BD9207FPS
Resistance R1
LED Current value is set below according to sense resistance R1.
ILED[A]=VINV[V]/R1[Ω]
=0.2V/R1[Ω]
Moreover, DCDC Output voltage will be the value below.
VO[V]=VF(LED Forward voltage)+VINV[V]
=VF+0.2V(typ)
● Recommended circuit example and notes of substrate layout
Technical Note
・ To prevent noise and low efficiency, please set up the capacitor and Schottky diode between VCC – GND as near as
possible to IC.
・ Please connect the resistance and output LC filter capacitor between INV – GND with same GND for the stability of
output voltage.
<Recommended parts example>
Coil
L1=10μH
Diode
Capacitor
Resistance
D1
C1=10μF(25V)
C2=4.7μF(50V)
R1=0.43Ω
:C6-K3LA(mitsumi)
:RB050LA-30(ROHM)
:Ceramic capacitor GRM31CB31E106KA75L(murata)
:Ceramic capacitor GRM32EB31H475KA87L(murata)
:MCR10EZPFR430(ROHM)
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6/11
2009.07 - Rev.A