Datasheet
ADSP-21160N
–42– REV. 0
Capacitive Loading
Output delays and holds are based on standard capacitive loads:
30 pF on all pins (see Figure 29). Figure 31 and Figure 32 show
how output rise time varies with capacitance. Figure 33 graphi-
cally shows how output delays and holds vary with load
capacitance. (Note that this graph or derating does not apply to
output disable delays; see Output Disable Time on Page 41.)
The graphs of Figure 31, Figure 32, and Figure 33 may not be
linear outside the ranges shown.
Environmental Conditions
The ADSP-21160NKB-100 and ADSP-21160NCB-100 are
provided in a 400-Ball Metric PBGA (Plastic Ball Grid Array)
package.
Thermal Characteristics
The ADSP-21160N is specified for a case temperature (
T
CASE
).
To ensure that the
T
CASE
data sheet specification is not exceeded,
a heatsink and/or an air flow source may be used. Use the cen-
terblock of ground pins (PBGA balls: F7-14, G7-14, H7-14,
J7-14, K7-14, L7-14, M-14, N7-14, P7-14, R7-15) to provide
thermal pathways to the printed circuit board’s ground plane. A
heatsink should be attached to the ground plane (as close as
possible to the thermal pathways) with a thermal adhesive.
• T
CASE
= Case temperature (measured on top surface
of package)
• PD = Power dissipation in W (this value depends upon
the specific application; a method for calculating PD is
shown under Power Dissipation).
•θ
CA
= Value from Table 31.
•θ
JB
= 6.46°C/W
Figure 31. Typical Output Rise Time (20%–80%,
V
DDEXT
= Max) vs. Load Capacitance
Figure 32. Typical Output Rise Time (20%–80%,
V
DDEXT
= Min) vs. Load Capacitance
LOAD CAPACITANCE – pF
0
0 25050 100 150 200
TBD
R
I
S
E
A
N
D
F
A
L
L
T
I
M
E
S
–
n
s
RISE TIME
FALL TIME
Y = 0.0751x +1.4882
Y = 0.0716x + 2.9043
2
4
6
8
10
12
14
16
18
20
LOAD CAPACITANCE – pF
20
0
0 25050 100 150 200
10
5
25
15
TBD
R
I
S
E
A
N
D
F
A
L
L
T
I
M
E
S
–
n
s
FALL TIME
Y = 0.0834x +1.0653
Y = 0.0813x +2.312
RISE TIME
Figure 33. Typical Output Delay or Hold vs. Load
Capacitance (at Max Case Temperature)
Table 31. Airflow Over Package Versus θ
CA
Airflow (Linear Ft./Min.) 0 200 400
θ
CA
(°C/W)
1
1
θ
JC
= 3.6 °C/W.
12.13 9.86 8.7
LOAD CAPACITANCE – pF
4
–2
025050 100 150 200
0
–4
6
2
O
U
T
P
U
T
D
E
L
A
Y
O
R
H
O
L
D
–
n
s
Y = 0.0716x – 3.9037
8
10
12
T
CASE
T
AMB
PD θ
CA
×()+=