PVDD and VDD pins must be
bypassed to ground using low-ESR ceramic capacitors with recommended values.
These capacitors should be placed as close to the pins as possible with a thick
trace or ground plane connection to the device GND pin.
Additional bulk capacitance may
be required to on PVDD pin. This bulk capacitance should be placed such that it
minimizes the length of any high current paths. The connecting metal traces
should be as wide as possible, with numerous vias connecting PCB layers. These
practices minimize inductance and allow the bulk capacitor to deliver high
current.
All PVDD, OUTx and GND pins must
be shorted externally with sufficiently wide traces.
The following figure shows a
layout example for a 4cm X 4cm x 1.6mm, 4-layer PCB for the leaded HTSSOP
package device. The 4 layers uses 2oz copper on top/ bottom signal layers and
1oz copper on internal supply layers, with 0.3mm thermal via drill diameter,
0.025mm Cu plating, 1mm minimum via pitch.