ProASIC3L DC and Switching Characteristics
2-128
Revision 13
Global Tree Timing Characteristics
Global clock delays include the central rib delay, the spine delay, and the row delay. Delays do not
include I/O input buffer clock delays, as these are I/O standard–dependent, and the clock may be driven
and conditioned internally by the CCC module. For more details on clock conditioning capabilities, refer
present minimum and maximum global clock delays within each device. Minimum and maximum delays
are measured with minimum and maximum loading.
Timing Characteristics
Table 2-204 A3P250L Global Resource – Applies to 1.5 V DC Core Voltage
Commercial-Case Conditions: TJ = 70°C, VCC = 1.425 V
Parameter
Description
–1
Std.
Units
Min.1 Max.2 Min.1 Max.2
tRCKL
Input Low Delay for Global Clock
0.82
1.06
0.96
1.25
ns
tRCKH
Input High Delay for Global Clock
0.80
1.09
0.94
1.28
ns
tRCKMPWH
Minimum Pulse Width High for Global Clock
0.75
0.88
ns
tRCKMPWL
Minimum Pulse Width Low for Global Clock
0.85
1.00
ns
tRCKSW
Maximum Skew for Global Clock
0.29
0.34
ns
Notes:
1. Value reflects minimum load. The delay is measured from the CCC output to the clock pin of a sequential
element, located in a lightly loaded row (single element is connected to the global net).
2. Value reflects maximum load. The delay is measured on the clock pin of the farthest sequential element,
located in a fully loaded row (all available flip-flops are connected to the global net in the row).
3. For specific junction temperature and voltage supply levels, refer to Table 2-6 on page 2-7 for derating values.
Table 2-205 A3P250L Global Resource – Applies to 1.2 V DC Core Voltage
Commercial-Case Conditions: TJ = 70°C, VCC = 1.14 V
Parameter
Description
–1
Std.
Units
Min.1 Max.2 Min.1 Max.2
tRCKL
Input Low Delay for Global Clock
1.40
1.68
1.64
1.97
ns
tRCKH
Input High Delay for Global Clock
1.38
1.71
1.62
2.01
ns
tRCKMPWH
Minimum Pulse Width High for Global Clock
1.05
1.24
ns
tRCKMPWL
Minimum Pulse Width Low for Global Clock
1.23
1.44
ns
tRCKSW
Maximum Skew for Global Clock
0.33
0.39
ns
Notes:
1. Value reflects minimum load. The delay is measured from the CCC output to the clock pin of a sequential
element, located in a lightly loaded row (single element is connected to the global net).
2. Value reflects maximum load. The delay is measured on the clock pin of the farthest sequential element,
located in a fully loaded row (all available flip-flops are connected to the global net in the row).
3. For specific junction temperature and voltage supply levels, refer to Table 2-6 on page 2-7 for derating values.