5–20
Chapter 5: DC and Switching Characteristics
Timing Model and Specifications
Table 5–25.
EPM1270 Global Clock External I/O Timing Parameters (Part 2 of 2)
–3 Speed Grade
Symbol
t
CNT
Parameter
Minimum global clock
period for
16-bit counter
Maximum global clock
frequency for 16-bit
counter
Condition
—
Min
3.3
Max
—
–4 Speed Grade
Min
4.0
Max
—
–5 Speed Grade
Min
5.0
Max
—
Unit
ns
f
CNT
—
—
304.0
—
247.5
—
201.1
MHz
Note to
(1) The maximum frequency is limited by the I/O standard on the clock input pin. The 16-bit counter critical delay performs faster than this global
clock input pin maximum frequency.
shows the external I/O timing parameters for EPM2210 devices.
Table 5–26.
EPM2210 Global Clock External I/O Timing Parameters
–3 Speed Grade
Symbol
t
PD1
Parameter
Worst case pin-to-pin delay
through 1 look-up table
(LUT)
Best case pin-to-pin delay
through 1 LUT
Global clock setup time
Global clock hold time
Global clock to output delay
Global clock high time
Global clock low time
Minimum global clock
period for
16-bit counter
Maximum global clock
frequency for 16-bit counter
Condition
10 pF
Min
—
Max
7.0
–4 Speed Grade
Min
—
Max
9.1
–5 Speed Grade
Min
—
Max
11.2
Unit
ns
t
PD2
t
SU
t
H
t
CO
t
CH
t
CL
t
CNT
10 pF
—
—
10 pF
—
—
—
—
1.2
0.0
2.0
166
166
3.3
3.7
—
—
4.6
—
—
—
—
1.5
0.0
2.0
216
216
4.0
4.8
—
—
6.0
—
—
—
—
1.9
0.0
2.0
266
266
5.0
5.9
—
—
7.4
—
—
—
ns
ns
ns
ns
ps
ps
ns
f
CNT
—
—
304.0
—
247.5
—
201.1
MHz
Note to
(1) The maximum frequency is limited by the I/O standard on the clock input pin. The 16-bit counter critical delay performs faster than this global
clock input pin maximum frequency.
ALTERA [ ALTERA CORPORATION ]
