UL23EB

Preliminary

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

5 of 8

www.unisonic.com.tw

QW-R125-071.c



TYPICAL APPLICATION CIRCUIT (Cont.)

The UL23EB is a linear constant current IC that supports the adjust brightness or color temperature in 3 grades.

The output current can be adjusted from 5mA to 60mA, and constant current accuracy up to ± 4%.

In the Adjust Brightness Mode application of UL23EB,User can change the size of the output current by turn on/off

the power switch, that adjust brightness of LED lights. Changing the REXT external resistance Adjustment of

brightness ratio.

Open the switch for the 1st time, during constant current：

REXT1

REXT2

0.6

I1=

RR



Open the switch for the 2nd time, during constant current：

REXT2

0.3

I2=

R

Open the switch for the 3rd time, during constant current：

REXT2

0.6

I3=

R

The dimming ratio is 100%，50%，X%,

REXT2

REXT1

REXT2

R

X%=

R+R

The dimming ratio is 10%, 50%, 100%

When the switching period > 3S, System reset.