BH1721FVC-TR Rohm Semiconductor, BH1721FVC-TR Datasheet - Page 5

• Manufacturer Part Number: BH1721FVC-TR
• Description: Industrial Optical Sensors Ambient Light Sensor Digital 16bit Serial
• Manufacturer: Rohm Semiconductor
• Type: Ambient Light Sensor with Digital Outputr

Specifications of BH1721FVC-TR

• Product: Ambient Light Sensor
• Wavelength: 560nm
• Output Type: I²C™
• Package / Case: SOT-665
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

●Instruction Set Architecture
●Measurement mode explanation
© 2010 ROHM Co., Ltd. All rights reserved.
BH1721FVC
www.rohm.com
We recommend to use H-Resolution Mode.
Power Down
Power On
Continuously Auto-Resolution Mode
Continuously H-Resolution Mode
Continuously L-Resolution Mode
Change Measurement time
( High bit )
Change Masurement time
( Low bit )
※ Don't input the other opecode.
Data output at H-resolution mode after
120ms passes from measurement start.
Measurement Mode
Measurement time (integration time) of H-Resolution Mode is so long that some kind of noise (including in 50Hz / 60Hz
noise) is rejected. And H-Resolution Mode is 1 lx resolution so that it is suitable for darkness (less than 20 lx)
Auto-Resolution mode selects measurement mode automatically. It is determined after 16ms (typ.) passes from
measurement start. If BH1721FVC judges that current illuminance is more than 4000 lx, then Data is output at L-resolution
mode, else Data is output after 120ms(typ.) from measurement start at H-resolution mode. Please refer below flow chart.
H-Resolution Mode
L-Resolution Mode
Lux <= 4000
Instruction
Measurement Time.
Select mode
Typ. 120ms
Typ. 16ms
Start
010_MT[9,8,7,6,5]
011_MT[4]_XXXX
after 16ms.(typ.)
DATA output at L-resolution mode
0000_0000
0000_0001
0001_0000
0010_0000
0001_0010
0010_0010
0001_0011
0001_0110
0010_0011
0010_0110
Opecode
Lux > 4000
Measurement Range.
Auto-Resolution mode measurement
0 - 65528 lx
0 - 8191 lx
5/15
No active state.
Waiting for measurement command.
Switch measurement mode automatically by illuminance.
Start measurement at 1lx resolution.
Measurement Time is typically 120ms.
Start measurement at 8lx resolution.
Measurement Time is typically 16ms.
Change measurement time.
※ Please refer "adjust measurement result for influence of optical window."
Change measurement time.
※ Please refer "adjust measurement result for influence of optical window."
Resolution
1 lx
8 lx
Comments
Technical Note
2010.02 - Rev.A