TCS3472 Datasheet

TCS3472
Datasheet - Apr. 2013 - V1.0
Color Light-to-digital Converter with IR Filter
General Description
The TCS3472 device provides a digital return of red, green, blue
(RGB), and clear light sensing values. An IR blocking filter,
integrated on-chip and localized to the color sensing
photodiodes, minimizes the IR spectral component of the
incoming light and allows color measurements to be made
accurately. The high sensitivity, wide dynamic range, and IR
blocking filter make the TCS3472 an ideal color sensor solution
for use under varying lighting conditions and through
attenuating materials.
The TCS3472 color sensor has a wide range of applications
including RGB LED backlight control, solid-state lighting,
health/fitness products, industrial process controls and medical
diagnostic equipment. In addition, the IR blocking filter enables
the TCS3472 to perform ambient light sensing (ALS). Ambient
light sensing is widely used in display-based products such as
cell phones, notebooks, and TVs to sense the lighting
environment and enable automatic display brightness for
optimal viewing and power savings. The TCS3472, itself, can
enter a lower-power wait state between light sensing
measurements to further reduce the average power
consumption.
Figure TCS3472 – 1:
Key Benefits and Features
Benefits
Features
Enables accurate color and light sensing
measurements under varying lighting
conditions by minimizing IR and UV spectral
component effects.
Red, Green, Blue (RGB), and Clear Light
Sensing with IR Blocking Filter
• Programmable Analog Gain and Integration Time
• 3,800,000:1 Dynamic Range
• Very High Sensitivity — Ideally Suited for Operation
Behind Dark Glass
Programmable interrupt pin enables level-style
interrupts when pre-set values are exceeded,
thus reducing companion micro-processor
overhead.
Maskable Interrupt
• Programmable Upper and Lower Thresholds with
Persistence Filter
Enabling a low-power wait-state between RGBC
measurements to reduce average power
consumption.
Power Management
• Low Power — 2.5-μA Sleep State
• 65-μA Wait State with Programmable Wait State Time
from 2.4 ms to > 7 Seconds
Datasheet - Apr. 2013 - V1.0
TCS3472 – 1
Benefits
Features
Digital interfaces are less susceptible to noise.
I²C Fast Mode Compatible Interface
• Data Rates up to 400 kbit/s
• Input Voltage Levels Compatible with VDD or 1.8 VBUS
Backward compatibility enables
interchangeability and re-usability in systems.
Register Set and Pin Compatible with the
TCS3x71 Series
Reduces PCB space requirements while
simplifying designs.
Small 2 mm 2.4 mm Dual Flat No-Lead
(FN) Package
Applications
The applications of TCS3472 include:
•
•
•
•
•
RGB LED Backlight Control
Light Color Temperature Measurement
Ambient Light Sensing for Display Backlight Control
Fluid and Gas Analysis
Product Color Verification and Sorting
End Products and Market Segments
•
•
•
•
•
TVs, Mobile Handsets, Tablets, Computers, and Monitors
Consumer and Commercial Printing
Medical and Health Fitness
Solid State Lighting (SSL) and Digital Signage
Industrial Automation
Figure TCS3472 – 2:
Functional Block Diagram
TCS3472 – 2
Datasheet - Apr. 2013 - V1.0
Detailed Description
The TCS3472 light-to-digital converter contains a 3 × 4
photodiode array, four analog-to-digital converters (ADC) that
integrate the photodiode current, data registers, a state
machine, and an I²C interface. The 3 × 4 photodiode array is
composed of red-filtered, green-filtered, blue-filtered, and
clear (unfiltered) photodiodes. In addition, the photodiodes are
coated with an IR-blocking filter. The four integrating ADCs
simultaneously convert the amplified photodiode currents to a
16-bit digital value. Upon completion of a conversion cycle, the
results are transferred to the data registers, which are
double-buffered to ensure the integrity of the data. All of the
internal timing, as well as the low-power wait state, is controlled
by the state machine.
Communication of the TCS3472 data is accomplished over a
fast, up to 400 kHz, two-wire I²C serial bus. The industry
standard I²C bus facilitates easy, direct connection to
microcontrollers and embedded processors.
In addition to the I²C bus, the TCS3472 provides a separate
interrupt signal output. When interrupts are enabled, and
user-defined thresholds are exceeded, the active-low interrupt
is asserted and remains asserted until it is cleared by the
controller. This interrupt feature simplifies and improves the
efficiency of the system software by eliminating the need to
poll the TCS3472. The user can define the upper and lower
interrupt thresholds and apply an interrupt persistence filter.
The interrupt persistence filter allows the user to define the
number of consecutive out-of-threshold events necessary
before generating an interrupt. The interrupt output is
open-drain, so it can be wire-ORed with other devices.
