Data Sheet

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The technical content of this TAOS datasheet is still valid.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
r
r
TAOS029L − OCTOBER 2007
D Converts Light Intensity to Digital Signal
D Infrared Compensation to Approximate
PACKAGE D
8-LEAD SOIC
(TOP VIEW)
Human Eye Response
Rejects 50 Hz/60 Hz Lighting Ripple
Two-Wire SMBus Serial Interface
Single Supply Operation (2.7 V to 5.5 V)
Low Active Power (1 mW typ)
Power Down Mode
Low-Profile Surface-Mount Packages
RoHS Compliant
8 SMBData
VDD 1
NC 2
7 NC
NC 3
6 NC
5 SMBCLK
GND 4
PACKAGE T
4-LEAD SMD
(TOP VIEW)
Description
VDD 1
The TSL2550 is a digital-output light sensor with
a two-wire, SMBus serial interface. It combines
two photodiodes and a companding analog-todigital converter (ADC) on a single CMOS
integrated circuit to provide light measurements
over an effective 12-bit dynamic range with a
response similar to that of the human eye.
4 SMBData
3 SMBCLK
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GND 2
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Companding A/D for Wide Dynamic Range
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D
D
D
D
D
D
D
D
The TSL2550 is designed for use with broad wavelength light sources. One of the photodiodes (channel 0) is
sensitive to visible and infrared light, while the second photodiode (channel 1) is sensitive primarily to infrared
light. An integrating ADC converts the photodiode currents to channel 0 and channel 1 digital outputs. Channel
1 digital output is used to compensate for the effect of the infrared component of ambient light on channel 0
digital output. The ADC digital outputs of the two channels are used to obtain a value that approximates the
human eye response in the commonly used unit of Lux.
This device is intended primarily for use in applications in which measurement of ambient light is used to control
display backlighting such as laptop computers, PDAs, camcorders, and GPS systems. Other applications
include contrast control in LED signs and displays, camera exposure control, lighting controls, etc. The
integrating conversion technique used by the TSL2550 effectively eliminates the effect of flicker from
AC-powered lamps, increasing the stability of the measurement.
ca
Functional Block Diagram
Integrating
A/D Converter
ni
Channel 0
Photodiode
ch
Channel 1
Photodiode
Te
VDD = 2.7 V to 5.5 V
Control Logic
Output Registers
Two-Wire Serial Interface
SMBCLK
SMBData
The LUMENOLOGY r Company
Copyright E 2007, TAOS Inc.
r
Texas Advanced Optoelectronic Solutions Inc.
1001 Klein Road S Suite 300 S Plano, TX 75074 S (972)
r 673-0759
www.taosinc.com
1
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
Terminal Functions
TERMINAL
T PKG
NO.
TYPE
GND
4
2
SMBCLK
5
3
I
SMBData
8
4
I/O
VDD
1
1
DESCRIPTION
Power supply ground. All voltages are referenced to GND.
SMBus serial clock input terminal — clock signal for SMBus serial data.
SMBus serial data I/O terminal — serial data I/O for SMBus.
Supply voltage.
al
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D PKG
NO.
NAME
Available Options
TA
PACKAGE − LEADS
PACKAGE DESIGNATOR
−40°C to 85°
SOIC−8
D
TSL2550
−40°C to 85°
T−4
T
TSL2550D
TSL2550T
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TSL2550
ORDERING NUMBER
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DEVICE
Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage, VDD (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 V
Digital output voltage range, VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to +6 V
Digital output current, IO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±10 mA
SMBus input/output current, I(SMBIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −1 mA to 20 mA
Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −40°C to 85°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −40°C to 85°C
ESD tolerance, human body model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2000 V
Solder conditions in accordance with JEDEC J−STD−020A, maximum temperature (see Note 2) . . . 260°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.
ca
NOTES: 1. All voltage values are with respect to GND.
