LAYOUT HINTS

These are several guidelines to follow while designing the

PCB layout for an LM2852 application.

1.

The input bulk capacitor, C

close to the PVIN pin to keep the resistance as low as

possible between the capacitor and the pin. High current

levels will be present in this connection.

2.

All ground connections must be tied together. Use a

broad ground plane, for example a completely filled back

plane, to establish the lowest resistance possible be-

tween all ground connections.

3.

The sense pin connection should be made as close to

the load as possible so that the voltage at the load is the

expected regulated value. The sense line should not run

too close to nodes with high EMI (such as the switch

node) to minimize interference.

4.

The switch node connections should be low resistance

to reduce power losses. Low resistance means the trace

between the switch pin and the inductor should be wide.

However, the area of the switch node should not be too

large since EMI increases with greater area. So connect

the inductor to the switch pin with a short, but wide trace.

Other high current connections in the application such

as PVIN and V

low resistance and EMI.

5.

Allow area under the chip to solder the entire exposed

die attach pad to ground for improved thermal and elec-

trical performance.

LM2852 Example Circuit Schematic

Bill of Materials for 500kHz (LM2852Y) 3.3V

ID

Part Number

Type

Size

Parameters

Qty

Vendor

U

1

LM2852YMXA-1.8

2A Buck

ETSSOP-14

1

NSC

L

O

DO3316P-153

Inductor

15 µH

1

Coilcraft

C

595D107X_6R3C2T

Capacitor

Case Code “C”

1

Vishay-Sprague

C

IN

GRM32ER60J476ME20B

Capacitor

1210

47µF/X5R/6.3V

1

Murata

C

INX

GRM21BR71C105KA01B

Capacitor

0805

1µF/X7R/16V

1

Murata

C

SS

VJ0805Y272KXXA

Capacitor

0805

1

Vishay-Vitramon

R

f

CRCW060310R0F

Resistor

0603

10

1

Vishay-Dale

C

f

GRM21BR71C105KA01B

Capacitor

0805

1µF/X7R/16V

1

Murata

Bill of Materials for 1500kHz (LM2852X) 3.3V to 1.8V Conversion

ID

Part Number

Type

Size

Parameters

Qty

Vendor

U

1

LM2852XMXA-1.8

2A Buck

ETSSOP-14

1

NSC

L

0

DO1813P-102HC

Inductor

1 µH

1

Coilcraft

C

0

GRM32DR61E106K

Capacitor

1210

10 µF/X5R/25V

1

Murata

C

IN

GRM32ER60J476ME20B

Capacitor

1210

47µF/X5R/6.3V

1

Murata

C

INX

GRM21BR71C105KA01B

Capacitor

0805

1µF/X7R/16V

1

Murata

C

SS

VJ0805Y272KXXA

Capacitor

0805

1

Vishay-Vitramon

R

f

CRCW060310R0F

Resistor

0603

10

1

Vishay-Dale

C

f

GRM21BR71C105KA01B

Capacitor

0805

1µF/X7R/16V

1

Murata

20127020

FIGURE 1.

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