4180G Aavid Thermalloy, 4180G Datasheet - Page 10

• Manufacturer Part Number: 4180G
• Description: ALUMINUM OXIDE INSULATOR
• Manufacturer: Aavid Thermalloy
• Type: Transistor Insulatorr

Specifications of 4180G

• Features: High Frequency Usage
• Shape: Rectangular
• Length: 0.915" (23.24mm)
• Width: 0.740" (18.80mm)
• Height: 0.080" (2.03mm)
• For Use With/related Products: TO-218, TO-247 and TO-3P
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Color: -
• Diameter - Inside: -
• Diameter - Outside: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 34004

10
Find a space saving heat sink to keep a TO-220 device below the
maximum 150°C junction temperature in natural convection. Device
will be screw mounted with an electrically conductive interface.
Given:
P D = 6 watts
R θJC = 3°C/W (from semiconductor manufacturer)
T J max = 150°C (from semiconductor manufacturer)
T A max = 65°C
A Kondux
applications. Thermal resistance for Kondux
from the following graph.
At 2 in-lb of torque the thermal resistance
is approximately R θCS = 0.5°C/W
Using equation 1, solve for R θSA
R θSA = 150 – 65 - ( 3 + 0.5) = 10.7°C/W
The Index by Heat Sink Style on page 8 lists space saving heat sinks.
Several models are in the 10 °C/W range. Choose the one that best
fits the application and verify thermal resistance from graph.
Part number 593202B03500G shows
a 60 °C temperature rise at 6 watts.
R θSA = 60 = 10.0°C/W
Which meets the above requirement in natural convection.
Example A
How To Select a Heat Sink
www.aavidthermalloy.com
100
6
80
60
40
20
TM
0
0
6
0
pad is a good choice for electrically conductive
0.60
0.50
0.40
0.30
0.20
0.10
0.00
200
2
0
Air Velocity—Feet Per Minute
Heat Dissipated—Watts
1
400
4
Typical TO-220 Performance
2
Screw Torque (in-lb)
600
6
AMERICA
EUROPE
3
800
8
4
1000
10
10
5
Italy Tel: [phone] email: [e-mail]
United Kingdom Tel: [phone] email: [e-mail]
8
6
4
2
0
USA Tel: [phone] email: [e-mail]
TM
6
can be determined
Example B
Find a heat sink to keep a TO-220 device below the maximum
150 °C junction temperature in forced convection at 400 ft/min.
Device must be electrically insulated and mounted with a labor
saving clip.
Given:
P D = 12 watts
R θJC = 2.5°C/W (from semiconductor manufacturer)
T J max = 140°C (from semiconductor manufacturer)
T A max = 50°C
A Hi-Flow® pad works great with clip mounting and provides the
necessary electrical insulation. Thermal resistance for
Hi-Flow® at low pressure is 1.15°C/W (from page 87).
Using equation 1, solve for R θSA
R θSA = 140 – 50 - (2.5 + 1.15) = 3.85°C/W
Many styles are available. If board space is a concern,
533202B02551G (pg 55) meets the requirements.
According to the above graph, an airflow of 400 ft/min results
in a thermal resistance of 3°C/W. This is less than the required
thermal resistance of 3.85°C/W and is therefore acceptable
under these airflow conditions.
If height is a concern, 533702B02552G would meet the
requirements and is only 1.0” tall
Hi-Flow® is a trademark of the Bergquist Company
53320X
53330X
12
100
80
60
40
20
0
ASIA
0
0
200
2
Singapore Tel: [phone] email: [e-mail]
Taiwan Tel: [phone] email: [e-mail]
Air Velocity—Feet Per Minute
Heat Dissipated—Watts
400
4
600
6
800
8
1000
10
10
0
8
6
4
2