2. Package D only: The device may be hand soldered provided that heat is applied only to the solder pad and no contact is made
between the tip of the solder iron and the device lead. The maximum time heat should be applied to the device is 5 seconds.
Recommended Operating Conditions
ni
Supply voltage, VDD
Operating free-air temperature, TA
MIN
MAX
2.7
5.5
V
70
°C
0.8
V
0
ch
SMBus input low voltage @ VDD = 3.3 V ± 5%, VIL
2.1
SMBus operating frequency, f(SMBCLK)
10
V
100
kHz
Te
SMBus input high voltage @ VDD = 3.3 V ± 5%, VIH
UNIT
Copyright E 2007, TAOS Inc.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
Electrical Characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
SMBus output low voltage
TYP
IO = 4 mA
0.4
Active, VSMBCLK and VSMDATA = VDD,
VDD = 3.3 V ± 5%
Supply current
0.35
Power down, VSMBCLK and VSMDATA =
VDD, VDD = 3.3 V ± 5%
IIH
High level input current
VI = VDD
IIL
Low level input current
VI = 0
MAX
0.01
UNIT
V
0.6
mA
10
μA
5
μA
−5
μA
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IDD
MIN
lv
VOL
TEST CONDITIONS
IO = 50 μA
Operating Characteristics, VDD = 3.3 V, TA = 25C (unless otherwise noted) (see Notes 2, 3, 4)
PARAMETER
TEST CONDITIONS
CHANNEL
Ch0
ADC count value,
value standard mode
Ch1
λp = 640 nm
Ee = 72 μW/cm2
Ch0
λp = 940 nm
Ee = 140 μW/cm2
Ch0
ADC count value,
value extended mode
ca
ch
(Sensor Lux) / (actual Lux), standard mode
(Note 5)
799
Ch1
Ch0
155
Ch1
16
λp = 940 nm
Ee = 140 μW/cm2
Ch0
155
Ch1
μW/cm2
959
counts
1039
1
1
counts
139
0.106
0.175
0.70
0.88
1.20
λp = 640 nm
Ee = 72 μW/cm2
11.1
Ch1
1.2
λp = 940 nm
Ee = 140 μW/cm2
Ch0
5.7
Ch1
5
Incandescent light source: 50 Lux
1
0.070
Ch0
Fluorescent light source: 300 Lux
UNIT
1
703
Ch0
Illuminance responsivity,
responsivity standard mode
ni
Rv
511
λp = 640 nm
Ee = 72 μW/cm2
λp = 940 nm, Ee = 140
Irradiance responsivity,
responsivity standard mode
799
MAX
85
Ch1
λp = 640 nm, Ee = 72 μW/cm2
ADC count value ratio: Ch1/Ch0,
standard mode
639
Ch1
Ee = 0
Re
TYP
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Ee = 0
MIN
Ch0
2.8
Ch1
0.23
Ch0
19
Ch1
counts/
(μW/
cm2)
counts/
lux
13
Fluorescent light source: 300 Lux
0.65
1
1.35
Incandescent light source: 50 Lux
0.5
1
1.5
Te
NOTES: 3. Optical measurements are made using small-angle incident radiation from light-emitting diode optical sources. Visible 640 nm LEDs
and infrared 940 nm LEDs are used for final product testing for compatibility with high volume production.
4. The 640 nm irradiance Ee is supplied by an AlInGaP light-emitting diode with the following characteristics: peak wavelength
λp = 640 nm and spectral halfwidth Δλ½ = 17 nm.
5. The 940 nm irradiance Ee is supplied by a GaAs light-emitting diode with the following characteristics: peak wavelength
λp = 940 nm and spectral halfwidth Δλ½ = 40 nm.
6. The sensor Lux is calculated using the empirical formula shown on p. 11 of this data sheet based on measured Ch0 and Ch1 ADC
count values for the light source specified. Actual Lux is obtained with a commercial luxmeter. The range of the (sensor Lux) / (actual
Lux) ratio is estimated based on the variation of the 640 nm and 940 nm optical parameters. Devices are not 100% tested with
fluorescent or incandescent light sources.
