TCS3404, TCS3414

DIGITAL COLOR SENSORS

TAOS137A − APRIL 2011

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Copyright

E 2011, TAOS Inc.

The LUMENOLOGY

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www.taosinc.com

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

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

Two-Wire Serial Interface

Interrupt

SDA

Blue Channel

Clear Channel

Command

Register

4-Parallel ADC

Registers

INT

SCL

Green Channel

Red Channel

Integrating

A/D Converter

Integrating

A/D Converter

Integrating

A/D Converter

Integrating

A/D Converter

Synchronization

SYNC

IR-Blocking Filter

(CS Package Only)