Datasheet - Apr. 2013 - V1.0
TCS3472 – 3
The TCS3472 pin assignments are described below.
Pin Assignment
Figure TCS3472 – 3:
Pin Diagram
Package FN Dual Flat No-Lead (Top
View): Package drawing is not to scale.
VDD
1
6
SDA
SCL
2
5
INT
GND
3
4
NC
Figure TCS3472 – 4:
Pin Description
Pin Number
Pin Name
1
VDD
2
SCL
3
GND
4
NC
Output
No connect — do not connect.
5
INT
Output
Interrupt — open drain (active low).
6
SDA
Input/Output
TCS3472 – 4
Pin Type
Description
Supply voltage.
Input
I²C serial clock input terminal – clock signal for I²C serial data.
Power supply ground. All voltages are referenced to GND.
I²C serial data I/O terminal — serial data I/O for I²C.
Datasheet - Apr. 2013 - V1.0
Ordering Information
Figure TCS3472 – 5:
Ordering Information
Device
Address
Package-Leads
Interface Description
Ordering Number
TCS34721†
0x39
FN−6
I²C VBUS = VDD Interface
TCS34721FN
TCS34723†
0x39
FN−6
I²C VBUS = 1.8 V Interface
TCS34723FN
TCS34725
0x29
FN−6
I²C VBUS = VDD Interface
TCS34725FN
TCS34727
0x29
FN−6
I²C VBUS = 1.8 V Interface
TCS34727FN
†Contact ams for availability.
Notes:
1. All products are RoHS compliant and ams green.
2. Buy our products or get free samples online at www.ams.com/ICdirect
3. Technical Support is available at www.ams.com/Technical-Support
4. For further information and requests, email us at [email protected]
5. (or) find your local distributor at www.ams.com/distributor
Absolute Maximum Ratings
Stresses beyond those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device. These are
stress ratings only. 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.
Figure TCS3472 – 6:
Absolute Maximum Ratings over Operating Free-air Temperature Range (unless otherwise noted)
Parameter
Min
Supply voltage, VDD
Max
Units
Comments
3.8
V
All voltages are with respect to GND
Input terminal voltage
−0.5
3.8
V
Output terminal voltage
−0.5
3.8
V
Output terminal current
−1
20
mA
Storage temperature range, Tstg
−40
85
ºC
2000
V
ESD tolerance, human body model
Datasheet - Apr. 2013 - V1.0
TCS3472 – 5
All limits are guaranteed. The parameters with min and max
values are guaranteed with production tests or SQC (Statistical
Quality Control) methods.
Electrical Characteristics
Figure TCS3472 – 7:
Recommended Operating Conditions
Symbol
VDD
TA
Parameter
Conditions
Min
Typ
Max
TCS34721 & TCS34725 (I²C VBUS = VDD)
2.7
3
3.6
TCS34723 & TCS34727 (I²C VBUS = 1.8 V)
2.7
3
3.3
Supply voltage
Units
V
Operating free - air
temperature
-30
70
ºC
Figure TCS3472 – 8:
Operating Characteristics, VDD = 3 V, TA = 25ºC (unless otherwise noted)
Symbol
IDD
VOL
ILEAK
VIH
VIL
TCS3472 – 6
Parameter
Supply current
Conditions
Min
Typ
Max
Active
235
330
Wait state
65
Sleep state - no I²C activity
2.5
Units
μA
10
3 mA sink current
0
0.4
6 mA sink current
0
0.6
Leakage current, SDA, SCL,
INT pins
-5
5
Leakage current, LDR pin
-5
INT SDA output low voltage
V
μA
TCS34721 & TCS34725
0.7 VDD
TCS34723 & TCS34727
1.25
5
SCL SDA input high voltage
V
TCS34721 & TCS34725
0.3 VDD
TCS34723 & TCS34727
0.54
SCL SDA input low voltage
V
Datasheet - Apr. 2013 - V1.0
Figure TCS3472 – 9:
Optical Characteristics, VDD=3 V, TA = 25ºC, AGAIN = 16, ATIME = 0xF6(unless otherwise noted) (Note 1)
Parameter
Red
Channel
Test
Conditions
Blue
Channel
Clear Channel
Unit
Min
Max
Min
Max
Min
Max
Min
Typ
Max
0%
15%
10%
42%
65%
88%
11.0
13.8
16.6
λD = 465 nm
Note 2
Re
Irradiance
responsivity
Green
Channel
λD = 525 nm
Note 3
4%
25%
60%
85%
10%
45%
13.2
16.6
20.0
λD = 615 nm
Note 4
80%
110%
0%
14%
5%
24%
15.6
19.5
23.4
counts
/μW
/cm2
Notes:
1. The percentage shown represents the ratio of the respective red, green, or blue channel value to the clear channel value.
