28
80960MC
3.3
Package Thermal Specification
The 80960MC is specified for operation when case
temperature is within the range 0°C to 85°C (PGA).
Measure case temperature at the top center of the
package. Ambient temperature can be calculated
from:
•
T
J
= T
C
+ P*
θ
jc
•
T
A
= T
J
+ P*
θ
ja
•
T
C
= T
A
+ P*
[θ
ja
−θ
jc
]
Values for
θ
ja
and
θ
jc
for various airflows are given in
Table 10
for the PGA package. The PGA’s
θ
ja
can
be reduced by adding a heatsink.
Maximum allowable ambient temperature (T
A
)
permitted without exceeding T
C
is shown by the
graphs in
Figure 23
,
Figure 24
and
Figure 25
. The
curves assume the maximum permitted supply
current (I
CC
) at each speed, V
CC
of +5.0 V and a
T
CASE
of +85° C (PGA).
Table 10. 80960MC PGA Package Thermal Characteristics
Thermal Resistance — °C/Watt
Parameter
Airflow — ft./min (m/sec)
0
(0)
50
(0.25)
100
(0.50)
200
(1.01)
400
(2.03)
600
(3.04)
800
(4.06)
θ
Junction-to-Case
2
2
2
2
2
2
2
θ
Case-to-Ambient
(No Heatsink)
19
18
17
15
12
10
9
θ
Case-to-Ambient
(Omnidirectional
Heatsink)
16
15
14
12
9
7
6
θ
Case-to-Ambient
(Unidirectional
Heatsink)
15
14
13
11
8
6
5
NOTES:
1. This table applies to 80960MC PGA plugged into socket or soldered directly to board.
2.
θ
JA
=
θ
JC
+
θ
CA
3.
θ
J-CAP
= 4°C/W (approx.)
θ
J-PIN
= 4°C/W (inner pins) (approx.)
θ
J-PIN
= 8°C/W (outer pins) (approx.)
θ
JC
θ
JA
θ
J-PIN
θ
J-CAP
