CAT6243_16 Datasheet, PDF (12/15 Pages) ON Semiconductor – 1 Amp Adjustable CMOS LDO Voltage Regulator

CAT6243
300
250
1 oz C.F
2 oz C.F
200
1 oz Sim
2 oz Sim
150
100
50
0
0 25 50 75 100 125 150 175 200 225 250 275 300
650
Copper heat spreading area (mm²)
Figure 28. Thermal Resistance vs. PCB Copper Area for 3 mm x 3 mm WDFN Package
PCB Layout Top Layer and
connections to heat spreading plane
Close−up of pad area
Figure 29. Topside Copper Foil Pattern for Heat Dissipation
Design Hints
V_IN and GND printed circuit board traces should be as
wide as possible. When the impedance of these traces is high
due to narrow trace width or long length, there is a chance
to pick up noise or cause the regulator to malfunction. Place
external components, especially the input and output
capacitors, as close as possible to the CAT6243, and keep
traces between power source and load as short as possible.
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