The VIN pin must be buffered to ground with a low-ESR ceramic bypass-capacitor. The recommended capacitor value can range from 1 μF to 10 μF. The capacitor must have a voltage rating of 10 V minimum and a X5R or X7R dielectric.
The optimum placement is closest to the VIN and GND pins at the board entrance to minimize the loop area formed by the bypass-capacitor connection, the VIN terminal, and the GND pin. See Figure 9-10 for a PCB layout example.
The connections between the device SW1 and SW2
pins and the transformer primary endings, and the connection of the device
VCC pin and the transformer center-tap must be as close as
possible for minimum trace inductance.
The connection of the device VCC pin and the transformer center-tap must be buffered to ground with a low-ESR ceramic bypass-capacitor. The recommended capacitor value can range from 1μF to 10 μF. The capacitor must have a voltage rating of 16 V minimum and a X5R or X7R dielectric.
The device GND pins must be tied to the PCB ground plane using two vias for minimum inductance.
The ground connections of the capacitors and the ground plane should use two vias for minimum inductance.
The rectifier diodes should be Schottky diodes
with low forward voltage and low capacitance to maximize efficiency.
The VOUT pin must be buffered to
ISO-Ground with a low-ESR ceramic bypass-capacitor. The recommended capacitor
value can range from 1μF to 10 μF.