Datasheet

High
Frequency
Current
Path
L1
R1
C3
C1
C2
PGND
SW
V
BAT
BAT
V
IN
CurrentDirection
ToSRP -SRNpin
R
SNS
CurrentSensingDirection
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www.ti.com SLUS893A –MARCH 2010– REVISED OCTOBER 2011
charger power ground to the charger analog ground. Just beneath the IC, use the copper pour for analog
ground, but avoid power pins to reduce inductive and capacitive noise coupling. Connect analog ground to
GND. Connect the analog ground and power ground together using the thermal pad as the single ground
connection point. Or using a 0-Ω resistor to tie analog ground to power ground (the thermal pad should tie to
analog ground in this case). A star-connection under the thermal pad is highly recommended.
8. It is critical that the exposed thermal pad on the back side of the IC package be soldered to the PCB ground.
Ensure that there are sufficient thermal vias directly under the IC, connecting to the ground plane on the
other layers.
9. Decoupling capacitors should be placed next to the IC pins to make trace connections as short as possible.
10. All via sizes and numbers should be enough for a given current path.
Figure 18. High Frequency Current Path
Figure 19. Sensing Resistor PCB Layout
See the EVM design (SLUU410) for the recommended component placement with trace and via locations.
For QFN information, see SCBA017 and SLUA271.
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