ETC TSL257

TSL257
HIGHSENSITIVITY
LIGHTTOVOLTAGE CONVERTER
TAOS023A – JULY 2000
Converts Light Intensity to Output Voltage
Monolithic Silicon IC Containing
PACKAGE
(FRONT VIEW)
Photodiode, Operational Amplifier, and
Feedback Components
High Sensitivity
Single Voltage Supply Operation (2.7 V to
5.5 V)
Low Noise (200 µVrms Typ to 1 kHz)
Rail-to-Rail Output
High Power-Supply Rejection (35 dB at
1 kHz)
Compact 3-Leaded Plastic Package
1
2
3
GND VDD
OUT
Description
The TSL257 is a high-sensitivity low-noise light-to-voltage optical converter that combines a photodiode and
a transimpedance amplifier on a single monolithic CMOS integrated circuit. Output voltage is directly
proportional to light intensity (irradiance) on the photodiode. The TSL257 has a transimpedance gain of 320 MΩ.
The device has improved offset voltage stability and low power consumption and is supplied in a 3-lead clear
plastic sidelooker package with an integral lens.
Functional Block Diagram
–
Voltage
Output
+
Terminal Functions
TERMINAL
NAME
DESCRIPTION
NO.
GND
1
Ground (substrate). All voltages are referenced to GND.
OUT
3
Output voltage
VDD
2
Supply voltage
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Copyright 2001, TAOS Inc.
Texas Advanced Optoelectronic Solutions Inc.
800 Jupiter Road, Suite 205 Plano, TX 75074 (972) 673-0759
1
TSL257
HIGHSENSITIVITY
LIGHTTOVOLTAGE CONVERTER
TAOS023A – JULY 2000
Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage, VDD (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 V
Output current, IO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±10 mA
Duration of short-circuit current at (or below) 25°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 s
Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –25°C to 85°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –25°C to 85°C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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 voltages are with respect to GND.
Recommended Operating Conditions
Supply voltage, VDD
Operating free-air temperature, TA
MIN
MAX
UNIT
2.7
5.5
V
0
70
°C
Electrical Characteristics at VDD = 5 V, TA = 25°C, λp = 470 nm, RL = 10 kΩ (unless otherwise noted)
(see Notes 2 and 3)
PARAMETER
VD
TEST CONDITIONS
Dark voltage
MIN
Ee = 0
TYP
0
VDD = 4.5 V,
No Load
VDD = 4.5 V,
RL = 10 kΩ
15
Maximum output voltage swing
VO
Output voltage
Ee = 1.54 µW/cm2, λp = 470 nm, Note 5
αVD
Temperature coefficient of dark voltage (VD)
TA = 0°C to 70°C
–15
λp = 428 nm, see Notes 4 and 8
1.18
λp = 470 nm, see Notes 5 and 8
1.30
λp = 565 nm, see Notes 6 and 8
1.58
λp = 645 nm, see Notes 7 and 8
1.68
Irradiance responsivity
PSRR
Power supply
y rejection
j
ratio
IDD
Supply current
UNIT
mV
4.49
VOM
Ne
MAX
fac = 100 Hz, see Note 9
4
4.2
1.6
2
V
2.4
µV/°C
V/( W/cm2)
V/(µW/cm
55
fac = 1 kHz, see Note 9
35
Ee = 1.54 µW/cm2, λp = 470 nm, Note 5
1.9
V
dB
dB
3.5
mA
NOTES: 2. Measured with RL = 10 kΩ between output and ground.
3. Optical measurements are made using small-angle incident radiation from a light-emitting diode (LED) optical source.
4. The input irradiance is supplied by a GaN/SiC light-emitting diode with the following characteristics: peak wavelength λp = 428 nm,
spectral halfwidth ∆λ½ = 65 nm.
5. The input irradiance is supplied by an InGaN light-emitting diode with the following characteristics: peak wavelength λp = 470 nm,
spectral halfwidth ∆λ½ = 35 nm.
6. The input irradiance is supplied by a GaP light-emitting diode with the following characteristics: peak wavelength λp = 565 nm,
spectral halfwidth ∆λ½ = 28 nm.
7. The input irradiance is supplied by an AlGaAs light-emitting diode with the following characteristics: peak wavelength λp = 645 nm,
spectral halfwidth ∆λ½ = 25 nm.
8. Irradiance responsivity is characterized over the range VO = 0.1 V to 4.5 V. The best-fit straight line of Output Voltage VO versus
Irradiance Ee over this range will typically have a positive extrapolated VO value for Ee = 0.
9. Power supply rejection ratio PSRR is defined as 20 log (∆VDD(f)/∆VO(f)) with VDD(f = 0) = 5 V and VO(f = 0) = 2 V.
Copyright 2001, TAOS Inc.
2
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TSL257
HIGHSENSITIVITY
LIGHTTOVOLTAGE CONVERTER
TAOS023A – JULY 2000
Switching Characteristics at VDD = 5 V, TA = 25°C, λp = 470 nm, RL = 10 kΩ (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
tr
Output pulse rise time, 10% to 90% of final value
See Note 10 and Figure 1
160
250
µs
tf
Output pulse fall time, 10% to 90% of final value
See Note 10 and Figure 1
150
250
µs
ts
Output settling time to 1% of final value
See Note 10 and Figure 1
330
µs
Integrated noise voltage
f = dc to 1 kHz
Ee = 0
200
µVrms
f = 10 Hz
Ee = 0
6
f = 100 Hz
Ee = 0
6
f = 1 kHz
Ee = 0
7
Vn
Output noise voltage,
g , rms
µV/√Hz
µ
√ rms
NOTE 10: Switching characteristics apply over the range VO = 0.1 V to 4.5 V.
