ZXLD1321EV2
Issue 2 – April 2008
www.zetex.com
© Zetex Semiconductors plc, 2008
5
Layout considerations
PCB tracks should be kept as short as possible to minimize ground bounce, and the ground pin of the device
should be soldered directly to the ground plane. It is particularly important to mount the coil and the input/output
capacitors close to the device to minimize parasitic resistance and inductance, which will degrade efficiency. The
VIN pin is prone to noise. Input decoupling capacitor C2 should be kept as close as possible between the VIN
and GND pin. Enough copper should be attached to the GND pin (exposed pad) for heat-sinking purposes. In this
EV board, the copper area is at the bottom layer, connected to the exposed pad through a few plated through
holes.
Below is the recommended layout of the ZXLD1321EV2.
Top Silk
Top Copper
Bottom Copper
Drill File