2. The 465 nm input irradiance is supplied by an InGaN light-emitting diode with the following characteristics: dominant
wavelength λ D = 465 nm, spectral halfwidth Δλ½ = 22 nm.
3. The 525 nm input irradiance is supplied by an InGaN light-emitting diode with the following characteristics: dominant
wavelength λ D = 525 nm, spectral halfwidth Δλ½ = 35 nm.
4. The 615 nm input irradiance is supplied by a AlInGaP light-emitting diode with the following characteristics: dominant
wavelength λ D = 615 nm, spectral halfwidth Δλ½ = 15 nm.
Figure TCS3472 – 10:
RGBC Characteristics, VDD = 3 V, TA = 25ºC, AGAIN = 16, AEN = 1 (unless otherwise noted)
Parameter
Conditions
Min
Typ
Max
Units
Dark ADC count value
Ee = 0, AGAIN = 60×, ATIME =
0xD6 (100 ms)
0
1
5
counts
ADC integration time step size
ATIME = 0xFF
2.27
2.4
2.56
ms
ADC number of integration steps
(see Note below)
1
256
steps
ADC counts per step (see Note
below)
0
1024
counts
0
65535
counts
ADC count value (see Note below)
Gain scaling, relative to 1X gain
setting
ATIME = 0xC0 (153.6 ms)
4X
3.8
4
4.2
16X
15
16
16.8
60X
58
60
63
X
Note: Parameter ensured by design and is not tested.
Datasheet - Apr. 2013 - V1.0
TCS3472 – 7
Figure TCS3472 – 11:
Wait Characteristics, VDD = 3 V, TA = 25ºC, WEN = 1 (unless otherwise noted)
Parameter
Wait step size
Conditions
WTIME = 0xFF
Wait number of integration steps
(see Note below)
Channel
Min
Typ
Max
Units
2.27
2.4
2.56
ms
256
steps
1
Note: Parameter ensured by design and is not tested.
TCS3472 – 8
Datasheet - Apr. 2013 - V1.0
The timing characteristics of TCS3472 are given below.
Timing Characteristics
Figure TCS3472 – 12:
AC Electrical Characteristics, VDD = 3 V, TA = 25ºC (unless otherwise noted)
Parameter†
Description
Min
Typ
Max
Units
400
kHz
f(SCL)
Clock frequency (I²C only)
t(BUF)
Bus free time between start and stop condition
1.3
μs
t(HDSTA)
Hold time after (repeated) start condition. After
this period, the first clock is generated.
0.6
μs
t(SUSTA)
Repeated start condition setup time
0.6
μs
t(SUSTO)
Stop condition setup time
0.6
μs
t(HDDAT)
Data hold time
0
t(SUDAT)
Data setup time
100
ns
t(LOW)
SCL clock low period
1.3
μs
t(HIGH)
SCL clock high period
0.6
μs
0
0.9
μs
tF
Clock/data fall time
300
ns
tR
Clock/data rise time
300
ns
Ci
Input pin capacitance
10
pF
† Specified by design and characterization; not production tested.
Timing Diagrams
Figure TCS3472 – 13:
Parameter Measurement Information
Datasheet - Apr. 2013 - V1.0
TCS3472 – 9
Typical Operating Characteristics
Relative Responsivity
Figure TCS3472 – 14:
Photodiode Spectral Responsivity RGBC
λ - Wavelength - nm
Normalized Responsivity
Figure TCS3472 – 15:
Normalized Responsivity vs. Angular Displacement
θ - Angular Displacement - º
TCS3472 – 10
Datasheet - Apr. 2013 - V1.0
IDD Normalized @ 3V, 25ºC
Figure TCS3472 – 16:
Normalized IDD vs. VDD and Temperature
VDD – V
Temperature Coefficient - ppm/ºC
Figure TCS3472 – 17:
Responsivity Temperature Coefficient
λ - Wavelength - nm
Datasheet - Apr. 2013 - V1.0
TCS3472 – 11
Principles of Operation
System States
An internal state machine provides system control of the RGBC
and power management features of the device. At power up,
an internal power-on-reset initializes the device and puts it in
a low-power Sleep state.
When a start condition is detected on the I²C bus, the device
transitions to the Idle state where it checks the Enable Register
(0x00) PON bit. If PON is disabled, the device will return to the
Sleep state to save power. Otherwise, the device will remain in
the Idle state until the RGBC function is enabled (AEN). Once
enabled, the device will execute the Wait and RGBC states in
sequence as indicated in Figure TCS3472 - 17. Upon completion
and return to Idle, the device will automatically begin a new
Wait-RGBC cycle as long as PON and AEN remain enabled.
