TSL235R
LIGHT-TO-FREQUENCY CONVERTER
TAOS038E
−SEPTEMBER
2007
TYPICAL CHARACTERISTICS
OUTPUT FREQUENCY
vs
IRRADIANCE
1000
V
DD
= 5 V
λ
p
= 635 nm
T
A
= 25°C
Normalized Responsivity
1.2
PHOTODIODE SPECTRAL RESPONSIVITY
f
O
— Output Frequency — kHz
100
1.0
10
0.8
1
0.6
0.1
0.4
0.01
0.2
0.001
0.001
0.01
0.1
1
10
10 0
1k
0
300
400
500
E
e
−
Irradiance
−
μW/cm
2
600 700 800 900
λ
−
Wavelength
−
nm
1000 1100
Figure 1
DARK FREQUENCY
vs
TEMPERATURE
1.2
V
DD
= 5 V
E
e
= 0
Figure 2
TEMPERATURE COEFFICIENT
OF OUTPUT FREQUENCY
vs
WAVELENGTH OF INCIDENT LIGHT
7000
6000
5000
4000
3000
2000
1000
0
300
V
DD
= 5 V
1
f
O(dark)
— Dark Frequency — Hz
0.8
0.6
0.4
0.2
0
−25
0
25
50
T
A
−
Temperature
−
°C
75
Temperature Coefficient of Output Frequency — ppm/5C
400
500
600
700
800
900
1000
λ
−
Wavelength of Incident Light
−
nm
Figure 3
Figure 4
The
LUMENOLOGY
r
Company
r
r
Copyright
E
2007, TAOS Inc.
www.taosinc.com
3
TAOS [ TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS ]
