ADSP-21061/ADSP-21061L
ENVIRONMENTAL CONDITIONS
9
8
Thermal Characteristics
The ADSP-21061KS (5 V) device is packaged in a 240-lead
thermally enhanced MQFP. The top surface of the package
contains a copper slug from which most of the die heat is dissi-
pated. The slug is flush with the top surface of the package.
Note that the copper slug is internally connected to GND
through the device substrate. The ADSP-21061LKS is packaged
in a 240-lead MQFP without a copper heat slug. The ADSP-
21061L is also available in a 225-Ball PBGA package. The
PBGA has a θJC of 1.7°C/W. The ADSP-2106x is specified for a
case temperature (TCASE). To ensure that the TCASE data sheet
specification is not exceeded, a heatsink and/or an air flow
source may be used. A heatsink should be attached with a ther-
mal adhesive.
7
6
Y = 0.0391X + 0.36
5
4
RISE TIME
Y = 0.0305X + 0.24
3
2
1
0
FALL TIME
0
20
40
60
80 100 120 140 160 180 200
LOAD CAPACITANCE – pF
TCASE = TAMB + ( PD × θCA
)
Figure 33. Typical Output Rise Time (0.8 V–2.0 V) vs.
Load Capacitance (VDD = 3.3 V)
T
PD =
CASE = Case temperature (measured on top surface of package)
Power dissipation in W (this value depends upon the
specific application; a method for calculating PD is
shown under Power Dissipation).
5
θCA
=
Value from tables below.
4
3
2
1
Y = 0.0329X –1.65
ADSP-21061 (5 V MQFP Package)
JC = 0.3؇C/W
Airflow
(Linear Ft./Min.)
0
100
200
400
600
θCA (°C/W)
10
9
8
7
6
NOTES
This represents thermal resistance at total power of 5 W.
NOMINAL
With air flow, no variance is seen in θCA with power.
θCA at 0 LFM varies with power: at 2W, θCA = 14°C/W, at 3W θCA = 11°C/W.
–1
25
50
75
100
125
150
175
200
ADSP-21061L (3.3 V MQFP Package)
LOAD CAPACITANCE – pF
Figure 34. Typical Output Delay or Hold vs. Load Capaci-
tance (at Maximum Case Temperature) (VDD = 3.3 V)
JC = 6.3؇C/W
Airflow
(Linear Ft./Min.)
0
100
200
400
600
θCA (°C/W)
19.6
17.6
15.6
13.9
12.2
NOTE
With air flow, no variance is seen in θCA with power.
ADSP-21061L (3.3 V PBGA Package)
JC = 1.7؇C/W
Airflow
(Linear Ft./Min.)
0
200
400
11.2
θCA (°C/W)
19.0
13.6
NOTE
With air flow, no variance is seen in θCA with power.
REV. B
–41–
ADI [ ADI ]