Figure TCS3472 – 18:
Simplified State Diagram
TCS3472 – 12
Datasheet - Apr. 2013 - V1.0
RGBC Operation
The RGBC engine contains RGBC gain control (AGAIN) and four
integrating analog-to-digital converters (ADC) for the RGBC
photodiodes. The RGBC integration time (ATIME) impacts both
the resolution and the sensitivity of the RGBC reading.
Integration of all four channels occurs simultaneously and upon
completion of the conversion cycle, the results are transferred
to the color data registers. This data is also referred to as channel
count.
The transfers are double-buffered to ensure that invalid data is
not read during the transfer. After the transfer, the device
automatically moves to the next state in accordance with the
configured state machine.
Figure TCS3472 – 19:
RGBC Operation
Note: In this document, the nomenclature uses the bit field name in italics followed by the register address and bit number to
allow the user to easily identify the register and bit that controls the function. For example, the power on (PON) is in
register 0x00, bit 0. This is represented as PON (r0x00:b0).
The registers for programming the integration and wait times
are a 2’s compliment values. The actual time can be calculated
as follows:
ATIME = 256 − Integration Time / 2.4 ms
Inversely, the time can be calculated from the register value as
follows:
Integration Time = 2.4 ms × (256 − ATIME)
For example, if a 100-ms integration time is needed, the device
needs to be programmed to:
256 − (100 / 2.4) = 256 − 42 = 214 = 0xD6
Conversely, the programmed value of 0xC0 would correspond
to:
(256 − 0xC0) × 2.4 = 64 × 2.4 = 154 ms.
Datasheet - Apr. 2013 - V1.0
TCS3472 – 13
Interrupts
The interrupt feature simplifies and improves system efficiency
by eliminating the need to poll the sensor for light intensity
values outside of a user-defined range. While the interrupt
function is always enabled and its status is available in the
status register (0x13), the output of the interrupt state can be
enabled using the RGBC interrupt enable (AIEN) field in the
enable register (0x00).
Two 16-bit interrupt threshold registers allow the user to set
limits below and above a desired light level. An interrupt can
be generated when the Clear data (CDATA) is less than the Clear
interrupt low threshold (AILTx) or is greater than the Clear
interrupt high threshold (AIHTx).
It is important to note that the thresholds are evaluated in
sequence, first the low threshold, then the high threshold. As a
result, if the low threshold is set above the high threshold, the
high threshold is ignored and only the low threshold is
evaluated.
To further control when an interrupt occurs, the device provides
a persistence filter. The persistence filter allows the user to
specify the number of consecutive out-of-range Clear
occurrences before an interrupt is generated. The persistence
filter register (0x0C) allows the user to set the Clear persistence
filter (APERS) value. See the persistence filter register for details
on the persistence filter value. Once the persistence filter
generates an interrupt, it will continue until a special function
interrupt clear command is received (see command register).
Figure TCS3472 – 20:
Programmable Interrupt
TCS3472 – 14
Datasheet - Apr. 2013 - V1.0
System Timing
The system state machine shown in Figure TCS3472 - 18
provides an overview of the states and state transitions that
provide system control of the device. This section highlights the
programmable features, which affect the state machine cycle
time, and provides details to determine system level timing.
When the power management feature is enabled (WEN), the
state machine will transition to the Wait state. The wait time is
determined by WLONG, which extends normal operation by
12× when asserted, and WTIME. The formula to determine the
wait time is given in the box associated with the Wait state in
Figure TCS3472 - 21.
When the RGBC feature is enabled (AEN), the state machine will
transition through the RGBC Init and RGBC ADC states. The
RGBC Init state takes 2.4 ms, while the RGBC ADC time is
dependent on the integration time (ATIME). The formula to
determine RGBC ADC time is given in the associated box in
Figure TCS3472 - 21. If an interrupt is generated as a result of
the RGBC cycle, it will be asserted at the end of the RGBC ADC.
Figure TCS3472 – 21:
Detailed State Diagram
Notes:
1. There is a 2.4 ms warm-up delay if PON is enabled. If PON is not enabled, the device will return to the Sleep state as shown.
2. PON, WEN, and AEN are fields in the Enable register (0x00).
Datasheet - Apr. 2013 - V1.0
TCS3472 – 15
Power Management
Power consumption can be managed with the Wait state,
because the Wait state typically consumes only 65 μA of IDD
current. An example of the power management feature is given
below. With the assumptions provided in the example, average
IDD is estimated to be 152 μA.
