TSL230RD
PROGRAMMABLE LIGHT-TO-FREQUENCY CONVERTER
TAOS054A - NOVEMBER 2003
1
The
LUMENOLOGY
r
Company
r
r
Copyright
E
2003, TAOS Inc.
www.taosinc.com
D
High-Resolution Conversion of Light
Intensity to Frequency With No External
Components
D
Programmable Sensitivity and Full-Scale
Output Frequency
D
Communicates Directly With a Microcontroller
D
High Irradiance Responsivity . . .
790 Hz/(
m
W/cm
2
) Typical at 640 nm
D
Single-Supply Operation . . . 2.7 V to 5.5 V
D
Power-Down Feature . . . 5
m
A Typical
D
Nonlinearity Error Typically 0.2% at 100 kHz
D
Stable 200 ppm/
C Temperature Coefficient
D
Low-Profile Surface-Mount Package
Description
The TSL230RD programmable light-to-frequency converter combines a configurable silicon photodiode and a
current-to-frequency converter on single monolithic CMOS integrated circuit. The output can be either a pulse
train or a square wave (50% duty cycle) with frequency directly proportional to light intensity. Device sensitivity
is selectable in three ranges, providing two decades of adjustment. The full-scale output frequency can be
scaled by one of four preset values. All inputs and the output are TTL compatible, allowing direct two-way
communication with a microcontroller for programming and output interface. The output enable (OE) places the
output in the high-impedance state for multiple-unit sharing of a microcontroller input line.
The device has been temperature compensated for the ultraviolet-to-visible light range of 320 nm to 700 nm
and responds over the light range of 320 nm to 1050 nm. It is characterized over the temperature range of -25
C
to 70
C.
Functional Block Diagram
Light
Current-to-Frequency
Converter
Photodiode Array
S0
S1
S2
S3
OE
Output
r
r
Texas Advanced Optoelectronic Solutions Inc.
800 Jupiter Road, Suite 205
S
Plano, TX 75074
S
(972) 673-0759
8 S3
7 S2
6 OUT
5 V
DD
PACKAGE D
8-LEAD SOIC
(TOP VIEW)
S0
1
S1 2
OE 3
GND 4
TSL230RD
PROGRAMMABLE LIGHT-TO-FREQUENCY CONVERTER
TAOS054A - NOVEMBER 2003
2
r
r
Copyright
E
2003, TAOS Inc.
The
LUMENOLOGY
r
Company
www.taosinc.com
Terminal Functions
TERMINAL
TYPE
DESCRIPTION
NAME
NO.
TYPE
DESCRIPTION
GND
4
Ground
OE
3
I
Enable for f
O
(active low)
OUT
6
O
Scaled-frequency (f
O
) output
S0, S1
1, 2
I
Sensitivity-select inputs
S2, S3
7, 8
I
f
O
scaling-select inputs
V
DD
5
Supply voltage
Selectable Options
S1
S0
SENSITIVITY
S3
S2
f
O
SCALING (divide-by)
L
L
Power down
L
L
1
L
H
1
L
H
2
H
L
10
H
L
10
H
H
100
H
H
100
Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted)
Supply voltage, V
DD
(see Note 1)
6 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input voltage range, all inputs, V
I
- 0.3 V to V
DD
+ 0.3 V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating free-air temperature range, T
A
- 25
C to 70
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Storage temperature range
- 25
C to 85
C
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solder conditions in accordance with JEDEC J-STD-020A, maximum temperature
240
C
. . . . . . . . . . . . . . .
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: All voltage values are with respect to GND.
Recommended Operating Conditions
MIN
NOM
MAX
UNIT
Supply voltage, V
DD
2.7
5
5.5
V
High-level input voltage, V
IH
V
DD
= 4.5 V to 5.5 V
2
V
DD
V
Low-level input voltage, V
IL
V
DD
= 4.5 V to 5.5 V
0
0.8
V
Operating free-air temperature range, T
A
- 25
70
C
TSL230RD
PROGRAMMABLE LIGHT-TO-FREQUENCY CONVERTER
TAOS054A - NOVEMBER 2003
3
The
LUMENOLOGY
r
Company
r
r
Copyright
E
2003, TAOS Inc.
www.taosinc.com
Electrical Characteristics at T
A
= 25
C, V
DD
= 5 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
V
OH
High-level output voltage
I
OH
= -4 mA
4
4.5
V
V
OL
Low-level output voltage
I
OL
= 4 mA
0.25
0.4
V
I
IH
High-level input current
5
A
I
IL
Low-level input current
5
A
I
Supply current
Power-on mode
2
3
mA
I
DD
Supply current
Power-down mode
5
12
A
F.S.
Full-scale frequency (See Note 2)
S0=S1=H, S2=S3=L
1.1
MHz
Temperature coefficient of output frequency
700 nm (See Note 3)
200
ppm/
C
k
SVS
Supply voltage sensitivity
V
DD
= 5 V
10%
0.5
%/V
NOTES: 2. Full-scale frequency is the maximum operating frequency of the device without saturation.
