EP20K400EBC652-1N Altera, EP20K400EBC652-1N Datasheet - Page 46

• Manufacturer Part Number: EP20K400EBC652-1N
• Description: APEX 20KE
• Manufacturer: Altera

APEX 20K Programmable Logic Device Family Data Sheet
MultiVolt I/O
Interface
46
Under hot socketing conditions, APEX 20KE devices will not sustain any
damage, but the I/O pins will drive out.
The APEX device architecture supports the MultiVolt I/O interface
feature, which allows APEX devices in all packages to interface with
systems of different supply voltages. The devices have one set of VCC pins
for internal operation and input buffers (VCCINT), and another set for I/O
output drivers (VCCIO).
The APEX 20K VCCINT pins must always be connected to a 2.5 V power
supply. With a 2.5-V V
tolerant. The VCCIO pins can be connected to either a 2.5-V or 3.3-V power
supply, depending on the output requirements. When VCCIO pins are
connected to a 2.5-V power supply, the output levels are compatible with
2.5-V systems. When the 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 12
Notes to
(1)
(2)
Open-drain output pins on 5.0-V tolerant APEX 20K devices (with a pull-
up resistor to the 5.0-V supply) can drive 5.0-V CMOS input pins that
require a V
to 5.0 V by the resistor. The open-drain pin will only drive low or tri-state;
it will never drive high. The rise time is dependent on the value of the pull-
up resistor and load impedance. The I
considered when selecting a pull-up resistor.
V
Table 12. 5.0-V Tolerant APEX 20K MultiVolt I/O Support
CCIO
2.5
3.3
The PCI clamping diode must be disabled to drive an input with voltages higher
than V
When V
tolerant inputs.
(V)
Table
summarizes 5.0-V tolerant APEX 20K MultiVolt I/O support.
CCIO
IH
CCIO
of 3.5 V. When the pin is inactive, the trace will be pulled up
12:
.
2.5
v
v
= 3.3 V, an APEX 20K device can drive a 2.5-V device with 3.3-V
Input Signals (V)
CCINT
v(1)
v
3.3
level, input pins are 2.5-V, 3.3-V, and 5.0-V
v(1)
v(1)
5.0
OL
current specification should be
v
v(2)
2.5
Output Signals (V)
Altera Corporation
3.3
v
5.0
v