Figure TCS3472 – 22:
Power Management
System State
Machine State
Programmable
Parameter
Programmed
Value
WTIME
0xEE
WLONG
0
Wait
RGBC Init
RGBC ADC
ATIME
0xEE
Duration
Typical
Current
43.2 ms
0.065 mA
2.40 ms
0.235 mA
43.2 ms
0.235 mA
Average I DD Current = ((43.2 × 0.065) + (43.2 × 0.235) + (2.40 ×
0.235)) / 89 ≈ 152 μA
Keeping with the same programmed values as the example,
Figure TCS3472 - 23 shows how the average IDD current is
affected by the Wait state time, which is determined by WEN,
WTIME, and WLONG. Note that the worst-case current occurs
when the Wait state is not enabled.
Figure TCS3472 – 23:
Average IDD Current
WEN
WTIME
WLONG
WAIT State
Average IDD Current
0
n/a
n/a
0 ms
291 μA
1
0xFF
0
2.40 ms
280 μA
1
0XEE
0
43.2 ms
152 μA
1
0x00
0
614 ms
82 μA
1
0x00
1
7.37 s
67 μA
TCS3472 – 16
Datasheet - Apr. 2013 - V1.0
Interface and control are accomplished through an I²C serial
compatible interface (standard or fast mode) to a set of registers
that provide access to device control functions and output data.
The devices support the 7-bit I²C addressing protocol.
I²C Protocol
The I²C standard provides for three types of bus transaction:
read, write, and a combined protocol (Figure TCS3472 - 24).
During a write operation, the first byte written is a command
byte followed by data. In a combined protocol, the first byte
written is the command byte followed by reading a series of
bytes. If a read command is issued, the register address from
the previous command will be used for data access. Likewise, if
the MSB of the command is not set, the device will write a series
of bytes at the address stored in the last valid command with a
register address. The command byte contains either control
information or a 5-bit register address. The control commands
can also be used to clear interrupts.
The I²C bus protocol was developed by Philips (now NXP). For
a complete description of the I²C protocol, please review the
NXP I²C design specification at
http://www.I2C−bus.org/references/.
Figure TCS3472 – 24:
I²C Protocols
A
N
P
R
S
Acknowledge (0)
Not Acknowledged (1)
Stop Condition
Read (1)
Start Condition
Datasheet - Apr. 2013 - V1.0
Sr
W
Repeated Start Condition
Write (0)
Continuation of Protocol
Master - to - Slave
Slave - to - Master
TCS3472 – 17
The TCS3472 is controlled and monitored by data registers and
a command register accessed through the serial interface.
These registers provide for a variety of control functions and
can be read to determine results of the ADC conversions. The
register set is summarized in Figure TCS3472 - 25.
Register Description
Figure TCS3472 – 25:
Register Set
Address
−−
Register Name
COMMAND
R/W
W
Register Function
Reset Value
Specifies register address
0x00
0x00
ENABLE
R/W
Enables states and interrupts
0x00
0x01
ATIME
R/W
RGBC time
0xFF
0x03
WTIME
R/W
Wait time
0xFF
0x04
AILTL
R/W
Clear interrupt low threshold low byte
0x00
0x05
AILTH
R/W
Clear interrupt low threshold high byte
0x00
0x06
AIHTL
R/W
Clear interrupt high threshold low byte
0x00
0x07
AIHTH
R/W
Clear interrupt high threshold high byte
0x00
0x0C
PERS
R/W
Interrupt persistence filter
0x00
0x0D
CONFIG
R/W
Configuration
0x00
0x0F
CONTROL
R/W
Control
0x00
0x12
ID
R
Device ID
0x13
STATUS
R
Device status
0x00
0x14
CDATAL
R
Clear data low byte
0x00
0x15
CDATAH
R
Clear data high byte
0x00
0x16
RDATAL
R
Red data low byte
0x00
0x17
RDATAH
R
Red data high byte
0x00
0x18
GDATAL
R
Green data low byte
0x00
0x19
GDATAH
R
Green data high byte
0x00
0x1A
BDATAL
R
Blue data low byte
0x00
0x1B
BDATAH
R
Blue data high byte
0x00
ID
The mechanics of accessing a specific register depends on the
specific protocol used. See the section on I²C protocols on the
previous pages. In general, the COMMAND register is written
first to specify the specific control-status-data register for
subsequent read/write operations.
TCS3472 – 18
Datasheet - Apr. 2013 - V1.0
The COMMAND registers specifies the address of the target
register for future write and read operations.
Command Register
7
6
CMD
5
4
3
2
TYPE
Fields
Bits
CMD
7
1
0
ADDR/SF
Description
Select Command Register. Must write as 1 when addressing COMMAND register.
