Typical application 2, Rv5vh3 – Ricoh RV5VH User Manual

Page 46

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RV5VH3

××

42

CSW

FB1

V

DD

EXT1

D

OUT

FB2

EXT2

GND

C2

L2

PMOS

R3

R1

V

IN

R2

C3

SBD

C1

NPN Tr.

SBD

R6

R4

C4

R5

C5

L1

Output DC/DC 2

Output DC/DC 1

TYPICAL APPLICATION 2

CoiI

L1 : 100µH, L2 : 100µH

Diode

Schottky type

capacitor

C1 : 22µF(Ta), C2 : 22µF(Ta)
C3 : 0.01µF (ceramic)
C4 : 0.01µF (ceramic)
C5 : 0.01µF (ceramic)

PMOS

2SJ238 (TOSHIBA)

NPN Tr.

2SD1628G (SANYO)

Resistor

R1 : 100K

, R2 : 0 to 500K

R3 : 100K

R4 : 300

R5 : 0 to 500K

Ω,

R6 : 50K

Description

• Step up DC/DC converter : DC/DC1

The oscillator can operate when CSW is “H”. When the CSW is “L” the EXT1 outputs GND.

The output voltage can be adjusted by R5 and R6 with FB1 of two volt.

• Invering DC/DC converter : DC/DC2

The oscillator can operate when CSW is “H”. When the CSW is “L” the EXT2 outputs V

DD

.

The output voltage can be adjusted by R1 and R2 with FB2 of zero volt.

• VoItage Detector

V

DD

pin can be monitored. This could be operated all the time by V

DD

.

The D

OUT

pin outputs “L” when low voltage is detected with Nch open-drain output.

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