TCS3471

COLOR LIGHT-TO-DIGITAL CONVERTER

TAOS115 − MARCH 2011

2

r

r

Copyright

E 2011, TAOS Inc.

The LUMENOLOGY

r Company

www.taosinc.com

Functional Block Diagram

SDA

INT

SCL

Wait Control

Clear ADC

Upper Limit

Lower Limit

Interrupt

GND

Red ADC

Green ADC

Blue ADC

Clear Data

Red Data

Green Data

Blue Data

RGBC Control

Blue

Green

Red

Clear

Detailed Description

The TCS3471 light-to-digital device contains a 4

× 4 photodiode array, integrating amplifiers, ADCs,

× 4 photodiode array

is composed of red-filtered, green-filtered, blue-filtered, and clear photodiodes — four of each type. Four

integrating ADCs simultaneously convert the amplified photodiode currents to a digital value providing up to 16

bits of resolution. Upon completion of the conversion cycle, the conversion result is transferred to the data

registers. The transfers are double-buffered to ensure that the integrity of the data is maintained.

connection to a microcontroller or embedded controller.

The TCS3471 provides a separate pin for level-style interrupts. When interrupts are enabled and a pre-set value

is exceeded, the interrupt pin is asserted and remains asserted until cleared by the controlling firmware. The

interrupt feature simplifies and improves system efficiency by eliminating the need to poll a sensor for a light

intensity value. An interrupt is generated when the value of an RGBC conversion exceeds either an upper or

lower threshold. In addition, a programmable interrupt persistence feature allows the user to determine how

many consecutive exceeded thresholds are necessary to trigger an interrupt.

Terminal Functions

TERMINAL

TYPE

DESCRIPTION

NAME

NO.

TYPE

DESCRIPTION

GND

3

Power supply ground. All voltages are referenced to GND.

INT

5

O

Interrupt — open drain.

NC

4

Do not connect

SCL

2

I

SDA

6

I/O

1

Supply voltage.