OPT4003-Q1

The OPT4003-Q1 is a dual-channel, light-to-digital sensor (single-chip lux meter and NIR power meter) that independently measures the intensity of visible and near infrared (NIR) light. To measure accurate visible light intensity, a specially engineered filter on the device tightly matches the photopic response of the human eye and rejects the near-infrared component from common light sources. The NIR channel filter is specially engineered to provide high sensitivity to wavelengths in the near infrared region while achieving high rejection of visible wavelengths with a sharp cutoff at 800 nm. The output of the OPT4003-Q1 is semi-logarithmic with binary logarithmic full-scale light ranges along with a highly linear response within each range. The visible channel provides nine binary light ranges, providing measurement capability from 535 µlux to 143 klux and 28 bits of effective dynamic range. The NIR channel provides seven light ranges, providing measurement capability from 409 pW/cm2 to 27 mW/cm2 and 26 bits of effective dynamic range. The built-in automatic range selection logic dynamically adjusts the device gain settings based on the light level, providing the best possible resolution in all conditions without user input.

The OPT4003-Q1 is equipped with engineered optical filters on both channels, providing strong out-of-band rejection. Strong infrared rejection on the visible channel aids in maintaining high lux accuracy across all light sources, especially when the sensor is placed under dark glass for aesthetic reasons. The NIR channel robust rejection of visible wavelengths and sharp cutoff at 800 nm enables precise near-infrared measurements under mixed lighting conditions, including high levels of visible light.

The OPT4003-Q1 is designed for systems that require light level detection to enhance user experience and typically replaces low-accuracy photodiodes, photoresistors, and other ambient light sensors with underwhelming human eye matching and near-infrared rejection.

The OPT4003-Q1 can be configured to operate with light conversion times from 600 µs to 800 ms per channel in 12 steps, providing system flexibility based on application need. Conversion time includes the light integration time and analog-to-digital (ADC) conversion time. Measurement resolution is determined by a combination of light intensity and integration time, effectively providing the capability to measure down to 535 µlux of light intensity changes.

Digital operation is flexible for system integration. Measurements can be either continuous or triggered in one shot with register writes or a hardware pin. The device features a threshold detection logic, which allows the processor to sleep while the sensor waits for an appropriate wake-up event to report through the interrupt pin.

The sensor reports a digital output representing the light level over an I2C- and SMBus-compatible, two-wire serial interface. An internal first-in-first-out (FIFO) on the output registers is available to read out measurements from the sensor at a slower pace while still preserving all data captured by the device. The OPT4003-Q1 also supports I2C burst mode, thus helping the host read data from the FIFO with minimal I2C overhead.

The low power consumption and low power-supply voltage capability of the OPT4003-Q1 helps enhance the battery life of battery-powered systems.