Dec 30 2010
Maxim Integrated Products recently launched the MAX9635, a digital ambient-light sensor (ALS) with an adaptive gain block. It has been designed with the company's BiCMOS technology, and combines two photodiodes, an ADC, and requisite digital functions into a 2mm x 2mm package, saving a lot of space.
It is energy efficient, making batteries last longer. It also provides a 4,000,000 to 1range to ensure accurate lux readings in all light conditions. It is suitable for tablet and notebook PCs, smart phones, televisions, digital lighting-management systems, and light-intensity monitoring applications.
It improves display performance and is used in display and lighting applications. With ALS solutions, it helps users to adjust display brightness based on light availability. Because backlighting is quite expensive, controlling brightness can mean greater power savings.
The BiCMOS technology helps in the integration of two photodiodes with an optical filter to repel UV and infrared light, allowing the sensor to replicate the visual response of the human eye to measure light in various settings. Advanced algorithms amend spectra variations between light sources, making for an accurate lux response. Moreover, its low-light sensitivity makes it an ideal choice in applications where the IC is located behind black glass that reduces the ambient light.
It can operate from 1.8V, powered by the same supply as the I2C interface. This helps lessen power consumption and requires a single voltage rail. An address pin allows two sensors on the same I2C bus.
A built-in interrupt facility further reduces the frequency of I2C communications, initiating connection with the microcontroller only when the ambient-light is more than the programmed threshold. This mitigates the need to monitor it continuously.