ADSP-2184 Analog Devices, ADSP-2184 Datasheet - Page 26

• Manufacturer Part Number: ADSP-2184
• Description: DSP Microcomputer
• Manufacturer: Analog Devices

ADSP-2184
OUTPUT DRIVE CURRENTS
Figure 20 shows typical I-V characteristics for the output drivers
of the ADSP-2184. The curves represent the current drive
capability of the output drivers as a function of output voltage.
POWER DISSIPATION
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 application where external data memory is used and no
other outputs are active, power dissipation is calculated 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
graph (Figure 21).
(C
Address, DMS
Data Output, WR 9
RD
CLKOUT
Total power dissipation for this example is PINT + 40 mW.
INT
address pins switching.
50% of the data pins switching.
= internal power dissipation from Power vs. Frequency
V
DD
–20
–40
–60
60
40
20
Total Power Dissipation = P
2
0
0
f) is calculated for each output:
V
V
V
Figure 20. Typical Drive Currents
DD
DD
OL
= 5.0V @ +25 C
= 4.5V @ +85 C
10
# of
Pins
8
1
1
V
DD
V
DD
= 5.5V @ –40 C
SOURCE VOLTAGE – V
= 4.5V @ +85 C
20
10 pF
10 pF
10 pF
10 pF
C V
C
DD
DD
V
30
OH
2
= 5.0 V and t
5
5
5
5
INT
V
2
2
2
2
DD
f
V
V
V
V
V
+ (C V
DD
2
40
V
DD
= 5.5V @ –40 C
= 5.0V @ +25 C
f
40 MHz = 80 mW
20 MHz = 45 mW
20 MHz =
40 MHz = 10 mW
DD
50
CK
2
= 25 ns.
f)
140 mW
60
5 mW
–26–
VALID FOR ALL TEMPERATURE GRADES.
1
2
3
4
POWER REFLECTS DEVICE OPERATING WITH NO OUTPUT LOADS.
I
IDLE REFERS TO ADSP-2184 STATE OF OPERATION DURING EXECUTION OF IDLE
TYPICAL POWER DISSIPATION AT 5.0V V
MEMORY. 50% OF THE INSTRUCTIONS ARE MULTIFUNCTION (TYPES 1, 4, 5, 12, 13, 14)
30% ARE TYPE 2 AND TYPE 6, AND 20% ARE IDLE INSTRUCTIONS.
INSTRUCTION. DEASSERTED PINS ARE DRIVEN TO EITHER V
DD
MEASUREMENT TAKEN WITH ALL INSTRUCTIONS EXECUTING FROM INTERNAL
400
375
350
325
300
275
250
225
200
175
150
95
90
85
80
75
70
65
60
55
50
45
40
75
70
65
60
55
50
45
40
35
30
25
82.28mW
44.73mW
62.1mW
62.1mW
330mW
250mW
180mW
2184 POWER, INTERNAL
Figure 21. Power vs. Frequency
34.7mW
32.8mW
33.33
33.33
33.33
POWER, IDLE n MODES
POWER, IDLE
V
1/t
V
1/t
1/t
V
V
V
V
DD
DD
DD
DD
DD
DD
CYC
CYC
CYC
= 5.5V
= 5.0V
= 5.5V
= 4.5V
= 5.0V
= 4.5V
– MHz
– MHz
– MHz
DD
1, 2, 4
AND T
36.6mW
34.3mW
A
1, 2, 3
= 25 C EXCEPT WHERE SPECIFIED.
40
40
40
2
385mW
300mW
225mW
91.52mW
70.55mW
51.705mW
70.55mW
DD
OR GND.
IDLE
IDLE (16)
IDLE (128)
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