LT1739CUE Linear Technology, LT1739CUE Datasheet - Page 11

• Manufacturer Part Number: LT1739CUE
• Description: IC AMP XDSL LINE DVR DUAL 12-DFN
• Manufacturer: Linear Technology
• Type: Line Driver, Transmitterr

Specifications of LT1739CUE

• Number Of Drivers/receivers: 2/0
• Voltage - Supply: 5 V ~ 12 V
• Mounting Type: Surface Mount
• Package / Case: 12-DFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Protocol: -

APPLICATIO S I FOR ATIO
When PCB cards containing multiple ports are inserted
into a rack in an enclosed cabinet, it is often necessary to
provide airflow through the cabinet and over the cards. As
Figure 8. Examples of PCB Metal Used for Heat Dissipation. Driver Package Mounted on Top Layer.
Heat Sink Pad Soldered to Top Layer Metal. Metal Areas Drawn to Scale of Package Size
U
STILL AIR
100 C/W
130 C/W
50 C/W
45 C/W
75 C/W
TSSOP
TSSOP
TSSOP
DFN
DFN
U
JA
PACKAGE
W
–20
–30
–40
–50
–60
–10
0
0
Laminar Airflow Over the Device
AIRFLOW (LINEAR FEET PER MINUTE, lfpm)
TOP LAYER
Typical Reduction in
100
U
200
300
400
% REDUCTION RELATIVE
TO
500
2ND LAYER
JA
600
seen in the graph of Figure 8, this is also very effective in
further reducing the junction-to-ambient thermal resis-
tance of each line driver.
IN STILL AIR
700
JA
800
with
900
1739 F08b
1000
3RD LAYER
BOTTOM LAYER
1739 F08a
LT1739
1739fas, sn1739
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