TCS3103, TCS3104

LIGHT-TO-VOLTAGE COLOR SENSOR

TAOS108B − JULY 2010

6

r

r

Copyright

E 2010, TAOS Inc.

The LUMENOLOGY

r Company

www.taosinc.com

APPLICATION INFORMATION

Power Supply Considerations

short leads (ideally, a surface mount ceramic type) as close as possible to the device package.

Output Interface

Although the output of the device can be connected to a comparator for simple threshold measurements, or to

another amplifier stage, most applications will require that the three channels be connected to analog-to-digital

converters (ADCs) so that the light and color information can be processed by a microcontroller, computer, or

other device. In many cases, the outputs can be directly connected to the ADC inputs. In some cases, for

example if the light is modulated, it may be desirable to insert active or passive low-pass filters on the channels

prior to the ADC, to smooth out the modulation ripple that would otherwise result in noisy measurements. The

cutoff frequency of the filters would, of course, depend upon the modulation frequency of the incoming light. With

a pulse-width modulated (PWM) input light signal, it may be possible to synchronize the ADC sampling with the

on-time of the PWM signal. In this case, a low-pass filter would not be required because the device output would

be sampled only during the on time of the input light source. A recommendation for minimum pulse width

would be 3

Device Power Up

The TCS310x should use the following power up sequence: A stable ground reference from the system should

pin is floating or without a ground reference. Afterward, the MFP pin may be biased or driven. The MFP pin must

always have a valid logic reference level. The pin may be biased or driven to a logical high or logical low level.

PCB Pad Layout

Suggested PCB pad layout guidelines for the Dual Flat No-Lead (FN) surface mount package are shown in

Figure 6.

0.40

2.90

0.40

1.30

1.70

0.65

1.30

0.65

NOTES: A. All linear dimensions are in millimeters.

B. This drawing is subject to change without notice.

Figure 6. Suggested FN Package PCB Layout