IDT82V3280 Integrated Device Technology, IDT82V3280 Datasheet - Page 149

• Manufacturer Part Number: IDT82V3280
• Description: Wan Pll
• Manufacturer: Integrated Device Technology

Table 43: Power Consumption and Maximum Junction Temperature
8
+85°C. To ensure the functionality and reliability of the device, the maxi-
mum junction temperature T
applications, the device will consume more power and a thermal solution
should be provided to ensure the junction temperature T
exceed the T
8.1
geographical center of the chip where the device's electrical circuits are.
It can be calculated as follows:
be used. The θ
in the loads.
ments.
8.2
Table 44: Thermal Data
Thermal Management
IDT82V3280
TQFP/PN100
TQFP/DQ100
The device operates over the industry temperature range -40°C ~
Junction temperature T
Where:
In order to calculate junction temperature, an appropriate θ
Power consumption is the core power excluding the power dissipated
Package
Assume:
TQFP/DQ100
TQPF/DQ100
TQFP/PN100
Package
Equation 1: T
θ
T
T
P = Device Power Consumption
T
θ
P = 1.9W
A
A
JA
j
JA
= Junction Temperature
= 85°C
= Ambient Temperature
= 18.5°C/W (TQFP/DQ100 Soldered & when airfow rate is 0 m/s)
= Junction-to-Ambient Thermal Resistance of the Package
THERMAL MANAGEMENT
JUNCTION TEMPERATURE
EXAMPLE OF JUNCTION TEMPERATURE
CALCULATION
jmax
Table 43
JA
Consumption (W)
.
is shown in
Pin Count Thermal Pad
j
Power
= T
1.9
1.9
100
100
100
provides power consumption in special environ-
A
+ P X
j
is the temperature of package typically at the
jmax
Table
θ
Yes/Soldered
Yes/Exposed
JA
should not exceed 125°C. In some
Operating
44:
Voltage
No
(V)
3.6
3.6
T
A
θ
85
85
(°C)
JC
11.0
10.8
10.8
(°C/W)
Temperature (°C)
Maximum
Junction
j
125
125
does not
JA
θ
JB
must
34.2
23.7
3.0
(°C/W)
149
temperature of 125°C so no extra heat enhancement is required.
might exceed the maximum junction temperature of 125°C and an exter-
nal thermal solution such as a heatsink is required.
8.3
attached. θ
resistance, as the heat flowing from the die junction to ambient goes
through the package and the heatsink. θ
tion temperature does not exceed the maximum junction temperature.
According to Equation 1 and 2, the heatsink-to-ambient thermal resis-
tance θ
as follows:
θ
ment, the junction temperature will not exceed the maximum junction
temperature.
HA
The junction temperature T
The junction temperature of 120.2°C is below the maximum junction
In some operation environments, the calculated junction temperature
A heatsink is expanding the surface area of the device to which it is
Where:
θ
Assume:
The heatsink-to-ambient thermal resistance θ
That is, if a heatsink whose heatsink-to-ambient thermal resistance
HA
is below or equal to 10.3°C/W is used in such operation environ-
27.2
18.5
39.3
0
T
Equation 2:
θ
θ
HA
Equation 3:
T
T
P = 1.9W
θ
θ
determines which heatsink can be selected to ensure the junc-
A
j
JC
HA
j
JC
HA
= T
= 125°C (T
= 85°C
can be calculated as follows:
JA
= Junction-to-Case (Heatsink) Thermal Resistance
= 10.8°C/W (TQFP/DQ100)
= Heatsink-to-Ambient Thermal Resistance
= (125°C - 85°C ) / 1.9W - 10.8°C/W = 10.3°C/W
HEATSINK EVALUATION
A
is now a combination of device case and heat-sink thermal
+ P X
36.2
24.7
15.4
1
θ
θ
jmax
θ
JA
HA
JA
=
= (T
)
= 85°C + 1.9W X 18.5°C/W = 120.2°C
θ
θ
JA
JC
j
- T
(°C/W) Air Flow in m/s
34.3
23.3
13.9
+
A
j
2
θ
can be calculated as follows:
) / P -
HA
θ
JC
JA
33.5
22.4
13.1
3
can be calculated as follows:
HA
32.9
21.9
12.6
can be calculated
4
June 19, 2006
WAN PLL
32.6
21.5
12.2
5