Datasheet

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PowerPAD PACKAGE
Assembly Process
ADS5500
SBAS303F – DECEMBER 2003 – REVISED FEBRUARY 2007
Write D000h (Address D, Data 000) Data section. The recommended thermal pad
Write E000h (Address E, Data 804) dimension is 8 mm x 8 mm.
Write 0000h (Address 0, Data 000)
2. Place a 5-by-5 array of thermal vias in the
Write 1000h (Address 1, Data 000)
thermal pad area. These holes should be 13
Write F000h (Address F, Data 000).
mils in diameter. The small size prevents
wicking of the solder through the holes.
NOTE: This procedure is only required if a RESET
pulse is not provided to the device. 3. It is recommended to place a small number of
25 mil diameter holes under the package, but
outside the thermal pad area to provide an
additional heat path.
The PowerPAD package is a thermally enhanced
4. Connect all holes (both those inside and
standard size IC package designed to eliminate the
outside the thermal pad area) to an internal
use of bulky heat sinks and slugs traditionally used in
copper plane (such as a ground plane).
thermal packages. This package can be easily
5. Do not use the typical web or spoke via
mounted using standard printed circuit board (PCB)
connection pattern when connecting the
assembly techniques and can be removed and
thermal vias to the ground plane. The spoke
replaced using standard repair procedures. AVDD.
pattern increases the thermal resistance to the
The programming is done through a three-wire
ground plane.
interface. The timing diagram and serial register
setting in the Serial Programing Interface section
6. The top-side solder mask should leave
describe the programming of this register.
exposed the terminals of the package and the
thermal pad area.
The PowerPAD package is designed so that the lead
7. Cover the entire bottom side of the PowerPAD
frame die pad (or thermal pad) is exposed on the
vias to prevent solder wicking.
bottom of the IC. This provides a low thermal
resistance path between the die and the exterior of
8. Apply solder paste to the exposed thermal
the package. The thermal pad on the bottom of the
pad area and all of the package terminals.
IC can then be soldered directly to the printed circuit
For more detailed information regarding the
board (PCB), using the PCB as a heatsink.
PowerPAD package and its thermal properties, see
Programming is done through a three-wire interface.
either the SLMA004 B application brief PowerPAD
The timing diagram and serial register setting in the
Made Easy or SLMA002 technical brief PowerPAD
Serial Programing Interface section describe the
Thermally Enhanced Package.
programming of this register.
1. Prepare the PCB top-side etch pattern
including etch for the leads as well as the
thermal pad as illustrated in the Mechanical
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