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3
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
AC Electrical Characteristics, VDD = 3.3 V, TA = 25C (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
t(CONV)
Conversion time, per channel, standard mode
400
ms
t(CONV)
Conversion time, per channel, extended mode
80
ms
f(SMBCLK)
Clock frequency
t(BUF)
Bus free time between start and stop condition
4.7
μs
t(HDSTA)
Hold time after (repeated) start condition. After
this period, the first clock is generated.
4
μs
t(SUSTA)
Repeated start condition setup time
t(SUSTO)
Stop condition setup time
t(HDDAT)
Data hold time
300
t(SUDAT)
Data setup time
250
t(LOW)
SMBCLK clock low period
4.7
t(HIGH)
SMBCLK clock high period
t(TIMEOUT)
Detect clock/data low timeout
tF
Clock/data fall time
tR
Clock/data rise time
Ci
Input pin capacitance
4.7
μs
μs
ns
ns
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4
kHz
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100
μs
4
μs
35
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25
300
ms
ns
ns
10
pF
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1000
Copyright E 2007, TAOS Inc.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
PARAMETER MEASUREMENT INFORMATION
t(LOW)
t(R)
t(F)
VIH
SMBCLK
VIL
t(HDSTA)
t(BUF)
t(HIGH)
t(SUSTA)
t(HDDAT)
t(SUSTO)
t(SUDAT)
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VIH
SMBDATA
VIL
S
S
Start
Condition
Start
P
Stop
t(LOWSEXT)
SMBCLKACK
SMBCLKACK
t(LOWMEXT)
t(LOWMEXT)
lv
P
Stop
Condition
t(LOWMEXT)
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SMBCLK
SMBDATA
Figure 1. SMBus Timing Diagrams
1
9
SMBCLK
A6
SMBDATA
A5
Start by
Master
A4
A3
A2
A1
A0
R/W
1
D7
D6
D5
D4
D3
D2
D1
ACK by
TSL2550
9
D0
ACK by Stop by
TSL2550 Master
Frame 1 SMBus Slave Address Byte
Frame 2 Command Byte
1
A6
A5
A4
ch
SMBDATA
ni
SMBCLK
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Figure 2. SMBus Timing Diagram for Send Byte Format
A3
A2
A1
9
A0
R/W
Te
Start by
Master
1
D7
9
D6
D5
D4
D3
D2
ACK by
TSL2550
Frame 1 SMBus Slave Address Byte
D1
D0
NACK by Stop by
Master Master
Frame 2 Data Byte From TSL2550
Figure 3. SMBus Timing Diagram for Receive Byte Format
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5
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
TYPICAL CHARACTERISTICS
NORMALIZED ADC OUTPUT
vs.
SUPPLY VOLTAGE
SPECTRAL RESPONSIVITY
1.8
1
0.4
Channel 1
Photodiode
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0.6
1.4
1.2
1
0.8
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Channel 0
Photodiode
0.6
0.4
0.2
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Relative Responsivity
0.8
Normalized ADC Output
1.6
0.2
0
400
500
600
700
800
900
1000
1100
0
2.5
3
3.5
4
4.5
5
5.5
6
VDD − Supply Voltage − V
λ − Wavelength − nm
Figure 4
Te
ch
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Figure 5
Copyright E 2007, TAOS Inc.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
PRINCIPLES OF OPERATION
Analog-to-Digital Converter
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The TSL2550 contains an integrating analog-to-digital converter (ADC) that integrates a photodiode current.
First it integrates channel 0 photodiode current and then it integrates channel 1 photodiode current. At the end
of the conversion cycle for each channel, the conversion result is transferred to the appropriate channel 0 or
channel 1 ADC register. The transfer is double-buffered to ensure that invalid data is not read during the transfer.
After the data is transferred, the TSL2550 automatically begins the next conversion cycle. A VALID bit is used
to indicate that data has been written to the ADC register after ADC is enabled.
