M1AFS600-PQ208 Datasheet, PDF (257/334 Pages) Microsemi Corporation – Fusion Family of Mixed Signal FPGAs

Fusion Family of Mixed Signal FPGAs
Thermal Characteristics
Introduction
The temperature variable in the Microsemi Designer software refers to the junction temperature, not the
ambient, case, or board temperatures. This is an important distinction because dynamic and static power
consumption will cause the chip's junction temperature to be higher than the ambient, case, or board
temperatures. EQ 1 through EQ 3 give the relationship between thermal resistance, temperature
gradient, and power.
_JA = -^T---^J----_P^{–-----}---^A--
_JB = ^T----^J----_P^–-----T----^B-
EQ 1
_JC = ^T----^J----–_P-----^T----^C-
where
_JA = Junction-to-air thermal resistance
_JB = Junction-to-board thermal resistance
_JC = Junction-to-case thermal resistance
T_J = Junction temperature
T_A = Ambient temperature
T_B = Board temperature (measured 1.0 mm away from the
package edge)
T_C = Case temperature
P = Total power dissipated by the device
EQ 2
EQ 3
Table 3-6 • Package Thermal Resistance
Product
AFS090-QN108
AFS090-QN180
AFS250-QN180
AFS250-PQ208
AFS600-PQ208
AFS090-FG256
AFS250-FG256
AFS600-FG256
AFS1500-FG256
AFS600-FG484
AFS1500-FG484
AFS1500-FG676
Still Air
34.5
33.3
32.2
42.1
23.9
37.7
33.7
28.9
23.3
21.8
21.6
TBD
_JA
1.0 m/s
30.0
27.6
26.5
38.4
21.3
33.9
30.0
25.2
19.6
18.2
16.8
TBD
2.5 m/s
27.7
25.7
24.7
37
20.48
32.2
28.3
23.5
18.0
16.7
15.2
TBD
_JC
8.1
9.2
5.7
20.5
6.1
11.5
9.3
6.8
4.3
7.7
5.6
TBD
_JB
16.7
21.2
15.0
36.3
16.5
29.7
24.8
19.9
14.2
16.8
14.9
TBD
Units
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
Revision 4
3-7