1 Features
• High precision, high speed light-to-digital
conversion over high speed I2C interface in two
package variants
• Precision optical filtering to closely match human
eye with excellent near infrared (IR) rejection
• Semi-logarithmic output with 9 binary logarithmic
full-scale light range and highly linear response
within each range
• Built-in automatic full-scale light range selection
logic, which switches measurement range based
on input light condition with excellent gain
matching between ranges
• 28 bits of effective dynamic range from
– 312.5 μlux to 83 klux for PicoStar™ package
variant
– 437.5 μlux to 117 klux for SOT-5x3 package
variant
• 12 configurable conversion times from 600 μs to
800 ms is an excellent choice for a wide variety of
high speed and high precision applications
• External pin interrupt for hardware synchronized
trigger and interrupts (only on SOT-5X3 package
variant)
• Internal FIFO for output registers with I2C burst
readout
• Low operating current: 30 μA
with ultra-low power standby: 2 μA
• Operating temperature range: –40°C to +85°C
• Wide power-supply range: 1.6 V to 3.6 V
• 5.5 V Tolerant I/O pins
• Selectable I2C address
• Small-form factor
– PicoStar™ package: 0.84 mm x 1.05 mm x
0.226 mm
– SOT-5X3: 2.1mm x 1.9mm x 0.6mm

2 Applications
• Display backlight controls for
– Smartwatches, wearable electronics, and
health fitness bands
– Tablets and notebooks
– Multi-function printers
– Home automation interfaces
– Thermostats and home automation appliances
• Lighting control systems to detect light level (day
or night)
• Point-of-sale terminals
• Outdoor traffic and street lighting
• IP Network Cameras
• Flicker rate detection of light sources

3 Description
The OPT4001 is a light-to-digital sensor (single chip
lux meter) that measures the intensity of visible
light. The spectral response of the sensor tightly
matches the photopic response of the human eye. A
specially engineered filter on the device rejects nearinfrared
component from the common light sources to
measure accurate light intensity. Output of OPT4001
is semi-logarithmic with 9 binary logarithmic full-scale
light ranges along with highly linear response within
each range, bringing capability to measure from
312.5 μlux to 83 klux for PicoStar™ variant and
437.5 μlux to 117 klux for the SOT-5X3 variant.
This capability allows light sensor to have 28-bit
effective dynamic range. With built-in automatic fullscale
range selection, logic users do not have to
select appropriate gain settings based on light levels.