12

09/2008 Rev 1.2

,

Power Analog Microelectronics Inc

www.poweranalog.com

PAM2305

1A Step-Down DC-DC Converters

PCB Layout Check List

When laying out the printed circuit board, the following checklist should be used to ensure proper operation of

the PAM2305. These items are also illustrated graphically in Figure 1. Check the following in your layout:

1.

The power traces, consisting of the GND trace, the SW trace and the VIN trace should be kept short, direct

and wide.

2.

Does the V

pin connect directly to the feedback resistors? The resistive divider R1/R2 must be con nected

between the (+) plate of C

and ground.

3.

Does the (+) plate of CIN connect to VIN as closely as possible? This capacitor provides the AC current to

the internal power MOSFETs.

4.

Keep the switching node, SW, away from the sensitive VFB node.

5.

Keep the (–) plates of C and C

as close as possible.

FB

OUT

IN

OUT

Figure 1 :PAM2305 Suggested Layout