The SFH 5712 from OSRAM Opto Semiconductors detects ambient brightness in the same way as the human eye, and is the only sensor on the market that offers not only standard data rates but also high speed rates of up to 3.4 MHz. Without the need for any additional control commands, an integrated circuit in the sensor automatically provides a measured value between 3 and 65,000 lx twice a second. The sensor has only four connections and takes up very little space, measuring just 2 x 2 x 0.7 mm. It can be easily controlled via its integrated I²C interface.
"The benefits of our digital ambient light sensor are obvious", said Dr. Werner Kuhlmann, Development Manager for Silicon Detectors at OSRAM Opto Semiconductors. "The sensor digitally transmits the true lux value so there is no need for complicated formulas to calculate an appropriate value from the output signal. This saves one operation in the application. It is also insensitive to mains-power related 50-60 Hz flickering that is produced for example by fluorescent lamps." With 150 µA during operation and only 1.5 µA in stand-by mode the sensor consumes very little power.
The SFH 5712 is primarily intended for mobile applications in which the brightness of the display is constantly adjusted according to available ambient light. This extends the interval between recharges and therefore improves the service life of the devices. The main beneficiaries are cell phones, PDAs, navigation devices, notebooks and laptops. Ambient light adjusted brightness also improves readability.
A good legible display on satellite navigation devices is not just highly convenient but also an important safety aspect.
OSRAM has added the first digital ambient light sensor to its product portfolio so it can now offer the right sensor for a wide range of requirements and for every area of application.
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