The LX1972 is a low cost silicon light sensor with spectral response that closely emulates the human eye. The patented circuit produces a maximum spectral response of 5% nm, less than IR with a response, maximum response, above nm.
The photographic sensor is an array of PIN diodes with a linear, precise and highly repeatable current transfer function.
High-gain current mirrors on the chip multiply the photographic current of the PIN diode at a sensitivity level that can be scaled with an external resistor of standard value. The output current of this simple two-pin device can be used directly or converted to a voltage by placing it in series with a single resistor on either of its two pins.
The dynamic range is determined by the resistors (normally in the range of 10 K to 100 K) and the values of the power supply. Normally, the LX1972 only needs 1.8 V of space to operate at 1000 Lux illumination.
The internal temperature compensation allows the dark current to remain below zero over the full specification.
Temperature range (-40 to + 85 ° C), providing high precision at low light levels. The range of usable ambient light conditions is from 1 to more than 5000 Lux.
The LX1972 is optimized to control back lighting systems in low-cost consumer products such as LCD TVs, laptops and digital cameras.
- Spectral response of the nearby human eye.
- Very low IR sensitivity.
- Highly precise and repeatable output current compared to light.
- Scalable output voltage!
- Stable temperature
- High gain photographic amplifiers integrated.
- No optical filters are needed.
Specifications
Resources
Tutorial