TCS3404, TCS3414
DIGITAL COLOR SENSORS
TAOS137A − APRIL 2011
A synchronization input (SYNC) provides precise external control of sensor integration allowing the internal
conversion cycles to be synchronized to a pulsed light source. Furthermore, the synchronization feature
supports the following advanced modes of operation to maximize flexibility across a broad range of hardware
systems: (1) sync for one internal-time cycle, and (2) accumulate for specified number of pulses. The device
also supports free-running and serial-bus-controlled integration modes if precise coupling between the sensor
and light source is not required.
Four parallel analog-to-digital converters (ADC) transform the photodiode currents to an SMBus (TCS3404) or
2
I C (TCS3414) digital output that, in turn, can be input to a microprocessor. The RGB values can be read in a
single read cycle to minimize the number of read command protocols defined in the communication interface.
The slave address for this device is 39h (0111001b). A single SMB-Alert style interrupt (TCS3404) as well as
a single traditional level-style interrupt (TCS3414) can be dynamically configured for any one of the four
channels including a corresponding high/low threshold setting. The interrupt will remain asserted until the
firmware clears the interrupt.
The TCS3404/14 devices can help (1) automatically adjust the display brightness of a backlight to extend
battery, increase lamp life, and provide optimum viewing in diverse lighting conditions, (2) white-color balance
display panel and/or captured images in diverse lighting conditions, and (3) manage RGB LED backlighting to
maintain color consistency over a long period of time.
These devices are also ideal in controlling keyboard illumination in low ambient light conditions. Chromaticity
coordinates (x,y) can be used to derive color temperature for the purpose of white-color balancing of displays
and/or captured images. Illuminance, in lux, can be used to approximate the human eye response of ambient
light and to manage exposure control in digital cameras. The TCS3404/14 devices are ideal in notebook/tablet
PCs, LCD monitors, flat-panel televisions, cell phones, and digital cameras. Additional applications include
street light control, security lighting, sunlight harvesting, and automotive instrumentation clusters.
Functional Block Diagram
IR-Blocking Filter
(CS Package Only)
Integrating
A/D Converter
Red Channel
Integrating
A/D Converter
Green Channel
Integrating
A/D Converter
Blue Channel
Integrating
A/D Converter
Clear Channel
Command
Register
4-Parallel ADC
Registers
V
DD
Interrupt
INT
SCL
SDA
Synchronization
Two-Wire Serial Interface
SYNC
Copyright E 2011, TAOS Inc.
The LUMENOLOGY r Company
r
r
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www.taosinc.com
TAOS [ TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS ]
