27
80960SA
3.4
Package Thermal Specifications
The 80960SA is specified for operation when case
temperature is within the range 0°C to +85°C (PLCC)
or 0°C to 100°C (QFP). Measure case temperature
at the top center of the package. Ambient temper-
ature 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
]
Compute P by multiplying the maximum voltage by
the typical current at maximum temperature. Values
for
θ
JA
and
θ
JC
for various airflows are given in Table
13 for the QFP package and in Table 14 for the
PLCC package. I
CC
at maximum temperature is
typically 80 percent of specified I
CC
maximum (cold).
Table 13. 80960SA QFP Package Thermal Characteristics
Thermal Resistance — °C/Watt
Parameter
Airflow — ft./min (m/sec)
0
50
100
200
400
600
800
θ
Junction-to-Ambient (Case
measured in the middle of the
top of the package)
(No Heatsink)
59
57
54
50
44
40
38
θ
Junction-to-Case
11
11
11
11
11
11
11
NOTES:
This table applies to 80960SA QFP soldered directly to board.
Table 14. 80960SA PLCC Package Thermal Characteristics
Thermal Resistance — °C/Watt
Parameter
Airflow — ft./min (m/sec)
0
50
100
200
400
600
800
1000
θ
Junction-to-Ambient
(No Heatsink)
34
32
29.5
28
25
23
21
20.5
θ
Junction-to-Case
12
12
12
12
12
12
12
12
NOTES:
This table applies to 80960SA PLCC soldered directly to board.
3.5
Stepping Register Information
Upon reset, register g0 contains die stepping infor-
mation. Table 15 shows the relationship between the
number in g0 and the current die stepping
The current numbering pattern in g0 may not be
consistent with past or future steppings of this
product.
Table 15. Die Stepping Cross Reference
Register g0
Die Stepping
01010101H
C-1
