CM3106-12SB CALMIRCO [California Micro Devices Corp], CM3106-12SB Datasheet - Page 9

• Manufacturer Part Number: CM3106-12SB
• Description: 2 Amp Source/ Sink Bus Termination Regulator
• Manufacturer: CALMIRCO [California Micro Devices Corp]

02/02/04
Application Information
PCB Layout Considerations
The CM3106-12SB has a heat spreader attached to
the underneath of the PSOP-8 package in order for
heat to be transferred much easier from the package to
the PCB. The heat spreader is a copper pad of dimen-
sions just smaller than the package itself. By position-
ing the matching pad on the PCB top layer to connect
to the spreader during manufacturing, the heat will be
transferred between the two pads. The drawing below
shows the recommended PCB layout. Note that there
are six vias on either side to allow the heat to dissipate
into the ground and power planes on the inner layers of
© 2004 California Micro Devices Corp. All rights reserved.
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
V
PV
AV
DDQ
IN
IN
C
AVIN
47µF
Figure 16. Recommended Heat Sink PCB Layout
Figure 15. Typical Application Circuit
47µF
C
PVIN
AV
PV
V
DDQ
IN
IN
L Tel: [phone] L Fax: [phone] L www.calmicro.com
CM3106
GND
the PCB. Vias can be placed underneath the chip, but
this can cause blockage of the solder. The ground and
power planes should be at least 2 sq in. of copper by
the vias. It also helps dissipation to spread if the chip is
positioned away from the edge of the PCB, and not
near other heat dissipating devices. A good thermal
link from the PCB pad to the rest of the PCB will ensure
a thermal link from the CM3106 package to ambient,
θ
JA
V
, of around 40°C/W.
SENSE
V
V
REF
TT
C
REF
0.1µF
C
220µF
TT
V
V
REF
TT
CM3106
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