ISL29013 View Datasheet(PDF) - Renesas Electronics
Part Name
Description
Manufacturer
ISL29013
Renesas Electronics
ISL29013 Datasheet PDF : 14 Pages
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ISL29013
Control Register 01(hex)
The Read/Write control register has three functions:
1. Interrupt flag; Bit 5. This is the status bit of the interrupt. The
bit is set to logic high when the interrupt thresholds have
been triggered, and logic low when not yet triggered.
Writing a logic low clears/resets the status bit.
BIT 5
0
1
TABLE 8. INTERRUPT FLAG
OPERATION
Interrupt is cleared or not triggered yet
Interrupt is triggered
2. Range/Gain; Bits 3 and 2. The Full Scale Range can be
adjusted by an external resistor Rext and/or it can be
adjusted via I2C using the Gain/Range function.
Gain/Range has four possible values, Range(k) where k is
1 through 4. Table 9 lists the possible values of Range(k)
and the resulting FSR for some typical value REXT
resistors.
TABLE 9. RANGE/GAIN TYPICAL FSR LUX RANGES
BITS
3:2 k RANGE(k)
0:0 1 2,000
FSR LUX
RANGE@
REXT = 100k
2,000
FSR LUX
RANGE@
REXT = 50k
4,000
FSR LUX
RANGE@
REXT = 500k
400
0:1 2 8,000
8,000
16,000
1,600
1:0 3 32,000
32,000
64,000
6,400
1:1 4 128,000
128,000
256,000
25,600
Interrupt persist; Bits 1 and 0. The interrupt pin and the
interrupt flag is triggered/set when the data sensor reading is
out of the interrupt threshold window after m consecutive
number of integration cycles. The interrupt persist bits
determine m.
TABLE 10. INTERRUPT PERSIST
BITS 1:0
NUMBER OF INTEGRATION CYCLES
0:0
1
0:1
4
1:0
8
1:1
16
Interrupt Threshold HI Register 02(hex)
This register sets the HI threshold for the interrupt pin and the
interrupt flag. By default the Interrupt threshold HI is FF(hex).
The 8-bit data written to the register represents the upper MSB
of a 16-bit value. The LSB is always 00(hex).
Interrupt Threshold LO Register 03(hex)
This register sets the LO threshold for the interrupt pin and the
interrupt flag. By default the Interrupt threshold LO is 00(hex).
The 8-bit data written to the register represents the upper MSB
of a 16-bit value. The LSB is always 00(hex).
Sensor Data Register 04(hex) and 05(hex)
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 very 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 I2C.
This value can be used to eliminate noise 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.
TABLE 11. DATA REGISTERS
ADDRESS
(hex)
CONTENTS
04
Least-significant byte of most recent sensor reading.
05
Most-significant byte of most recent sensor reading.
06
Least-significant byte of timer counter value
corresponding to most recent sensor reading.
07
Most-significant byte of timer counter value
corresponding to most recent sensor reading.
Calculating Lux
The ISL29013’s output codes, DATA, are directly proportional
to lux.
E = DATA
(EQ. 1)
The proportionality constant 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 .
= F----2-S--n--R---
(EQ. 2)
Full Scale Range (FSR), is determined by the software
programmable Range/Gain, Range(k), in the command
register and an external scaling resistor REXT which is
referenced to 100k.
FSR = Rangek -1-R--0---E0----Xk---T---
(EQ. 3)
FN6485 Rev 3.00
November 11, 2011
Page 6 of 14
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