EVALUATION KIT AVAILABLE
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
General Description
Features
The MAX44005 integrates 7 sensors in one product: red,
green, blue (RGB) sensors; an ambient light (clear) sensor; a temperature sensor; an ambient infrared sensor,
and an infrared proximity sensor with an I2C interface.
This highly integrated optical sensor includes a temperature sensor to improve reliability and performance.
S Optical Sensor Fusion for True Color Sensing
7 Parallel ADCs
R, G, B, IR, ALS, Proximity Sensing
Temperature Sensing
The IC computes all the light information with parallel
data converters to make simultaneous light measurement
in a very short time. The chip consumes only 15FA in
RGBC + IR mode and operates at 1.8V supply voltage.
S Optimized for System Power Efficiency
10µA in Ambient Mode
15µA in RGBC + IR Mode
0.01µA in Shutdown Mode
The IC’s RGB sensing capability improves the performance of end products by providing robust and precise
information for ambient color sensing and color temperature measurement.
S Integrated 1-Pulse IR LED Driver for Proximity
Sensing
Improved Sensitivity and Power Saving
Sunlight Rejection
The integrated proximity sensor uses a single-pulse LED
scheme to achieve very low power consumption. This
method also improves sunlight rejection and 50Hz/60Hz
noise to deliver reliable proximity measurements. With this
technology, the IC is a perfect solution for touch-screen
portable devices and presence detection applications.
S Digital Functionalities
Programmable Channel Gains
Adjustable Interrupt Thresholds
S Superior Sensitivity
0.001 Lux
S High-Level Integration
7 Sensors in a 2mm x 2mm x 0.6mm Package
Functional Diagram
The on-chip ambient sensor has the ability to make wide
dynamic range 0.002~8388.61FW/cm2 measurements.
The IC’s digital computation power provides programmability and flexibility for end-product design. A programmable interrupt pin minimizes the need to poll the
device for data, freeing up microcontroller resources,
and reducing system software overhead, and ultimately,
power consumption. All these features are included in a
tiny, 2mm x 2mm x 0.6mm optical package.
VCC
VLED
MAX44005
RED
GREEN
BLUE
Applications
CLEAR
Smartphones
Presence Detection
Tablet PCs
Industrial Sensors
TVs/Displays
Color Correction
AMB
PGA
14-BIT
ADC
AMB
PGA
14-BIT
ADC
AMB
PGA
14-BIT
ADC
AMB
PGA
14-BIT
ADC
AMB
PGA
14-BIT
ADC
IRLED
SDA
SCLK
I2C
COMP
IR
Ordering Information appears at end of data sheet.
INT
14-BIT
ADC
TEMP
Digital Light
Management
µC
AMB
PGA
14-BIT
ADC
AMBIENT
CANCELLATION
AMB
PGA
DRV
GND
GND
For related parts and recommended products to use with this part, refer to: www.maximintegrated.com/MAX44005.related
For pricing, delivery, and ordering information, please contact Maxim Direct at
1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.
19-6292; Rev 1; 10/12
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
ABSOLUTE MAXIMUM RATINGS
Continuous Input Current into Any Terminal.................... ±20mA
Output Short-Circuit Current Duration........................Continuous
Operating Temperature Range........................... -40NC to +85NC
Soldering Temperature (reflow).......................................+260NC
VCC to GND...........................................................-0.3V to +2.2V
DRV, INT, SCL, SDA to GND...................................-0.3V to +6V
Continuous Power Dissipation
(derate 11.9mW/NC above +70NC)...............................953mW
PACKAGE THERMAL CHARACTERISTICS (Note 1)
OTDFN
Junction-to-Ambient Thermal Resistance (BJA)........83.9NC/W
Junction-to-Case Thermal Resistance (BJC)................37NC/W
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VCC = 1.8V, TA = +25NC, TMIN–TMAX are from -40NC to +85NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
COLOR SENSOR CHARACTERISTICS
Maximum Sensitivity (Note 3)
