ISL76671 Datasheet, PDF (7/9 Pages) Intersil Corporation – Low Power, <100 Lux Optimized, Analog Output Ambient Light Sensor

ISL76671
Application Information
Light-to-Voltage Conversion
The ISL76671 has responsiveness that is a square-root function
of the light intensity intercepted by the photodiode in lux.
Because the photodiode has a responsivity that resembles the
human eye, conversion rate is independent of the light source
(fluorescent light, incandescent light or direct sunlight).
V_OUT
=
-----¹---⁸----^μ----^A------
100 l u x
E × R_EXT
(EQ. 1)
In Equation 1, V_OUT is the output voltage, E is the light intensity
and R_EXT is the value of the external resistor. The R_EXT is used to
set the light-to-voltage scaling constant. The compliance of the
ISL76671's output circuit may result in premature saturation
when an excessively large R_EXT is used. A R_EXT value of 100kΩ is
recommended for automotive applications. The output
compliance voltage is 700mV below the supply voltage as listed
in V_O-MAX of the “Electrical Specifications” table on page 3.
Optical Sensor Location Outline
The green area in Figure 20 shows the optical sensor location
outline of ISL76671. Along the pinout direction, the center line
(CL) of the sensor coincides with that of the packaging. The
sensor width in this direction is 0.39mm. Perpendicular to the
pinout direction, the CL of the sensor has an 0.19mm offset from
the CL of packaging away from pin 1. The sensor width in this
direction is 0.46mm.
2.10mm
2.00mm
0.19mm
0.39mm
FIGURE 20. 6 LD ODFN SENSOR LOCATION OUTLINE
0.46mm
7
FN7716.1
December 12, 2011