Interface to the ADC and control of other device functions is accomplished using the standard 2-wire System
Management Bus (SMBus) interface. Both versions 1.1 and 2.0 of the SMBus are supported.
Digital Interface
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The ADC has two operating modes: standard and extended. In standard mode, the integration time is 400 mS
for each channel or 800 mS for both channel 0 and channel 1. Extended mode shortens the integration time
by a factor of five with a corresponding decrease in responsivity of 5 ×. The extended range allows the device
to operate at higher light levels, extending the overall dynamic range by a factor of five.
The TSL2550 contains an 8-bit command register that can be written and read via the SMBus. The command
register controls the overall operation of the device. There are two read-only registers that contain the latest
converted value of each of the two ADC channels. The SMBus slave address is hardwired internally as 0111001
(MSB to LSB, A6 to A0).
Both the send byte protocol and the receive byte protocol are implemented in the TSL2550. The send byte
protocol allows single bytes of data to be written to the device (see Figure 6). The written byte is called the
COMMAND byte. The receive byte protocol allows single bytes of data to be read from the device (see Figure
7). The receive data can be either the previously written COMMAND byte or the data from one of the ADC
channels. In Figure 6 and Figure 7, the clear area represents data sent by the host and the shaded area
represents data returned by the ambient light sensor or slave device.
7
1
1
8
1
1
S
Slave Address
WR
A
Data Byte
A
P
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1
S = Start Condition
P = Stop Condition
Shaded = Slave Transmission
1
7
1
1
8
1
1
S
Slave Address
RD
A
Data Byte
A
P
S = Start Condition
Te
ch
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Figure 6. Send Byte Protocol
The LUMENOLOGY r Company
P = Stop Condition
Shaded = Slave Transmission
Figure 7. Receive Byte Protocol
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
Command Register
The command register is used primarily to:
D Select which ADC register will be read during a read cycle
D Switch the dynamic range of the device between standard and extended range modes
D Power the device up for operation or power it down for minimum power consumption
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Table 1 shows the six primary commands used to control the TSL2550.
Table 1. Command Summary
FUNCTION
Power-down state
0x03h
Power-up state/Read command register
0x1Dh
Write command to assert extended range mode
0x18h
Write command to reset or return to standard range mode
0x43h
Read ADC channel 0
0x83h
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0x00h
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COMMAND
Read ADC channel 1
The content of the command register defaults to 0x00h when power is applied to the device, placing the device
into the power-down mode.
Once the TSL2550 is set to the standard range mode (0x18h) or the extended range mode (0x1Dh), the device
remains in that mode until it is powered down or the mode is changed via the command register.
The 0x03h command has two purposes: It is used to power up the device and can also be used to check that
the device is communicating properly. The value returned during a read cycle should be 0x03h.
ADC Register
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The TSL2550 contains two ADC registers (channel 0 and channel 1). Each ADC register contains two
component fields that are used to determine the logarithmic ADC count value: CHORD bits and STEP bits. The
CHORD bits correspond to the most significant portion of the ADC value and specifies a segment of the
piece-wise linear approximation. The STEP bits correspond to the least significant portion of the ADC count
value and specifies a linear value within a segment. CHORD and STEP bits all equal to 0 corresponds to a
condition in which the light level is below the detection limit of the sensor. CHORD and STEP bits all equal to
1 corresponds to an overflow condition.
Each of the two ADC value registers contain seven data bits and a valid bit as described in Table 2.
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Table 2. ADC Register Data Format
VALID
CHORD BITS
B6
ch
B7
B4
B3
B2
B1
B0
C1
C0
S3
S2
S1
S0
C2
FIELD
BITS
VALID
7
CHORD
6 to 4
CHORD number.
STEP
3 to 0
STEP number.
