SMJL-3P22W4P3 Datasheet, PDF (10/28 Pages) Seoul Semiconductor – Integrated AC LED Solution

Analog Dimming Mode
Product Data Sheet
SMJL-3P22W4P3 – Acrich3 22W
■ Operation
The LED brightness can be adjusted by applying DC voltage to ADIM pin. When
0.40V< ADIM pin voltage <2.0V, Acrich3.0 operates in positive polarity mode as shown below
figure. When the ADIM DC voltage becomes over 2.0V, the LED brightness is clamped at
their maximum flux. When ADIM DC voltage is decreased to 0.40V, LED current becomes off.
LED Current
100%
Analog Dimming
Region
Output Clamping
Region
0%
0.4V
2.0V
ADIM Pin
DC Input Voltage
■ External Resistor Setting – For Example
The V_ADIM voltage is set using a resistive voltage divider from the V_{DIM_IN} to ADIM pin. The
recommended R_ADIM1 resistor at 10kΩ. Calculate the R_ADIM2 resistor using the following
equation.
R_ADIM1 x V_ADIM
R_ADIM2 =
V_{DIM_IN} - V_ADIM
Assumptions for the purposes of this example, the following are given as the application
requirements:
- V_{DIM_IN}
- R_ADIM1
- V_ADIM
: External dimming voltage signals (0V : Min, 10V : Max)
: 10kΩ (Recommended value^[1])
: 2V (Constant value^[2])
R_ADIM2 =
R_ADIM1 x V_ADIM
V_{DIM_IN} - V_ADIM
10KΩ x 2V
=
10V - 2V
= 2.5KΩ
Notes :
[1] Considering the power consumption of the IC, set the resistance value.
[2] When the Acrich3.0 V_ADIM Pin level is 2V, the LED Flux reaches the 100%.
Rev1.1, Sep 10, 2015
10
www.seoulsemicon.com