
Device Architecture
2-174
Revision 4
Applicable to Standard I/O Banks
3.3 V LVTTL / 3.3 V LVCMOS
2 mA
100
300
4 mA
100
300
6 mA
50
150
8 mA
50
150
2.5 V LVCMOS
2 mA
100
200
4 mA
100
200
6 mA
50
100
8 mA
50
100
1.8 V LVCMOS
2 mA
200
225
4 mA
100
112
1.5 V LVCMOS
2 mA
200
224
Table 2-97 I/O Weak Pull-Up/Pull-Down Resistances
Minimum and Maximum Weak Pull-Up/Pull-Down Resistance Values
VCCI
R(WEAK PULL-UP)1
(ohms)
R(WEAK PULL-DOWN)2
(ohms)
Min.
Max.
Min.
Max.
3.3 V
10 k
45 k
10 k
45 k
2.5 V
11 k
55 k
12 k
74 k
1.8 V
18 k
70 k
17 k
110 k
1.5 V
19 k
90 k
19 k
140 k
Notes:
1. R(WEAK PULL-UP-MAX) = (VCCImax – VOHspec) / IWEAK PULL-UP-MIN
2. R(WEAK PULL-DOWN-MAX) = VOLspec / IWEAK PULL-DOWN-MIN
Table 2-96 I/O Output Buffer Maximum Resistances 1 (continued)
Standard
Drive Strength
RPULL-DOWN
(ohms) 2
RPULL-UP
(ohms) 3
Notes:
1. These maximum values are provided for informational reasons only. Minimum output buffer resistance values depend
on VCC, drive strength selection, temperature, and process. For board design considerations and detailed output buffer
resistances, use the corresponding IBIS models located on the Microsemi SoC Products Group website:
http://www.microsemi.com/soc/techdocs/models/ibis.html.
2. R(PULL-DOWN-MAX) = VOLspec / IOLspec
3. R(PULL-UP-MAX) = (VCCImax – VOHspec) / IOHspec