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VALID
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8
STEP BITS
B5
DESCRIPTION
ADC channel data is valid. One indicates that the ADC has written data into the
channel data register, since ADCEN was asserted in the COMMAND register.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
The specific ADC value register read depends on the last read command written to the command register, as
described above and in the Operation section, below.
The MSB of the ADC register (VALID bit B7) is used to indicate that data has been written to the ADC register
after the device is powered up as described in Command Register section.
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Bits 6 through 0 contain the 7-bit code representing the ADC count value, which is proportional to a
photodetector current. In this code, the ADC count value is represented by a piece-wise linear approximation
to a log function. The transfer function is broken into 8 chords of 16 steps each. (This code is very similar to μ-law
code used in audio compression — it differs in that it does not have a sign bit and it is not inverted.) Table 3 shows
the relationship between the CHORD and STEP bits and the CHORD and STEP numbers and values. These
are used to calculate the ADC count value.
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Table 3. CHORD and STEP Numbers and Values vs Register Bits
C, CHORD
NUMBER
CHORD
VALUE
(Note A)
STEP
VALUE
(Note B)
STEP
BITS
B3, B2, B1, B0
S, STEP
NUMBER
000
0
0
1
0000
0
001
010
011
100
101
110
111
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CHORD
BITS
B6, B5, B4
1
16
2
0001
1
2
49
4
0010
2
3
115
8
0011
3
4
247
16
0100
4
5
511
32
0101
5
6
1039
64
0110
6
7
2095
128
0111
7
1000
8
1001
9
1010
10
1011
11
1100
12
1101
13
1110
14
1111
15
ca
NOTES: A. CHORD VALUE = INT (16.5 × ((2C) − 1))
B. STEP VALUE = 2C
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The ADC count value is obtained by adding the CHORD VALUE and the product of the STEP NUMBER and
STEP VALUE (which depends on CHORD NUMBER).
ch
ADC Count Value + ((Chord Value) ) (Step Value)
(Step Number))
The ADC count value can also be expressed as a formula:
ADC Count Value + (INT (16.5
((2 C * 1))) ) (S
(2 C))
Te
where:
C
is the CHORD NUMBER (0 to 7)
S
is the STEP NUMBER (0 to 15)
as defined in Table 3.
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9
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
Operation
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After applying VDD, the device will initially be in the power down state. To operate the device, issue an SMBus
Send Byte protocol with the device address and the appropriate command byte to read ADC channel 0 or ADC
channel 1 (see Table 1). To obtain the conversion result, issue an SMBus Receive Byte protocol with the device
address. The data byte received will correspond to the value in the ADC register (0 or 1) specified by the previous
command. If a conversion has not been completed since power up (either through VDD or power up command),
the valid bit will be 0, and the data will not be valid. If there is a valid conversion result available, the valid bit
will be set (1), and the remaining 7 bits will represent valid data from the previously selected ADC register. Data
may be read repeatedly from the currently selected ADC register, and although it will remain valid, the ADC
register will not be updated until a new conversion completes for that channel (800 ms total since there are two
serial 400 ms per channel conversion times in standard mode). Note also that the command register itself may
be read, as a check to be sure that the device is communicating properly.
Te
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To power down the device for reduced power consumption, issue an SMBus Send Byte protocol with the device
address followed by 0 as indicated in Table 1.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
APPLICATION INFORMATION
The TSL2550 is intended for use in ambient light detection applications, such as display backlight control, where
adjustments are made to display brightness or contrast based on the brightness of the ambient light, as
perceived by the human eye. Conventional silicon detectors respond strongly to infrared light, which the human
eye does not see. This can lead to significant error when the infrared content of the ambient light is high, such
as with incandescent lighting, due to the difference between the silicon detector response and the brightness
perceived by the human eye.
