 5.0-V tolerant with the use of an external resistor and the internal PCI clamp diode.
(7) When V
(8) When V
= 3.3 V, a Cyclone device can drive a 1.5-V, 1.8-V, or 2.5-V device with 3.3-V tolerant inputs.
= 3.3 V, a Cyclone device can drive a device with 5.0-V LVTTL inputs but not 5.0-V LVCMOS inputs.
CCIO
CCIO
Because Cyclone devices can be used in a mixed-voltage environment,
they have been designed specifically to tolerate any possible power-up
sequence. Therefore, the VCCIO and VCCINT power supplies may be
powered in any order.
Power
Sequencing &
Hot Socketing
Signals can be driven into Cyclone devices before and during power up
without damaging the device. In addition, Cyclone devices do not drive
out during power up. Once operating conditions are reached and the
device is configured, Cyclone devices operate as specified by the user.
All Cyclone devices provide JTAG BST circuitry that complies with the
IEEE Std. 1149.1a-1990 specification. JTAG boundary-scan testing can be
performed either before or after, but not during configuration. Cyclone
devices can also use the JTAG port for configuration together with either
the Quartus II software or hardware using either Jam Files (.jam) or Jam
Byte-Code Files (.jbc).
IEEE Std.
1149.1 (JTAG)
Boundary Scan
Support
60
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