Datasheet

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AGND
BOOT
VSENSE
COMP
PWRGD
PH
PH
PH
PH
PH
RT
SYNC
SS/ENA
VBIAS
VIN
VIN
VIN
PGND
PGND
PGND
VOUT
PH
Vin
TOPSIDE GROUND AREA
VIA to Ground Plane
ANALOG GROUND TRACE
EXPOSED
POWERPAD
AREA
COMPENSATION
NETWORK
OUTPUT INDUCTOR
OUTPUT
FILTER
CAPACITOR
BOOT
CAPACITOR
INPUT
BYPASS
CAPACITOR
INPUT
BULK
FILTER
FREQUENCY SET RESISTOR
SLOW START
CAPACITOR
BIAS CAPACITOR
LAYOUT CONSIDERATIONS FOR THERMAL
Minimum Recommended Exposed
Copper Area For Powerpad. 5mm
Stencils may Require 10 Percent
Larger Area
0.2454
0.0150
0.06
0.0256
0.1700
0.1340
0.0620
0.0400
0.0400
0.0400
0.0600
0.0227
0.0600
0.1010
6 PL ∅ 0.0130
4 PL ∅ 0.0180
Connect Pin 1 to Analog Ground Plane
in This Area for Optimum Performance
Minimum Recommended Top
Side Analog Ground Area
Minimum Recommended Thermal Vias: 6 × .013 dia.
Inside Powerpad Area 4 × .018 dia. Under Device as Shown.
Additional .018 dia. Vias May be Used if Top Side Analog
Ground Area is Extended.
0.2560
TPS54310
SLVS412D – DECEMBER 2001 – REVISED FEBRUARY 2007
Figure 11. TPS54310 PCB Layout
area of the PowerPAD to the analog ground plane
layer should be made using 0.013 inch diameter vias
to avoid solder wicking through the vias. Six vias
PERFORMANCE
should be in the PowerPAD area with four additional
For operation at full rated load current, the analog
vias located under the device package. The size of
ground plane must provide adequate heat dissipating
the vias under the package, but not in the exposed
area. A 3 inch by 3 inch plane of 1 ounce copper is
thermal pad area, can be increased to 0.018.
recommended, though not mandatory, depending on
Additional vias beyond the ten recommended that
ambient temperature and airflow. Most applications
enhance thermal performance should be included in
have larger areas of internal ground plane available,
areas not under the device package.
and the PowerPAD should be connected to the
largest area available. Additional areas on the top or
bottom layers also help dissipate heat, and any area
available should be used when 3 A or greater
operation is desired. Connection from the exposed
Figure 12. Recommended Land Pattern for 20-Pin PWP PowerPAD
10
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