where:
0.39
e (*0.181R
2)
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Light Level (lux) + (Ch0 * Ch1)
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This problem is overcome in the TSL2550 through the use of two photodiodes. One of the photodiodes
(channel 0) is sensitive to both visible and infrared light, while the second photodiode (channel 1) is sensitive
primarily to infrared light. An integrating ADC converts the photodiode currents to channel 0 and channel 1 digital
outputs. Channel 1 digital output is used to compensate for the effect of the infrared component of light on the
channel 0 digital output. The ADC digital outputs from the two channels are used in a formula to obtain a value
that approximates the human eye response in the commonly used Illuminance unit of Lux. For standard mode:
R = Ch1 Counts / (Ch0 Counts − Ch1 Counts)
The formula above was obtained by optical testing with fluorescent and incandescent light sources. The light
level calculated from the formula will be slightly higher than the actual light level for sunlight and will be slightly
lower than the actual light level for composite fluorescent and incandescent light sources.
NOTE:
Please see TAOS application notes for additional information, including implementing a display
brightness control system with the TSL2550, and for a simple implementation of the equation shown
above suitable for use in embedded microcontrollers.
Table 4 contains a summary of the typical sensor outputs for several common light sources.
Table 4. Sensor Output Summary (Standard Mode)
Fluorescent
Daylight (shade)
CHANNEL 0
(COUNTS)
CHANNEL 1
(COUNTS)
RATIO:
CH1/CH0
LUX per CH0
COUNT
297
201
831
68
0.082
0.36
895
343
0.383
42
0.22
959
671
0.7
0.04
ni
Incandescent
ILLUMINANCE
(LUX)
ca
LIGHT SOURCE
ch
Light from 50 or 60 Hz sources, and especially fluorescent lighting, has a high harmonic content. Since the
TSL2550 integrates the ambient light over an approximately 400 millisecond interval (per channel), this light
ripple is typically reduced to less than ¼ LSB.
Te
Power Supply Decoupling
The power supply lines must be decoupled with a 0.1 μF capacitor placed as close to the device package as
possible. The bypass capacitor should have low effective series resistance (ESR) and effective series
inductance (ESI), such as the common ceramic types, which provide a low impedance path to ground at high
frequencies to handle transient currents caused by internal logic switching.
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Copyright E 2007, TAOS Inc.
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11
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
APPLICATION INFORMATION
PCB Pad Layout
4.65
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Suggested PCB pad layout guidelines for the D package and T package are shown in Figure 8 and Figure 9.
1.27
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6.90
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st
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2.25
0.50
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
Figure 8. Suggested D Package PCB Layout
2.90
1.50
0.90
ca
1.00
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
Te
ch
ni
Figure 9. Suggested T Package PCB Layout
Copyright E 2007, TAOS Inc.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
MECHANICAL DATA
PACKAGE D
Plastic Small-Outline
BOTTOM VIEW
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TOP VIEW
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PIN 1
6 1.27
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PIN 1
SIDE VIEW
NOTE B
END VIEW
2.8 TYP
CLEAR WINDOW
8 0.510
0.330
5.00
4.80
0.50
0.25
45
5.3
MAX
0.88 TYP TOP OF
SENSOR DIE
A
1.75
1.35
ca
DETAIL A
4.00
3.80
6.20
5.80
ch
ni
0.25
0.19
Pb
1.27
0.41
0.25
0.10
Te
NOTES: A. All linear dimensions are in millimeters.
B. The center of the 1234 μm by 282 μm photo-active area is typically located in the center of the package in the long dimension and
269 μm off center in the short dimension.
C. Package is molded with an electrically nonconductive clear plastic compound having an index of refraction of 1.55.
D. This drawing is subject to change without notice.
Figure 10. Package D — Plastic Small Outline IC Packaging Configuration
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13
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
MECHANICAL DATA
PACKAGE T
Four-Lead Surface Mount Device
TOP VIEW
PHOTODIODE ACTIVE AREA LOCATION
0.28
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1.46
PIN 1
PIN 4
0.67
1.50
lv
1.23
SIDE VIEW
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0.55
0.50
1.35
0.35
DETAIL A: TYPICAL PACKAGE TERMINAL
2
3.10
7
0.10
0.90
0.78
BOTTOM VIEW
A
0.78
ca
R 0.25
PIN 1
ni
2.60
PIN 4
Pb
ch
3.80
All linear dimensions are in millimeters.
