ISL9105 Datasheet, PDF (10/11 Pages) Intersil Corporation – 600mA Low Quiescent Current 1.6MHz High Efficiency Synchronous Buck Regulator

ISL9105
PCB Layout Recommendation
The PCB layout is a very important converter design step to
make sure the designed converter works well.
For ISL9105, the power loop is composed of the output
inductor L, the output capacitor C_OUT, the PHASE pin and
the GND pin. It is necessary to make the power loop as
small as possible and the connecting traces among them
should be direct, short and wide.
The switching node of the converter, the PHASE pin, and the
traces connected to the node are very noisy, so keep the
voltage feedback trace away from these noisy traces.
The input capacitor should be placed to VIN pin as close as
possible. And the ground of input and output capacitors
should be connected as close as possible.
The heat of the IC is mainly dissipated through the thermal
pad. Maximizing the copper area connected to the thermal
pad is preferable. In addition, a solid ground plane is helpful
for better EMI performance.
10
FN6415.2
March 28, 2008