TSL1402R
256 ?1 LINEAR SENSOR ARRAY WITH HOLD
TAOS041G NOVEMBER 2011
3
The LUMENOLOGY r Company
r
r
Copyright E 2011, TAOS Inc.
www.taosinc.com
AO is an op amp-type output that does not require an external pull-down resistor. This design allows a rail-to-rail
output voltage swing. With V
DD
= 5 V, the output is nominally 0 V for no light input, 2 V for normal white level, and 4.8 V
for saturation light level. When the device is not in the output phase, AO is in a high-impedance state.
The voltage developed at analog output (AO) is given by:
V
out
= V
drk
+ (R
e
) (E
e
)(t
int
)
where:
V
out
is the analog output voltage for white condition
V
drk
is the analog output voltage for dark condition
R
e
is the device responsivity for a given wavelength of light given in V/(糐/cm
2
)
E
e
is the incident irradiance in 糤/cm
2
t
int
is integration time in seconds
The TSL1402R can be connected in the serial mode, where it takes 256 clocks to read out all pixels, or in the
parallel mode where it takes 128 clocks to read out all pixels (see APPLICATION INFORMATION and FIgures
9 and 10).
A 0.1 糉 bypass capacitor should be connected between V
DD
and ground as close as possible to the device.