N - Channel Buck Switch and

An external re-circulating diode from the SW pin to ground is

necessary to carry the inductor current after the internal

Buck switch turns off. This external diode must be of the

Ultra-fast or Schottky type to reduce turn-on losses and

current over-shoot. The reverse voltage rating of the re-

circulating diode must be greater than the maximum line

input voltage.

Thermal Protection

Internal Thermal Shutdown circuitry is provided to protect the

integrated circuit in the event the maximum junction tem-

perature is exceeded. When thermal protection is activated,

typically at 165 degrees Celsius, the controller is forced into

a low power reset state, disabling the output driver. This

feature is provided to prevent catastrophic failures from ac-

cidental device overheating.

10V, 400mA Demo Board Bill of Materials (See Typical Application Circuit)

ITEM

PART NUMBER

DESCRIPTION

VALUE

C1

C4532X7R2A105M

CAPACITOR, CER, TDK

1µ, 100V

C2

C4532X7R1E156M

CAPACITOR, CER, TDK

15µ, 25V

C3

C1206C104K5RAC

CAPACITOR, CER, KEMET

0.1µ, 50V

C4

C1206C103K5RAC

CAPACITOR, CER, KEMET

0.01µ, 50V

C5

C3216X7R2A104KT

CAPACITOR, CER, TDK

0.1µ, 100V

D1

MURA110T3

DIODE, 100V, ON SEMI

L1

SLF7045T-101MR60-1

BUCK INDUCTOR, TDK

100µH

R1

CRCW12062003F

RESISTOR

200K

R2

CRCW12061003F

RESISTOR

100K

R3

CRCW12063011F

RESISTOR

3.01K

R4

CRCW12061001F

RESISTOR

1K

R5

CRCW12061R00F

RESISTOR

1

U1

LM25007

REGULATOR, NATIONAL

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