adsp-2165ks-80 Analog Devices, Inc., adsp-2165ks-80 Datasheet - Page 19

• Manufacturer Part Number: adsp-2165ks-80
• Description: Dsp Microcomputers With Rom
• Manufacturer: Analog Devices, Inc.

POWER DISSIPATION EXAMPLE
To determine total power dissipation in a specific application,
the following equation should be applied for each output:
C = load capacitance, f = output switching frequency.
Example:
In an ADSP-2162 application where external data memory is
used and no other outputs are active, power dissipation is calcu-
lated as follows:
Assumptions:
• External data memory is accessed every cycle with 50% of the
• External data memory writes occur every other cycle with
• Each address and data pin has a 10 pF total load at the pin.
• The application operates at V
P
(C
Output
Address, DMS 8
Data, WR
RD
CLKOUT
Total power dissipation for this example = P
ENVIRONMENTAL CONDITIONS
Ambient Temperature Rating:
Package
MQFP
REV. 0
ADSP-2162/ADSP-2164/ADSP-2166
address pins switching.
50% of the data pins switching.
T
T
PD = Power Dissipation in W
INT
CA
JA
JC
AMB
CASE
= internal power dissipation (from Figure 15).
= Thermal Resistance (Junction-to-Ambient)
= Thermal Resistance (Junction-to-Case)
V
= Thermal Resistance (Case-to-Ambient)
DD
= T
= Case Temperature in C
Total Power Dissipation = P
2
CASE
f) is calculated for each output:
– (PD
# of
Pins
9
1
1
60 C/W
JA
10 pF
10 pF
10 pF
10 pF
C
CA
C V
)
DD
DD
3.3
3.3
3.3
3.3
= 3.3 V and t
2
V
INT
DD
2
2
2
2
f
V
2
V
V
V
+ (C
18 C/W
JC
10 MHz = 8.71 mW
5 MHz = 4.90 mW
5 MHz = 0.55 mW
10 MHz = 1.09 mW
f
INT
V
CK
DD
+ 15.25 mW.
2
= 100 ns.
15.25 mW
f)
42 C/W
CA
–19–
CAPACITIVE LOADING
Figures 16 and 17 show capacitive loading characteristics for
the ADSP-2162 and ADSP-2164.
Figure 16. Typical Output Rise Time vs. Load Capaci-
tance, C
Figure 17. Typical Output Valid Delay or Hold vs. Load
Capacitance, C
Temperature)
NOMINAL
35
30
25
20
15
10
L
5
0
(at Maximum Ambient Operating Temperature)
0
10
–2
–4
8
6
4
2
0
L
25
(at Maximum Ambient Operating
25
50
50
V
DD
75
= 3.0V
V
C
75
DD
L
– pF
C
= 3.0V
100
L
– pF
100
125
ADSP-216x
125
150
150
175
175