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SC411

POWER MANAGEMENT

The layout can be considered in two parts, the control section referenced to VSSA and the power section. Looking at

the control section first, locate all components referenced to VSSA on the schematic and place these components at

the chip. Drop vias to the ground plane as needed.

Figure 5: Components Connected to VSSA

Figure 6: Control Section Example

In Figure 6 above, all components referenced to VSSA have been placed and connected to the ground plane with

with vias. Note how the VSSA and PGND pins are connected directly to the thermal pad, which has 4 vias to the

ground plane (not shown).

VOUT

VBAT

C8

1nF

R1

1M

C10

1uF

5VSUS

R2

10R

5VSUS

VOUT

1

VCCA

2

FB

3

PGD

4

VDDP

9

ILIM

10

LX

11

DH

12

U1

SC411

C5

56p

0402

0402

0402

0402

0402

0402

0603

0603

C9

1uF

R3

20k0

R5

14k3