TSL27711FN TAOS, TSL27711FN Datasheet - Page 9

• Manufacturer Part Number: TSL27711FN
• Description: Light to Digital Converters Light to Digital w/Proximity
• Manufacturer: TAOS

Specifications of TSL27711FN

• Data Bus Width: 16 bit
• Peak Wavelength: 640 nm, 850 nm
• Maximum Operating Frequency: 795 KHz
• Operating Supply Voltage: 2.4 V to 3.6 V
• Operating Current: 175 uA
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: - 30 C
• Interface Type: I2C
• Maximum Fall Time: 300 ns
• Maximum Rise Time: 300 ns
• Mounting Style: SMD/SMT
• Resolution: 16 bit
• Package / Case: DFN-6
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ALS Operation
The LUMENOLOGY r Company
The ALS engine contains ALS gain control (AGAIN) and two integrating analog-to-digital converters (ADC) for
the clear and IR photodiodes (Figure 7). The ALS integration time (ATIME) impacts both the resolution and the
sensitivity of the ALS reading. Integration of both channels occurs simultaneously and upon completion of the
conversion cycle, the results are transferred to the clear and IR data registers (CDATAx and IR DATAx). This
data is also referred to as channel count. The transfers are double-buffered to ensure that invalid data is not
read during the transfer. After the transfer, the device automatically moves to the next state in accordance with
the configured state machine.
The ALS gain can be set to amplify the clear channel and IR channel by 1, 8, 16, or 120
CONTROL (r0x0F, b1:0) are used to set the gain.
Integration time can be set from 2.7ms to 700ms. The registers for programming the integration and wait times
are a 2’s compliment values. The actual time can be calculated as follows:
Inversely, the time can be calculated from the register value as follows:
For example, if a 100-ms integration time is needed, the device needs to be programmed to:
Conversely, the programmed value of 0xC0 would correspond to:
ATIME = 256 − Integration Time / 2.72 ms
Integration Time = 2.72 ms
256 − (100 / 2.72) = 256 − 37 = 219 = 0xDB
(256 − 0xC0)
Clear
IR
2.72 ms to 700 ms
AGAIN(r 0x0F, b1:0)
1y, 8y, 16y, 120y Gain
×
r
Clear
ALS
ADC
ALS Control
IR
2.72 = 64
Figure 7. ALS Operation
ATIME(r 1)
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Clear
Data
Data
IR
×
×
2.72 = 172 ms.
(256 − ATIME)
IRDATAH(r 0x17), IRDATAL(r 0x16)
CDATAH(r 0x15), CDATAL(r 0x14)
LIGHT-TO-DIGITAL CONVERTER
r
with PROXIMITY SENSING
TAOS100A − FEBRUARY 2010
Copyright E 2010, TAOS Inc.
×
. The register bits
TSL2771
9