ALS-PDIC17-79NB-TR8_15 Datasheet, PDF (10/19 Pages) Everlight Electronics Co., Ltd – Digital Ambient Light Sensor

DATASHEET
SMD  I²C Digital Ambient Light Sensor
ALS-PDIC17-79NB/TR8
Theory of Operation
The photocurrent, generated by the built-in photodiode while being illuminated, is proportionally converted to
frequency; the digital frequency signal is then integrated by a 15-bit counter for a predetermined period of time (Tint).
This period of time is called integration time which can be adjusted by changing the nominal value of the resistor
between the RINT and GND terminals. The converted data are read out through a two-wire, I²C Interface bus. Since the
photodiode has been specially processed to suppress the spectral response in infrared region, the readout is very close
to the photopic transfer function, v(λ), which is the mathematic expression of human-eye's response to ambient light.
Address Option for I²C
The I²C address is determined before placing an order; users can assign any one of the three addresses (0x39,
0x29, 0x44) for their specific application. Without any prior request for a specific I2C address, the default address is
0x39.
Address Pin
Configuration
Floating
Tied to GND
Tied to VCC
I²C Address
0x39 (default)
0x29
0x44
Table 1 Connecting options of I²C address
ADC Register
The ADC register contains 16 bits with a 15-bit wide data from D0 to D14 and a valid bit D15. The register is
divided into two groups; D[15..8] is the most significant (MS) byte and D[7..0] is the least significant (LS) byte. See Table
2 for details.
Valid Bit
Data Bits
D15
D14 D13 ~ D8 D7~D1
D0
MSB
LSB
Most Significant (MS) byte
Least Significant (LS) byte
Table 2 ADC Register Structure
Revi1si0on _Copy:_rig3_{ht © 2010, Everlight All Rights Reserved. Release Date : 3.5.2012. Issue No: D}R_LSe_-l₀e₀a₀₀s₀e₃₄Date:2012-03-1_w6_w1_w2_.:_e0_v0_e:_r3_li3_g._h0_t.com
LifecyclePhase:
Expired Period: Forever