Spartan-3AN FPGA Family: DC and Switching Characteristics
DS557 (v4.1) April 1, 2011
Product Specification
26
Pin-to-Pin Setup and Hold Times
Table 22: Pin-to-Pin Setup and Hold Times for the IOB Input Path (System Synchronous)
Symbol
Description
Conditions
Device
Speed Grade
Units
-5
-4
Min
Setup Times
TPSDCM
When writing to the Input
Flip-Flop (IFF), the time from the
setup of data at the Input pin to
the active transition at a Global
Clock pin. The DCM is in use. No
Input Delay is programmed.
IFD_DELAY_VALUE = 0,
XC3S50AN
2.45
2.68
ns
XC3S200AN
2.59
2.84
ns
XC3S400AN
2.38
2.68
ns
XC3S700AN
2.38
2.57
ns
XC3S1400AN
1.91
2.17
ns
TPSFD
When writing to IFF, the time from
the setup of data at the Input pin
to an active transition at the
Global Clock pin. The DCM is not
in use. The Input Delay is
programmed.
IFD_DELAY_VALUE = 5,
without DCM
XC3S50AN
2.55
2.76
ns
XC3S200AN
2.32
2.76
ns
XC3S400AN
2.21
2.60
ns
XC3S700AN
2.28
2.63
ns
XC3S1400AN
2.33
2.41
ns
Hold Times
TPHDCM
When writing to IFF, the time from
the active transition at the Global
Clock pin to the point when data
must be held at the Input pin. The
DCM is in use. No Input Delay is
programmed.
IFD_DELAY_VALUE = 0,
XC3S50AN
–0.36
ns
XC3S200AN
–0.52
ns
XC3S400AN
–0.33
–0.29
ns
XC3S700AN
–0.17
–0.12
ns
XC3S1400AN
–0.07
0.00
ns
TPHFD
When writing to IFF, the time from
the active transition at the Global
Clock pin to the point when data
must be held at the Input pin. The
DCM is not in use. The Input
Delay is programmed.
IFD_DELAY_VALUE = 5,
without DCM
XC3S50AN
–0.63
–0.58
ns
XC3S200AN
–0.56
ns
XC3S400AN
–0.42
ns
XC3S700AN
–0.80
–0.75
ns
XC3S1400AN
–0.69
ns
Notes:
1.
The numbers in this table are tested using the methodology presented in
Table 30 and are based on the operating conditions set forth in
2.
This setup time requires adjustment whenever a signal standard other than LVCMOS25 is assigned to the Global Clock Input or the data
Input. If this is true of the Global Clock Input, subtract the appropriate adjustment from
Table 26. If this is true of the data Input, add the
appropriate Input adjustment from the same table.
3.
This hold time requires adjustment whenever a signal standard other than LVCMOS25 is assigned to the Global Clock Input or the data
Input. If this is true of the Global Clock Input, add the appropriate Input adjustment from
Table 26. If this is true of the data Input, subtract the
appropriate Input adjustment from the same table. When the hold time is negative, it is possible to change the data before the clock’s active
edge.
4.
DCM output jitter is included in all measurements.