Terminal finish is gold.
Dimension tolerance is ± 0.15 mm.
This drawing is subject to change without notice.
Te
NOTES: A.
B.
C.
D.
Figure 11. Package T — Four-Lead Surface Mount Device Packaging Configuration
Copyright E 2007, TAOS Inc.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
MECHANICAL DATA
Ko
2.11 0.10 [0.083 0.004]
0.292 0.013
[0.0115 0.0005]
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SIDE VIEW
END VIEW
TOP VIEW
4 0.1
[0.157 0.004]
2 0.05
[0.079 0.002]
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1.75 0.10
[0.069 0.004]
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8 0.1
[0.315 0.004]
1.50
B
5.50 0.05
[0.217 0.002]
12 + 0.3 − 0.1
[0.472 + 0.12 − 0.004]
A
B
A
DETAIL A
5.13 0.10
[0.202 0.004]
Bo
All linear dimensions are in millimeters [inches].
The dimensions on this drawing are for illustrative purposes only. Dimensions of an actual carrier may vary slightly.
Symbols on drawing Ao, Bo, and Ko are defined in ANSI EIA Standard 481−B 2001.
Each reel is 178 millimeters in diameter and contains 1000 parts.
TAOS packaging tape and reel conform to the requirements of EIA Standard 481−B.
In accordance with EIA standard, device pin 1 is located next to the sprocket holes in the tape.
This drawing is subject to change without notice.
Figure 12. Package D Carrier Tape
Te
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NOTES: A.
B.
C.
D.
E.
F.
G.
6.45 0.10
[0.254 0.004]
ca
Ao
DETAIL B
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15
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
MECHANICAL DATA
2.10
0.30 0.050
SIDE VIEW
B
1.50
4 0.100
8 Typ
2 0.100
TOP VIEW
12 0.100
1.50
R 0.20 TYP
B
A
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5.50
0.100
A
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DETAIL B
DETAIL A
2.90 0.100 Ao
3.09 MAX
ni
4.10 0.100 Bo
ch
1.80 Ko
Te
All linear dimensions are in millimeters.
The dimensions on this drawing are for illustrative purposes only. Dimensions of an actual carrier may vary slightly.
Symbols on drawing Ao, Bo, and Ko are defined in ANSI EIA Standard 481−B 2001.
Each reel is 178 millimeters in diameter and contains 1000 parts.
TAOS packaging tape and reel conform to the requirements of EIA Standard 481−B.
In accordance with EIA standard, device pin 1 is located next to the sprocket holes in the tape.
This drawing is subject to change without notice.
Copyright E 2007, TAOS Inc.
16
R 0.20 TYP
4.29 MAX
ca
R 0.20 TYP
NOTES: A.
B.
C.
D.
E.
F.
G.
END VIEW
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1.75 0.100
Figure 13. Package T Carrier Tape
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
MANUFACTURING INFORMATION
The D and T packages have been tested and have demonstrated an ability to be reflow soldered to a PCB
substrate. The process, equipment, and materials used in these test are detailed below.
Table 5. TSL2550 Solder Reflow Profile
PARAMETER
REFERENCE
TSL2550D/TSL2550T
tsoak
2 to 3 minutes
Time above 217°C
t1
Max 60 sec
Time above 230°C
t2
Max 50 sec
Time above Tpeak −10°C
t3
Max 10 sec
Tpeak
260° C (−0°C/+5°C)
2.5°C/sec
Soak time
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Peak temperature in reflow
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Average temperature gradient in preheating
Temperature gradient in cooling
Max −5°C/sec
Not to scale — for reference only
T3
T2
Temperature (C)
T1
ca
Tpeak
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The solder reflow profile describes the expected maximum heat exposure of components during the solder
reflow process of product on a PCB. Temperature is measured on top of component. The components should
be limited to a maximum of three passes through this solder reflow profile.
t3
t2
tsoak
t1
ch
ni
Time (sec)
Te
Figure 14. TSL2550D/TSL2550T Solder Reflow Profile Graph
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17
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
MANUFACTURING INFORMATION
Moisture Sensitivity
Optical characteristics of the device can be adversely affected during the soldering process by the release and
vaporization of moisture that has been previously absorbed into the package molding compound.
