SX-A Family FPGAs
2- 6
v5.3
Table 2-10 AC Specifications (3.3 V PCI Operation)
Symbol
Parameter
Condition
Min.
Max.
Units
IOH(AC)
Switching Current High
0 < VOUT ≤ 0.3VCCI
1
–12VCCI
–mA
0.3VCCI ≤ VOUT < 0.9VCCI
1
(–17.1(VCCI – VOUT))
–
mA
0.7VCCI < VOUT < VCCI
1, 2
–
–
(Test Point)
VOUT = 0.7VCC
2
––32VCCI
mA
Switching Current Low
VCCI > VOUT ≥ 0.6VCCI
1
16VCCI
–mA
0.6VCCI > VOUT > 0.1VCCI
1
(26.7VOUT)–
mA
0.18VCCI > VOUT > 0
1, 2
–
–
(Test Point)
VOUT = 0.18VCC
2
–
38VCCI
mA
ICL
Low Clamp Current
–3 < VIN ≤ –1
–25 + (VIN + 1)/0.015
–
mA
ICH
High Clamp Current
VCCI + 4 > VIN ≥ VCCI + 1
25 + (VIN – VCCI – 1)/0.015
–
mA
slewR
Output Rise Slew Rate
0.2VCCI - 0.6VCCI load
3
14
V/ns
slewF
Output Fall Slew Rate
0.6VCCI - 0.2VCCI load
3
14
V/ns
Notes:
1. Refer to the V/I curves in Figure 2-2 on page 2-7. Switching current characteristics for REQ# and GNT# are permitted to be one half of that specified here; i.e., half size output drivers may be used on these signals. This specification does not apply to CLK and RST#,
which are system outputs. “Switching Current High” specifications are not relevant to SERR#, INTA#, INTB#, INTC#, and INTD#,
which are open drain outputs.
2. Maximum current requirements must be met as drivers pull beyond the last step voltage. Equations defining these maximums (C
and D) are provided with the respective diagrams in Figure 2-2 on page 2-7. The equation defined maximum should be met by design. In order to facilitate component testing, a maximum current test point is defined for each side of the output driver.
3. This parameter is to be interpreted as the cumulative edge rate across the specified range, rather than the instantaneous rate at any
point within the transition range. The specified load (diagram below) is optional; i.e., the designer may elect to meet this parameter
with an unloaded output per the latest revision of the PCI Local Bus Specification. However, adherence to both maximum and
minimum parameters is required (the maximum is no longer simply a guideline). Rise slew rate does not apply to open drain
outputs.
Output
Buffer
1/2 in. max.
10 pF
Pin
1 k/25
Ω
1 k/25
Ω
Pin
Buffer
Output
10 pF