Data Sheet

ManualsBrandsGravitech ManualsMisc. IR & Light SensorsI2C 16-BIT Color Level Sensor RGBC

TCS3404, TCS3414

DIGITAL COLOR SENSORS

TAOS137A − APRIL 2011

The LUMENOLOGY r Company

www.taosinc.com

Gain Register (07h)

The Gain register provides a common gain control adjustment for all four parallel ADC output channels. Two

gain bits [5:4] in the Gain Register allow the relative gain to be adjusted from 1× to 64× in 4× increments. The

advantage of the gain adjust is to extend the dynamic range of the light input up to a factor of 64× before analog

or digital saturation occurs. If analog saturation has occurred, lowering the gain sensitivity will likely prevent

analog saturation especially when the integration time is relatively short. For longer integration times, the 16-bit

output could be in digital saturation (64K). If lowering the gain to 1× does not prevent digital saturation from

occurring, the use of PRESCALER can be useful.

The PRESCALER is 3 bits [2:0] in the gain register that divides down the output count (i.e. shifts the LSB of the

count value to the right). The PRESCALER adjustment range is divide by 1 to 64 in multiples of 2.

The most sensitive gain setting of the device would be when GAIN is set to 11b (64×), and PRESCALER is set

to 000b (divide by 1). The least sensitive part setting would be GAIN 00 (1×) and PRESCALER 110 (divide by

64). If the part continues to be in digital saturation at the least sensitive setting, the integration time can be

lowered (see Timing Register section).

Table 9. Gain Register

67542310

0000 0000Reset Value:

GAIN

Resv GAIN Resv

07h

PRESCALERResv

FIELD BITS DESCRIPTION

Resv 7:6 Reserved. Write as 0.

Analog Gain Control. This field switches the common analog gain of the four ADC channels. Four gain

modes are provided:

FIELD VALUE GAIN

GAIN 5:4

00 1×

GAIN

5:4

01 4×

10 16×

11 64×

Resv 3 Reserved. Write as 0.

Prescaler. This field controls a 6-bit digital prescaler and divider. The prescaler reduces the sensitivity

of each ADC integrator as shown in the table below:

FIELD VALUE PRESCALER MODE

000 Divide by 1.

001 Divide by 2.

PRESCALER 2:0

010 Divide by 4.

PRESCALER

2:0

011 Divide by 8.

100 Divide by 16.

101 Divide by 32.

110 Divide by 64.

111 Not used.