STK740-441

No.6106–4/10

Test Circuit

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2

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12

DC

INPUT

GND

OUTPUT

(3.3V)

ON/OFF

Vo adjust

L1

GND

C1

C2

FB

C1

: 220

µF/10V (OS capacitor)

C2

: 2200

µF/6.3V

L1

: 30

µH

FB

: Ferrite-bead core

Overvoltage Protection Circuit

In a constant-voltage power supply circuit output voltage may generally exceed the stipulated rating (equivalent to input

voltage) when the circuit is broken down or the IC and the printed circuit board is wrongly soldered. Therefore overvoltage

protection circuit is recommended to use to minimize the damages caused by the overvoltage.

Sample the overvoltage protection circuit

DC

INPUT

GND

OUTPUT

GND

Regulator

FUSE

SCR

CR