ProASIC3 Flash Family FPGAs
Revision 13 2-21
Summary of I/O Timing Characteristics – Default I/O Software
Settings
Table 2-22 • Summary of AC Measuring Points
Standard Measuring Trip Point (V
trip
)
3.3 V LVTTL / 3.3 V LVCMOS 1.4 V
3.3 V LVCMOS Wide Range 1.4 V
2.5 V LVCMOS 1.2 V
1.8 V LVCMOS 0.90 V
1.5 V LVCMOS 0.75 V
3.3 V PCI 0.285 * VCCI (RR)
0.615 * VCCI (FF)
3.3 V PCI-X 0.285 * VCCI (RR)
0.615 * VCCI (FF)
Table 2-23 • I/O AC Parameter Definitions
Parameter Parameter Definition
t
DP
Data to Pad delay through the Output Buffer
t
PY
Pad to Data delay through the Input Buffer
t
DOUT
Data to Output Buffer delay through the I/O interface
t
EOUT
Enable to Output Buffer Tristate Control delay through the I/O interface
t
DIN
Input Buffer to Data delay through the I/O interface
t
HZ
Enable to Pad delay through the Output Buffer—High to Z
t
ZH
Enable to Pad delay through the Output Buffer—Z to High
t
LZ
Enable to Pad delay through the Output Buffer—Low to Z
t
ZL
Enable to Pad delay through the Output Buffer—Z to Low
t
ZHS
Enable to Pad delay through the Output Buffer with delayed enable—Z to High
t
ZLS
Enable to Pad delay through the Output Buffer with delayed enable—Z to Low