a2f500m3b-1csh484 Actel Corporation, a2f500m3b-1csh484 Datasheet - Page 43

• Manufacturer Part Number: a2f500m3b-1csh484
• Description: Actel
• Manufacturer: Actel Corporation

The length of time an I/O can withstand I
reliability data below is based on a 3.3 V, 12 mA I/O setting, which is the worst case for this type of
analysis.
For example, at 100°C, the short current condition would have to be sustained for more than 2200
operation hours to cause a reliability concern. The I/O design does not contain any short circuit
protection, but such protection would only be needed in extremely prolonged stress conditions.
Table 2-31 • Duration of Short Circuit Event before Failure
Table 2-32 • Schmitt Trigger Input Hysteresis
Table 2-33 • I/O Input Rise Time, Fall Time, and Related I/O Reliability
Temperature
–40°C
0°C
25°C
70°C
85°C
100°C
Input Buffer
LVTTL/LVCMOS
LVDS/B-LVDS/
M-LVDS/LVPEC
L
*
Input Buffer Configuration
3.3 V LVTTL / LVCMOS / PCI / PCI-X (Schmitt trigger mode)
2.5 V LVCMOS (Schmitt trigger mode)
1.8 V LVCMOS (Schmitt trigger mode)
1.5 V LVCMOS (Schmitt trigger mode)
The maximum input rise/fall time is related to the noise induced into the input buffer trace. If the noise is
low, then the rise time and fall time of input buffers can be increased beyond the maximum value. The
longer the rise/fall times, the more susceptible the input signal is to the board noise. Actel recommends
signal integrity evaluation/characterization of the system to ensure that there is no excessive noise
coupling into input signals.
Hysteresis Voltage Value (typical) for Schmitt Mode Input Buffers
Input Rise/Fall Time (min.)
No requirement
No requirement
OSH
R e v i s i o n 3
/I
OSL
Input Rise/Fall Time (max.)
events depends on the junction temperature. The
Actel SmartFusion Intelligent Mixed Signal FPGAs
Time before Failure
10 ns *
10 ns *
> 20 years
> 20 years
> 20 years
6 months
5 years
2 years
Hysteresis Value (typical)
240 mV
140 mV
80 mV
60 mV
20 years (100°C)
10 years (100°C)
Reliability
2- 31