LV5028TT

No.A1999-11/16

Bleeder current cuircuit for TRIAC dimmer

1. Operating voltage setting

ACS pin voltage set operating voltage at OUT2. ACS pin threshold volage is 3V typ.

OUT2 operating voltage is set by R1 and R2. R1 and R2 is determined below.

ACS = Vac

×

R2

R1+R2

2. Bleeder current setting

Rd set hold current at Triac dimmer.

Bleeder current is set at Rd depending on Triac dimmer.

a blockdiagram in outline

a blockdiagram in outline

ACS

VACS

(3V typ)

+

-

OUT2

Rd

R2

R1

VAC voltage is Low,

OUT2 is High voltage

Triac dimmer, OFF

Bleeder circuit, ON (OUT2; high)

VACS (3V typ)

min

on

min

on

on

on

on

on

on

off

off

off

Vac

ACS

OUT2

OUT