tcs3771 ETC-unknow, tcs3771 Datasheet - Page 12

• Manufacturer Part Number: tcs3771
• Description: Color Light-to-digital Converter With Proximity Sensing
• Manufacturer: ETC-unknow

TCS3771
COLOR LIGHT-TO-DIGITAL CONVERTER
with PROXIMITY SENSING
TAOS110A − MARCH 2011
12
Copyright E 2011, TAOS Inc.
The proximity integration time (PTIME) is the period of time that the internal ADC converts the analog signal
to a digital count. It is recommend that this be set to a minimum of PTIME = 0xFF or 2.4 ms.
The combination of LED power and number of pulses can be used to control the distance at which the sensor
can detect proximity. Figure 12 shows an example of the distances covered with settings such that each curve
covers 2
×
1000
800
600
400
200
the distance. Counts up to 64 pulses provide a 16
0
1
y
2
y
4
y
8
y
Figure 11. Proximity IR LED Waveform
100 mA,
4 Pulses
25 mA,
1 Pulse
Background
100 mA,
1 Pulse
LED On
r
Add IR +
100 mA,
16 Pulses
PROXIMITY ADC COUNT
RELATIVE DISTANCE
www.taosinc.com
Relative Distance
14 ms
16
Figure 12
y
Subtract
Background
LED Off
vs.
100 mA,
64 Pulses
IR LED Pulses
×
range.
r
The LUMENOLOGY r Company