Applications Information (Cont.)

GND

VIN

LXA

LXB

GND

SC198

CinA

CinB

VOUTA

VOUTB

CinR

Note:

Control pin routings are not shown.

PCB Layout Considerations

Poor layout can degrade the performance of the DC-DC converter and can be a contributory factor in EMI problems,

ground bounce, thermal issues, and resistive voltage losses. Poor regulation and instability can result.

The following design rules are recommended:

Place the inductor and filter capacitors as close to the device as possible and use short wide traces between the

power components.

Route the output voltage feedback path away from inductor and LX node to minimize noise and magnetic

interference.

Use a ground plane to further reduce noise interference on sensitive circuit nodes.

1.

2.

3.

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© 2006 Semtech Corp.

www.semtech.com

SC198

POWER MANAGEMENT