ams AG - global leader in the design and manufacture of high performance analog ICs (integrated circuits)

TSL2540 Ambient Light Sensor

Light-to-Digital Converter with I²C interface


The TSL2540 is a very-high sensitivity light-to-digital converter that approximates the human eye response to light intensity under varying lighting conditions and transforms this light intensity to a digital signal output capable through a 1.8V I²C interface. The ALS sensor features 2 output channels, a visible channel and an IR channel. The visible channel has a photodiode with a photopic Interferometric UV and IR blocking filter and the IR channel has a photodiode with an IR pass filter. Each channel has a dedicated integrating data converter which converts photodiode current into a 16-bit digital output. This digital output can be interfaced with a microprocessor where illuminance in lux is derived to accurately measure ambient light to control a displays baklight. 

Key Features

  • Integrated on-chip photopic filter    
  • High Sensitivity down to mLux levels
  • 0.18µm process technology with 1.8V I²C
  • 1M:1 dynamic range
  • Automatic AUTO Zero/Dark Count control

Key Benefits

  • Provides near photopic responsiveness
  • Design flexibility for dark glass & placement
  • Reduces power consumption
  • Enables dark room to sunlight operation
  • Eliminates system electrical background noise   

Product Facts

Supply Voltage [V] 1.7 - 2.0
Interface I²C - 1.8V
Programmable Gain, Integration Time, Interrupt
Maximum Lux 1,3
Temperature Range [°C] -30 to +85
Packages QFN, Pin Count 10

Additional Information

  • Home assistants
  • Smartwatch wearables
  • Display backlight control
  • Tablets
  • Smartphones
  • Display Backlight Control
  • Medical diagnostics