ISL29010IROZ-EVALZ Intersil, ISL29010IROZ-EVALZ Datasheet - Page 6

• Manufacturer Part Number: ISL29010IROZ-EVALZ
• Description: EVALUATION BOARD FOR ISL29010
• Manufacturer: Intersil

Specifications of ISL29010IROZ-EVALZ

• Sensor Type: Light, Digital Output
• Sensing Range: 128000Lux
• Interface: I²C
• Sensitivity: 540nm
• Voltage - Supply: 2.5 V ~ 3.3 V
• Embedded: No
• Utilized Ic / Part: ISL29010
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Control Register 01(hex)
The Read/Write control register has one function:
I
When the device is configured to output a signed 15-bit data,
the most significant byte is accessed at 04(hex), and the
least significant byte can be accessed at 05(hex). The
sensor data register is refreshed after every integration
cycle.
Timer Data Register 06(hex) and 07(hex)
Note that the timer counter value is only available when
using the External Timing Mode. The 06(hex) and 07(hex)
are the LSB and MSB, respectively, of a 16-bit timer counter
value corresponding to the most recent sensor reading.
Each clock cycle increments the counter. At the end of each
integration period, the value of this counter is made available
over the I
introduced by slight timing errors caused by imprecise
external timing. Microcontrollers, for example, often cannot
provide high-accuracy command-to-command timing, and
the timer counter value can be used to eliminate the
resulting noise.
Calculating Lux
The ISL29010’s output codes, DATA, are directly
proportional to lux.
E
BITS
2
1. Range/Gain; Bits 3 and 2. The Full Scale Range can be
3:2
0:0
0:1
1:0
1:1
ADDRESS
Sensor Data Register 04(hex) and 05(hex)
=
adjusted by an external resistor R
adjusted via I
Gain/Range has four possible values, Range(k) where k
is 1 through 4. Table 8 lists the possible values of
Range(k) and the resulting FSR for some typical value
R
(hex)
α
TABLE 8. RANGE/GAIN TYPICAL FSR LUX RANGES
04
05
06
07
EXT
×
1
2
3
4
k RANGE(k)
DATA
2
resistors.
C. This value can be used to eliminate noise
128,000
32,000
2,000
8,000
Least-significant byte of most recent sensor reading.
Most-significant byte of most recent sensor reading.
Least-significant byte of timer counter value
corresponding to most recent sensor reading.
Most-significant byte of timer counter value
corresponding to most recent sensor reading.
TABLE 9. DATA REGISTERS
2
C using the Gain/Range function.
R
RANGE@
EXT
FSR LUX
128,000
32,000
2,000
8,000
= 100k
6
CONTENTS
R
RANGE@
FSR LUX
EXT
256,000
EXT
16,000
64,000
4,000
= 50k
and/or it can be
R
RANGE@
EXT
FSR LUX
25,600
1,600
6,400
400
(EQ. 1)
= 500k
ISL29010
The proportionality constant α is determined by the Full
Scale Range (FSR), and the n-bit ADC, which is user
defined in the command register. The proportionality
constant can also be viewed as the resolution; the smallest
lux measurement the device can measure is α in Equation 2.
α
Full-Scale Range (FSR) is determined by the software
programmable Range/Gain, Range(k), in the command
register and an external scaling resistor R
referenced to 100kΩ.
FSR
The transfer function effectively for each timing mode
becomes:
INTERNAL TIMING MODE
EXTERNAL TIMING MODE
Gain/Range, Range(k)
The Gain/Range can be programmed in the control register
to give Range(k) determining the FSR. Note that Range(k) is
not the FSR (see Equation 3). Range(k) provides four
constants depending on programmed k that will be scaled by
R
adjusts the FSR. This function is especially useful when light
conditions are varying drastically while maintaining excellent
resolution.
E
E
EXT
=
n = 3, 7, 11, or 15. This is the number of clock cycles
programmed in the command register.
Range(k) is the user defined range in the Gain/Range bit
in the command register.
R
pin.
DATA is the output sensor reading in number of counts
available at the data register.
2
Internal Timing Mode. For the External Timing Mode, the
maximum number of counts is stored in the data register
named COUNTER.
COUNTER is the number of increments accrued between
integration time for External Timing Mode.
=
=
n
EXT
FSR
------------
Range k ( )
----------------------------------------------------
Range k ( )
----------------------------------------------------
=
represents the maximum number of counts possible in
2
(see Table 8). Unlike R
n
Range k ( )
COUNTER
is an external scaling resistor hardwired to the R
2
n
×
×
100kΩ
----------------- -
100kΩ
----------------- -
R
R
×
EXT
EXT
100kΩ
----------------- -
R
EXT
×
×
DATA
DATA
EXT
, Range(k) dynamically
EXT
, which is
February 13, 2008
FN6414.0
(EQ. 5)
(EQ. 4)
(EQ. 2)
(EQ. 3)
EXT