Datasheet

Photo Current
I
Ph
[µA]
PD measurement to the LED drive (PWM) signal to know the amount of light coming from the
ambient and ambient plus LED. By signal processing you can easily subtract the environmental
influence from your PD signal to get the pure LED light.
Illuminance E
V
[lx] Photo Current I
Ph
[µA]
500 - 4
Table 4
Photo current of PD @ V R = - 5 V
induced only by ambient light of a
certain illuminance at the ACULED. A
CAL-2000 Mercury Argon
1000 - 8
calibration light source was used
for the illumination.
2000 - 16
8000
7000
6000
5000
4000
3000
2000
1000
0
0
ACULED DYO RGBP
PD @ V
R
= -5V
increasing
temperature
T B = 10 - 80 °C
200 400 600 800 1000
LED Forward Current I
F
[mA]
Figure 22
Dependency of the photo current I Ph
from the color, the LED chips’
current I F and the board
temperature T B on the ACULED
DYO. Though the PD is nearly
independent fromT B , temperature
effects occur due to its influence on
the intensities and wavelengths of
the LEDs.
Red, green and blue curves: single
chips (red, green, blue).
Black curves: all chips (RGB)
together.
I Ph is pictured positive.
LED [color] Current I
F
[mA] per Photo Current I
Ph
[µA]
LED
Red 350 - 1740
Table 5
Photo current of a PD placed in
an RGBP ACULED DYO at T B of
25 °C. These numbers
correspond to figure 22.
Red 700 - 3320
Green 350 - 430
Green 700 - 680
Blue 350 - 580
Blue 700 - 970
All (RGB) 350 - 2900
All (RGB) 700 - 5100
www.excelitas.com Driving the ACULED® VHL™ 20