Maxim Integrated DS33R11 - Manual (Page 314)

DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver
314 of 344
13.1 Thermal Characteristics
Table 13-3. Thermal Characteristics
PARAMETER MIN TYP MAX
Ambient Temperature (Note 1) -40°C +85°C
Junction Temperature (Note 2) +125°C
Theta-JA ( θ
JA
) in Still Air for 256-Pin
27mm BGA (Notes 2, 3)
+20.3°C/W
Note 1: The package is mounted on a four-layer JEDEC standard test board.
Note 2: Value guaranteed by design (GBD).
Note 3: Theta-JA ( θ
JA
) is the junction to ambient thermal resistance, when the package is mounted on a four-layer JEDEC
standard test board.
Table 13-4. Theta-JA vs. Airflow
AIR FLOW
THETA-JA
256-PIN (27mm) BGA
0m/s (Note 1) 20.3°C/W
1m/s (Note 1) 17.9°C/W
2.5m/s (Note 1) 16.9°C/W
Note 1: Value guaranteed by design (GBD).