Package D
al
id
To ensure the package molding compound contains the smallest amount of absorbed moisture possible, all
devices shipped in carrier tape have been pre-baked and shipped in a sealed moisture-barrier bag. No further
action is necessary if these devices are processed through solder reflow within 24 hours of the seal being broken
on the moisture-barrier bag.
lv
However, for all devices shipped in tubes or if the seal on the moisture barrier bag has been broken for 24 hours
or longer, it is recommended that the following procedures be used to ensure the package molding compound
contains the smallest amount of absorbed moisture possible.
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For devices shipped in tubes:
1. Remove devices from tubes
2. Bake devices for 4 hours, at 90°C
3. After cooling, load devices back into tubes
4. Perform solder reflow within 24 hours after bake
Bake only a quantity of devices that can be processed through solder reflow in 24 hours. Devices can be
re-baked for 4 hours, at 90°C for a cumulative total of 12 hours (3 bakes for 4 hours at 90°C).
For devices shipped in carrier tape:
1. Bake devices for 4 hours, at 90°C in the tape
2. Perform solder reflow within 24 hours after bake
Bake only a quantity of devices that can be processed through solder reflow in 24 hours. Devices can be
re−baked for 4 hours in tape, at 90°C for a cumulative total of 12 hours (3 bakes for 4 hours at 90°C).
Package T
ca
To ensure the package molding compound contains the smallest amount of absorbed moisture possible, each
device is dry-baked prior to being packed for shipping. Devices are packed in a sealed aluminized envelope
with silica gel to protect them from ambient moisture during shipping, handling, and storage before use.
ni
The T package has been assigned a moisture sensitivity level of MSL 3 and the devices should be stored under
the following conditions:
ch
Temperature Range
Relative Humidity
Total Time
Opened Time
5°C to 50°C
60% maximum
6 months from the date code on the aluminized envelope — if unopened
168 hours or fewer
Te
Rebaking will be required if the devices have been stored unopened for more than 6 months or if the aluminized
envelope has been open for more than 168 hours. If rebaking is required, it should be done at 90°C for 4 hours.
Copyright E 2007, TAOS Inc.
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TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
TAOS029L − OCTOBER 2007
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.
LEAD-FREE (Pb-FREE) and GREEN STATEMENT
al
id
Pb-Free (RoHS) TAOS’ terms Lead-Free or Pb-Free mean semiconductor products that are compatible with the current
RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous
materials. Where designed to be soldered at high temperatures, TAOS Pb-Free products are suitable for use in specified
lead-free processes.
lv
Green (RoHS & no Sb/Br) TAOS defines Green to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and
Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material).
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Important Information and Disclaimer The information provided in this statement represents TAOS’ knowledge and
belief as of the date that it is provided. TAOS bases its knowledge and belief on information provided by third parties,
and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate
information from third parties. TAOS has taken and continues to take reasonable steps to provide representative
and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and
chemicals. TAOS and TAOS suppliers consider certain information to be proprietary, and thus CAS numbers and other
limited information may not be available for release.
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.
ca
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.
Te
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LUMENOLOGY, TAOS, the TAOS logo, and Texas Advanced Optoelectronic Solutions are registered trademarks of Texas Advanced
Optoelectronic Solutions Incorporated.
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19
TSL2550
AMBIENT LIGHT SENSOR
WITH SMBus INTERFACE
Te
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am
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TAOS029L − OCTOBER 2007
Copyright E 2007, TAOS Inc.
20
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