AP65403

Document number: DS37126 Rev. 1 - 2

12 of 15

www.diodes.com

March 2014

© Diodes Incorporated

AP65403

PC Board Layout

This is a high switching frequency converter. Hence attention must be paid to the switching currents interference in the layout. Switching current

from one power device to another can generate voltage transients across the impedances of the interconnecting bond wires and circuit traces.

These interconnecting impedances should be minimized by using wide, short printed circuit traces.

Note that the IN to GND decoupling

capacitors need to be immediately adjacent to the IN and GND pins of the device (U1), and 12 thermal vias from the back side thermal pad to

the GND plane are essential to achieve the best operation at full load current.

Figure 4. PC Board Layout

External Bootstrap Diode

It is recommended that an external bootstrap diode be added when the input voltage is no greater than 5V or the 5V rail is available in the

system. This helps to improve the efficiency of the regulator. This solution is also applicable for D > 65%. The bootstrap diode can be a low cost

Figure 5—External Bootstrap Compensation Components

Recommended Diodes:

Part Number

Voltage/Current

Rating

Vendor

B130

30V, 1A

Diodes Inc

SK13

30V, 1A

Diodes Inc