Selects type of transaction to follow in subsequent data transfers:
FIELD VALUE
TYPE
6:5
INTEGRATION TIME
00
Repeated byte protocol transaction
01
Auto-increment protocol transaction
10
Reserved — Do not use
11
Special function — See description below
Byte protocol will repeatedly read the same register with each data access. Block
protocol will provide auto-increment function to read successive bytes.
Address field/special function field. Depending on the transaction type, see above,
this field either specifies a special function command or selects the specific
control-status-data register for subsequent read and write transactions. The field
values listed below only apply to special function commands:
FIELD VALUE
ADDR/SF
READ VALUE
4:0
00110
Clear channel interrupt clear
Other
Reserved — Do not write
The Clear channel interrupt clear special function clears any pending interrupt and
is self-clearing.
Datasheet - Apr. 2013 - V1.0
TCS3472 – 19
The ENABLE register is used primarily to power the TCS3472
device ON and OFF, and enable functions and interrupts as
shown below.
Enable Register (0x00)
7
6
5
Reserved
4
3
2
1
0
AIEN
WEN
Reserved
AEN
PON
Fields
Bits
Description
Reserved
7:5
AIEN
4
RGBC interrupt enable. When asserted, permits RGBC interrupts to be
generated.
WEN
3
Wait enable. This bit activates the wait feature. Writing a 1 activates the wait
timer. Writing a 0 disables the wait timer.
Reserved
2
Reserved. Write as 0.
AEN
1
RGBC enable. This bit actives the two-channel ADC. Writing a 1 activates the
RGBC. Writing a 0 disables the RGBC.
PON
(Notes 1, 2)
0
Power ON. This bit activates the internal oscillator to permit the timers and
ADC channels to operate. Writing a 1 activates the oscillator. Writing a 0
disables the oscillator.
Reserved. Write as 0.
Notes:
1. See Power Management section for more information.
2. A minimum interval of 2.4 ms must pass after PON is asserted before an RGBC can be initiated.
TCS3472 – 20
Datasheet - Apr. 2013 - V1.0
The RGBC timing register controls the internal integration time
of the RGBC clear and IR channel ADCs in 2.4-ms increments.
Max RGBC Count = (256 − ATIME) × 1024 up to a maximum of
65535.
RGBC Timing Register (0x01)
Fields
ATIME
Bits
Description
VALUE
INTEG_CYCLES
TIME
MAX COUNT
0xFF
1
2.4 ms
1024
0xF6
10
24 ms
10240
0xD5
42
101 ms
43008
0xC0
64
154 ms
65535
0x00
256
700 ms
65535
7:0
Wait time is set 2.4 ms increments unless the WLONG bit is
asserted, in which case the wait times are 12× longer. WTIME is
programmed as a 2’s complement number.
Wait Time Register (0x03)
Fields
WTIME
Bits
Description
REGISTER VALUE
WAIT TIME
TIME (WLONG= 0)
TIME (WLONG= 1)
0xFF
1
2.4 ms
0.029 sec
0xAB
85
204 ms
2.45 sec
0x00
256
614 ms
7.4 sec
7:0
The RGBC interrupt threshold registers provides the values to
be used as the high and low trigger points for the comparison
function for interrupt generation. If the value generated by the
clear channel crosses below the lower threshold specified, or
above the higher threshold, an interrupt is asserted on the
interrupt pin.
RGBC Interrupt Threshold Registers
(0x04 − 0x07)
Register
Address
Bits
AILTL
0x04
7:0
RGBC clear channel low threshold lower byte
AILTH
0x05
7:0
RGBC clear channel low threshold upper byte
AIHTL
0x06
7:0
RGBC clear channel high threshold lower byte
AIHTH
0x07
7:0
RGBC clear channel high threshold upper byte
Datasheet - Apr. 2013 - V1.0
Description
TCS3472 – 21
The persistence register controls the filtering interrupt
capabilities of the device. Configurable filtering is provided to
allow interrupts to be generated after each integration cycle or
if the integration has produced a result that is outside of the
values specified by the threshold register for some specified
amount of time.
Persistence Register (0x0C)
7
6
5
4
3
2
Reserved
Field
Bits
PPERS
7:4
1
0
APERS
Description
Reserved
Interrupt persistence. Controls rate of interrupt to the host processor.