3. The temperature coefficient of output frequency is measured with constant irradiance as the temperature is varied between -25
C
and 70
C. The constant irradiance is sufficiently high that the output frequency is much greater than the dark frequency over the
entire temperature range.
Operating Characteristics at V
DD
= 5 V, T
A
= 25
C, E
e
= 126
W/cm
2
,
p
= 640 nm (unless otherwise
noted)
PARAMETER
TEST CONDITIONS
TSL230RD
UNIT
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
S0 = S1 = H, S2 = S3 = L
80
100
120
kHz
S1 = H, S0 = S2 = S3 = L
8
10
12
kHz
f
O
Output frequency
S0 = H, S1 = S2 = S3 = L
0.8
1
1.2
kHz
f
O
Output frequency
S0 = S1 = S2 = H, S3 = L
40
50
60
kHz
S0 = S1 = S3 = H, S2 = L
8
10
12
kHz
S0 = S1 = S2 = S3 = H
0.8
1
1.2
kHz
f
D
Dark frequency
E
e
= 0,
S0 = S1 = H, S2 = S3 = L
0.4
10
Hz
R
e
Responsivity
S0 = S1 = H, S2 = S3 = L
0.79
kHz/
(
W/cm
2
)
t
Output pulse duration
S2 = S3 = L
125
600
ns
t
w
Output pulse duration
S2 or S3 = H
1/2f
O
s
f
O
= 0 MHz to 10 kHz
0.1%
%F.S.
Nonlinearity (See Notes 4 and 5)
f
O
= 0 MHz to 100 kHz
0.2%
%F.S.
Nonlinearity (See Notes 4 and 5)
f
O
= 0 MHz to 1 MHz
0.5%
%F.S.
Recovery from power down
100
s
Step response to full-scale step input
1 pulse of new frequency
plus 1
s
Response time to programming change
2 periods of new principal
frequency
plus 1
s
(Note 6)
Response time to output enable (OE)
50
150
ns
NOTES: 4. Nonlinearity is defined as the deviation of f
O
from a straight line between zero and full scale, expressed as a percent of full scale.
5. Nonlinearity test condition: S0 = S1 = H, S2 = S3 = L.
6. Principal frequency is the internal oscillator frequency, equivalent to divide-by-1 output selection.
TSL230RD
PROGRAMMABLE LIGHT-TO-FREQUENCY CONVERTER
TAOS054A - NOVEMBER 2003
4
r
r
Copyright
E
2003, TAOS Inc.
The
LUMENOLOGY
r
Company
www.taosinc.com
TYPICAL CHARACTERISTICS
Figure 1
OUTPUT FREQUENCY
vs
IRRADIANCE
E
e
- Irradiance -
W/cm
2
S0 = L, S1 = H
S0 = H, S1 = L
V
DD
= 5 V
p
= 640 nm
T
A
= 25
C
S2 = S3 = L
S0 = H, S1 = H
Output Frequency (f
O
- f
D
) -- kHz
0.001
0.01
0.1
1
10
100
1000
0.001 0.01 0.1
1
10
100
100k
1k
10k
1M
Figure 2
300
400
500
600
700
1000
800
900
1100
- Wavelength - nm
Normalized Responsivity
0
0.2
0.4
0.6
0.8
1.0
1.2
PHOTODIODE SPECTRAL RESPONSIVITY
Figure 3
DARK FREQUENCY
vs
TEMPERATURE
T
A
- Temperature -
C
-25
0
25
50
75
0
0.2
0.4
0.6
0.8
1
1.2
f
D
-- Dark Frequency -- Hz
V
DD
= 5 V
E
e
= 0
S0 = S1 = H
S2 = S3 = L
Figure 4
- Wavelength of Incident Light - nm
V
DD
= 5 V
TEMPERATURE COEFFICIENT
OF OUTPUT FREQUENCY
vs
WAVELENGTH OF INCIDENT LIGHT
0
1000
2000
3000
4000
5000
6000
7000
300
400
500
600
700
1000
800
900
T
emperature
Coefficient of Output Frequency -- ppm/
5
C
TSL230RD
PROGRAMMABLE LIGHT-TO-FREQUENCY CONVERTER
TAOS054A - NOVEMBER 2003
5
The
LUMENOLOGY
r
Company
r
r
Copyright
E
2003, TAOS Inc.
www.taosinc.com
TYPICAL CHARACTERISTICS
OUTPUT FREQUENCY
vs
SUPPLY VOLTAGE
V
DD
- Supply Voltage - V
Normalized Output Frequency
2.5
3
3.5
4
4.5
5
0.980
0.985
0.990
0.995
1.000
1.005
1.010
5.5
T
A
= 25
C
f
O
= 100 kHz
Figure 5
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