OR3T125 Agere Systems, OR3T125 Datasheet - Page 195

• Manufacturer Part Number: OR3T125
• Description: 3C and 3T Field-Programmable Gate Arrays
• Manufacturer: Agere Systems

Data Sheet
June 1999
Lucent Technologies Inc.
Package Thermal Characteristics
FPGA Maximum Junction Temperature
Once the power dissipated by the FPGA has been determined (see the Estimating Power Dissipation section), the
maximum junction temperature of the FPGA can be found. This is needed to determine if speed derating of the
device from the 85 °C junction temperature used in all of the delay tables is needed. Using the maximum ambient
temperature, T
ture is approximated by:
Table 76 lists the plastic package thermal characteristics for the ORCA Series FPGAs.
Table 76. Plastic Package Thermal Characteristics for the ORCA Series
1. Mounted on 4-layer JEDEC standard test board with two power/ground planes.
2. With thermal balls connected to board ground plane.
3. Without thermal balls connected to board ground plane.
208-Pin SQFP
208-Pin SQFP2
240-Pin SQFP
240-Pin SQFP2
256-Pin PBGA
256-Pin PBGA
352-Pin PBGA
352-Pin PBGA
432-Pin EBGA
600-Pin EBGA
Package
Amax
1
1
1, 2
1, 3
1, 2
1, 3
1
1
1
1
, and the power dissipated by the device, Q (expressed in °C), the maximum junction tempera-
0 fpm
26.5
12.8
25.5
13.0
22.5
26.0
19.0
25.5
11.0
11.0
T
200 fpm
Jmax =
23.0
10.3
22.5
10.0
19.0
22.0
16.0
22.0
JA
(continued)
8.5
8.5
(°C/W)
T
Amax
+ (Q •
500 fpm
21.0
21.0
17.5
20.5
15.0
20.5
9.1
9.0
7.5
7.5
JA
)
ORCA Series 3C and 3T FPGAs
1
T
T
J
A
@ 0 fpm (W)
= 125 °C max
= 70 °C max
2.1
4.3
2.2
4.2
2.4
2.1
2.9
2.1
5.0
5.5
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