APERS
TCS3472 – 22
FIELD VALUE
MEANING
INTERRUPT PERSISTENCE FUNCTION
0000
Every
0001
1
1 clear channel value outside of threshold range
0010
2
2 clear channel consecutive values out of range
0011
3
3 clear channel consecutive values out of range
0100
5
5 clear channel consecutive values out of range
0101
10
10 clear channel consecutive values out of range
0110
15
15 clear channel consecutive values out of range
0111
20
20 clear channel consecutive values out of range
1000
25
25 clear channel consecutive values out of range
1001
30
30 clear channel consecutive values out of range
1010
35
35 clear channel consecutive values out of range
1011
40
40 clear channel consecutive values out of range
1100
45
45 clear channel consecutive values out of range
1101
50
50 clear channel consecutive values out of range
1110
55
55 clear channel consecutive values out of range
1111
60
60 clear channel consecutive values out of range
Every RGBC cycle generates an interrupt
3:0
Datasheet - Apr. 2013 - V1.0
Configuration Register (0x0D)
7
6
The configuration register sets the wait long time
5
4
3
2
Reserved
1
0
WLONG
Reserved
Fields
Bits
Description
Reserved
7:2
WLONG
1
Wait Long. When asserted, the wait cycles are increased by a factor 12× from
that programmed in the WTIME register.
Reserved
0
Reserved. Write as 0.
Reserved. Write as 0.
The Control register provides eight bits of miscellaneous
control to the analog block. These bits typically control
functions such as gain settings and/or diode selection.
Control Register (0x0F)
7
6
5
4
3
2
1
Reserved
Fields
Bits
Reserved
7:2
0
AGAIN
Description
Reserved. Write as 0.
RGBC Gain Control.
AGAIN
FIELD VALUE
RGBC GAIN VALUE
00
1X gain
01
4X gain
10
16X gain
11
60X gain
1:0
Datasheet - Apr. 2013 - V1.0
TCS3472 – 23
The ID Register provides the value for the part number. The ID
register is a read-only register.
ID Register (0x12)
7
6
5
4
3
2
1
0
ID
Field
Bits
ID
7:0
Description
0x44 = TCS34721 and TCS34725
Part number identification 0x19
0x4D = TCS34723 and TCS34727
The Status Register provides the internal status of the device.
This register is read only.
Status Register (0x13)
7
6
5
Reserved
Field
Bits
Reserved
7:5
AINT
4
Reserved
3:1
AVALID
0
TCS3472 – 24
4
AINT
3
2
Reserved
1
0
AVALID
Description
Reserved.
RGBC clear channel Interrupt.
Reserved.
RGBC Valid. Indicates that the RGBC channels have completed an integration cycle.
Datasheet - Apr. 2013 - V1.0
RGBC Channel Data Registers (0x14 –
0x1B)
Clear, red, green, and blue data is stored as 16-bit values. To
ensure the data is read correctly, a two-byte read I²C transaction
should be used with a read word protocol bit set in the
command register. With this operation, when the lower byte
register is read, the upper eight bits are stored into a shadow
register, which is read by a subsequent read to the upper byte.
The upper register will read the correct value even if additional
ADC integration cycles end between the reading of the lower
and upper registers.
Register
Address
Bits
CDATA
0x14
7:0
Clear data low byte
CDATAH
0x15
7:0
Clear data high byte
RDATA
0x16
7:0
Red data low byte
RDATAH
0x17
7:0
Red data high byte
GDATA
0x18
7:0
Green data low byte
GDATAH
0x19
7:0
Green data high byte
BDATA
0x1A
7:0
Blue data low byte
BDATAH
0x1B
7:0
Blue data high byte
Datasheet - Apr. 2013 - V1.0
Description
TCS3472 – 25
Application Information: Hardware
PCB Pad Layout
Suggested PCB pad layout guidelines for the Dual Flat No-Lead
(FN) surface mount package are shown in Figure TCS3472 - 26.
Figure TCS3472 – 26:
Suggested FN Package PCB Layout
Pads can be extended further if hand soldering is needed.
Notes:
1. All linear dimensions are in millimeters.
2. This drawing is subject to change without notice.
TCS3472 – 26
Datasheet - Apr. 2013 - V1.0
Package Drawings and Markings
Figure TCS3472 – 27:
Package FN – Dual Flat No-Lead Packaging Configuration
Notes:
1. All linear dimensions are in micrometers. Dimension tolerance is ±20 μm unless otherwise noted.
2. The die is centered within the package within a tolerance of ± 3 mils.
3. Package top surface is molded with an electrically nonconductive clear plastic compound having an index of refraction of 1.55.
4. Contact finish is copper alloy A194 with pre-plated NiPdAu lead finish.
5. This package contains no lead (Pb).
6. This drawing is subject to change without notice.
Datasheet - Apr. 2013 - V1.0
TCS3472 – 27
Mechanical Data
Figure TCS3472 – 28:
Carrier Tape and Reel Information
Notes:
1. All linear dimensions are in millimeters. Dimension tolerance is ± 0.10 mm unless otherwise noted.
2. The dimensions on this drawing are for illustrative purposes only. Dimensions of an actual carrier may vary slightly.
3. Symbols on drawing A0, B 0, and K 0 are defined in ANSI EIA Standard 481-B 2001.
4. Each reel is 178 millimeters in diameter and contains 3500 parts.
5. ams packaging tape and reel conform to the requirements of EIA Standard 481-B.