PARAMETER MEASUREMENT INFORMATION
VDD
Pulse
Generator
Ee
2
Input
LED
(see Note A)
–
3
tf
tr
Output
+
90%
RL
TSL257
1
Output
(see Note B)
10%
90%
10%
VOLTAGE WAVEFORM
TEST CIRCUIT
NOTES: A. The input irradiance is supplied by a pulsed InGaN light-emitting diode with the following characteristics: λp = 470 nm,
tr < 1 µs, tf < 1 µs.
B. The output waveform is monitored on an oscilloscope with the following characteristics: tr < 100 ns, Zi ≥ 1 MΩ, Ci ≤ 20 pF.
Figure 1. Switching Times
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Copyright 2001, TAOS Inc.
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TSL257
HIGHSENSITIVITY
LIGHTTOVOLTAGE CONVERTER
TAOS023A – JULY 2000
TYPICAL CHARACTERISTICS
POWER SUPPLY REJECTION RATIO
vs
FREQUENCY
PHOTODIODE SPECTRAL RESPONSIVITY
1.6
80
Normalized to
470 nm
TA = 25°C
Power Supply Rejection Ratio — dB
1.4
Relative Responsivity
1.2
1.0
0.8
0.6
0.4
0.2
70
60
50
40
30
20
10
0
300
0
500
700
900
λ – Wavelength – nm
1100
102
10
Figure 2
0.9
8
0.8
Normalized Response
V D– Dark Voltage – mV
1.0
9
7
6
5
4
3
0.7
0.6
0.5
0.4
0.3
2
0.2
1
0.1
0
10
30
50
20
40
60
TA – Free-Air Temperature – °C
70
0
–90
–70
–50
–30 –10
10
30
50
Angular Displacement – Figure 4
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4
106
NORMALIZED RESPONSE
vs
ANGULAR DISPLACEMENT
VDD = 5 V
0
105
Figure 3
DARK VOLTAGE
vs
FREE-AIR TEMPERATURE
10
103
104
f – Frequency – Hz
70
90
Figure 5
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TSL257
HIGHSENSITIVITY
LIGHTTOVOLTAGE CONVERTER
TAOS023A – JULY 2000
MECHANICAL DATA
The TSL257 is implemented in a clear 3-leaded package with a molded focusing lens.
0.072 (1,84)
0.057 (1,44)
0.189 (4,80)
0.173 (4,40)
0.165 (4,20)
0.150 (3,80)
0.032 (0,80)
0.016 (0,40)
0.071 (1,80)
R 0.035 (0,90)
0.071 (1,8)
0.110 (2,80)
0.016 (0,40)
0.189 (4,80)
0.173 (4,40)
0.029 (0,75)
0.079 (2,00)
0.039 (1,00)
0.027 (0,70)
0.102 (2,6)
0.026 (0,65)
0.630 (16,00)
0.531 (13,50)
0.018 (0,45)
0.018 (0,45)
0.079 (2,00)
0.079 (2,00)
Figure 6. Package Configuration
NOTES: A.
B.
C.
D.
E.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
All dimensions apply before solder dip.
Package body is a clear nonfilled optically transparent material
Index of refraction of clear plastic is 1.55.
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Copyright 2001, TAOS Inc.
5
TSL257
HIGHSENSITIVITY
LIGHTTOVOLTAGE CONVERTER
TAOS023A – JULY 2000
PRODUCTION DATA — information in this document is current at publication date. Products conform to
specifications in accordance with the terms of Texas Advanced Optoelectronic Solutions, Inc. standard
warranty. Production processing does not necessarily include testing of all parameters.
NOTICE
Texas Advanced Optoelectronic Solutions, Inc. (TAOS) reserves the right to make changes to the products contained in this
document to improve performance or for any other purpose, or to discontinue them without notice. Customers are advised
to contact TAOS to obtain the latest product information before placing orders or designing TAOS products into systems.
TAOS assumes no responsibility for the use of any products or circuits described in this document or customer product
design, conveys no license, either expressed or implied, under any patent or other right, and makes no representation that
the circuits are free of patent infringement. TAOS further makes no claim as to the suitability of its products for any particular
purpose, nor does TAOS assume any liability arising out of the use of any product or circuit, and specifically disclaims any
and all liability, including without limitation consequential or incidental damages.
TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS, INC. PRODUCTS ARE NOT DESIGNED OR INTENDED FOR
USE IN CRITICAL APPLICATIONS IN WHICH THE FAILURE OR MALFUNCTION OF THE TAOS PRODUCT MAY
RESULT IN PERSONAL INJURY OR DEATH. USE OF TAOS PRODUCTS IN LIFE SUPPORT SYSTEMS IS EXPRESSLY
UNAUTHORIZED AND ANY SUCH USE BY A CUSTOMER IS COMPLETELY AT THE CUSTOMER’S RISK.
TAOS, the TAOS logo, and Texas Advanced Optoelectronic Solutions are trademarks of Texas Advanced Optoelectronic Solutions
Incorporated.
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