6. In accordance with EIA standard, device pin 1 is located next to sprocket holes in the tape.
7. This drawing is subject to change without notice.
TCS3472 – 28
Datasheet - Apr. 2013 - V1.0
Soldering and Storage Information
Soldering Information
The FN package has been tested and has demonstrated an
ability to be reflow soldered to a PCB substrate. The process,
equipment, and materials used in these test are detailed below.
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.
Figure TCS3472 – 29:
Solder Reflow Profile
Parameter
Reference
Average temperature gradient in preheating
Device
2.5 ºC/sec
tsoak
2 to 3 minutes
Time above 217 ºC (T1)
t1
Max 60 sec
Time above 230 ºC (T2)
t2
Max 50 sec
Time above Tpeak - 10 ºC (T3)
t3
Max 10 sec
Peak temperature in reflow
Tpeak
260 ºC
Soak time
Temperature gradient in cooling
Max -5 ºC/sec
Figure TCS3472 – 30:
Solder Reflow Profile Graph
Note: Not to scale – for reference only.
Datasheet - Apr. 2013 - V1.0
TCS3472 – 29
Storage 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.
To ensure the package 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 called a moisture barrier bag with silica
gel to protect them from ambient moisture during shipping,
handling, and storage before use.
The Moisture Barrier Bags should be stored under the following
conditions:
• Temperature Range < 40°C
• Relative Humidity < 90%
• Total Time - No longer than 12 months from the date code
on the aluminized envelope if unopened.
Rebaking of the reel will be required if the devices have been
stored unopened for more than 12 months and the Humidity
Indicator Card shows the parts to be out of the allowable
moisture region.
Opened reels should be used within 168 hours if exposed to the
following conditions:
• Temperature Range < 30°C
• Relative Humidity < 60%
If rebaking is required, it should be done at 50°C for 12 hours.
The FN package has been assigned a moisture sensitivity level
of MSL 3.
TCS3472 – 30
Datasheet - Apr. 2013 - V1.0
RoHS Compliant and ams Green
Statement
The term RoHS complaint means that ams products fully comply
with current RoHS directive. Our semiconductor products do
not contain any chemicals for all 6 substance categories,
including the requirement that lead not exceed 0.1% by weight
in homogeneous materials. Where designed to be soldered at
high temperatures, RoHS compliant products are suitable for
use in specified lead-free processes. ams Green means RoHS
compliant and no Sb/Br). ams defines Green that additionally
to RoHS compliance our products are free of Bromine (Br) and
Antimony (Sb) based flame retardants (Br or Sb do not exceed
0.1% by weight in homogeneous material).
Important Information and Disclaimer The information
provided in this statement represents ams knowledge and
belief as of the date that it is provided. ams 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. ams 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. ams
and ams suppliers consider certain information to be
proprietary, and thus CAS numbers and other limited
information may not be available for release.
Datasheet - Apr. 2013 - V1.0
TCS3472 – 31
Copyrights
Copyright © 1997-2013, ams AG, Tobelbaderstrasse 30, 8141
Unterpremstaetten, Austria-Europe. Trademarks Registered ®.
All rights reserved. The material herein may not be reproduced,
adapted, merged, translated, stored, or used without the prior
written consent of the copyright owner.
Disclaimer
Devices sold by ams AG are covered by the warranty and patent
indemnification provisions appearing in its Term of Sale. ams
AG makes no warranty, express, statutory, implied, or by
description regarding the information set forth herein or
regarding the freedom of the described devices from patent
infringement. ams AG reserves the right to change
specifications and prices at any time and without notice.
Therefore, prior to designing this product into a system, it is
necessary to check with ams AG for current information. This
product is intended for use in normal commercial applications.
Applications requiring extended temperature range, unusual
environmental requirements, or high reliability applications,
such as military, medical life-support or life-sustaining
equipment are specifically not recommended without
additional processing by ams AG for each application. For
shipments of less than 100 parts the manufacturing flow might
show deviations from the standard production flow, such as test
flow or test location.
The information furnished here by ams AG is believed to be
correct and accurate. However, ams AG shall not be liable to
recipient or any third party for any damages, including but not
limited to personal injury, property damage, loss of profits, loss
of use, interruption of business or indirect, special, incidental
or consequential damages, of any kind, in connection with or
arising out of the furnishing, performance or use of the
technical data herein. No obligation or liability to recipient or
any third party shall arise or flow out of ams AG rendering of
technical or other services.
TCS3472 – 32
Datasheet - Apr. 2013 - V1.0