Maximum Sense Capability
Clear = 538nm
0.002
Red = 630nm
0.002
Green = 538nm
0.002
Blue = 470nm
0.004
Infrared = 850nm
0.002
Clear = 538nm
8388
Red = 630nm
8388
Green = 538nm
8388
Blue = 470nm
Infrared = 850nm
Total Error
TE
Gain Matching
Power-Up Time
Power = 10FW/cm2
Red = 630nm,
Green = 538nm,
Blue = 470nm,
Clear = 538nm,
IR = 850nm
TA = +25NC
Red to green to blue, TA = +25NC
FW/cm2
16,777
8388
2
15
0.5
10
10
tON
Dark Level Counts
6.25ms conversion time, 0 lux, TA = +25NC
ADC Conversion Time
14-bit resolution (Note 4)
Maxim Integrated
FW/cm2
%
ms
2
400
%
Counts
ms
2
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
ELECTRICAL CHARACTERISTICS (continued)
(VCC = 1.8V, TA = +25NC, TMIN–TMAX are from -40NC to +85NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
ADC Conversion Time
CONDITIONS
MIN
TYP
14-bit resolution, TA = +25NC
100
12-bit resolution
25
10-bit resolution
6.25
8-bit resolution
1.5625
MAX
UNITS
ms
TA = +25NC
1
10
TA = -40NC to +85NC
2
15
Infrared Receiver Sensitivity
850nm IR LED
2
FW/cm2
Maximum Infrared Receiver
850nm IR LED
16,777
FW/cm2
ADC Conversion Accuracy
%
INFRARED PROXIMITY RECEIVER
ADC Conversion Time
10-bit resolution
6.25
8-bit resolution
1.5625
Sunlight Rejection
ms
100,000
lux
10
mA
INFRARED LED TRANSMITTER
Minimum IR LED Drive Current
IDRV
Maximum IR LED Drive Current
IDRV
Drive Current Accuracy
110
mA
IOUT = 110mA, VDRV = 1.5V
15
IOUT = 50mA, VDRV = 1.5V
15
IOUT = 10mA, VDRV = 1.5V
%
15
IOUT = 110mA, D IOUT = 2%
0.5
3.6
V
Main Voltage of DRV Pin
IOUT = 100mA, D IOUT = 5%
0.3
3.6
V
Burst-On/Burst-Off Ratio
AMBTIM[2:0] = 100,
PRXTIM = 0,
MODE[2:0] = 011
0.03
TA = +25NC~+55NC
±1
±3
TA = +0NC~+70NC
±2
±5
Main Voltage of DRV Pin
%
TEMPERATURE SENSOR
Accuracy (Note 5)
Resolution
0.25
NC
NC/LSB
POWER SUPPLY
Power-Supply Voltage
VCC
Quiescent Current
ICC
Software Shutdown Current
Maxim Integrated
ISHDN
Guaranteed by total error
1.7
2
Clear mode
10
18
RGBC + IR mode
15
30
LED on
420
550
TA = +25NC
1
V
FA
FA
3
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
ELECTRICAL CHARACTERISTICS (continued)
(VCC = 1.8V, TA = +25NC, TMIN–TMAX are from -40NC to +85NC, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.4
V
DIGITAL CHARACTERISTICS (SDA, INT)
Output Low Voltage
VOL
ISINK = 6mA
I2C Input Voltage High
VIH
SDA, SCL
I2C Input Voltage Low
VIL
SDA, SCL
Input Hysteresis
1.4
VHYS
Input Capacitance
CIN
Input Leakage Current
IIN
V
0.4
V
200
mV
10
pF
VIN = 0V, TA = +25NC
0.1
VIN = 5.5V, TA = +25NC
0.1
FA
I2C TIMING CHARACTERISTICS (Note 5)
Serial-Clock Frequency
fSCL
Bus Free Time Between STOP
and START
tBUF
1.3
Fs
Hold Time (REPEATED) START
Condition
tHD,STA
0.6
Fs
Low Period of the SCL Clock
tLOW
1.3
Fs
High Period of the SCL Clock
tHIGH
0.6
Fs
Setup Time for a REPEATED
START
tSU.STA
0.6
Fs
Setup Time for STOP Condition
tSU,STO
0.6
Fs
Data Hold Time
tHD,DAT
Data Setup Time
tSU,DAT
Bus Capacitance
CB
SDA and SCL Receiving Rise
Time
tR
SDA and SCL Receiving Fall
Time
SDA Transmitting Fall Time
Pulse Width of Suppressed Spike
Note 2:
Note 3:
Note 4:
Note 5:
0
0
400
0.9
100
kHz
Fs
ns
400
pF
20 +
0.1CB
300
ns
tF
20 +
0.1CB
300
ns
tf
20 +
0.1CB
250
ns
tSP
0
50
ns
100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by bench or ATE characterization.
In AMBTIM[2:0] mode (100ms integration time).
At 14-bit resolution mode. Sensitivity is 4x higher with 400ms integration time than 100ms integration time.
Design guidance only, not production tested.
Maxim Integrated
4
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Typical Operating Characteristics
(VCC = 1.8V, TA = +25NC, TMIN–TMAX are from -40NC to +85NC, unless otherwise noted.)
100
80
60
40
2k
20
0
0
RADIATION PATTERN
RESPONSE OF CLEAR AND IR CHANNELS
WITH INCANDESCENT LIGHT
-90 -70 -50 -30 -10 10
30
50
400k
300k
0
90
225k
TEST CONDITIONS:
WHEN THE COUNT READINGS IN ONE PGA
SETTING ARE SATURATED,
CHANGE PGA SETTING
TO THE LOWER SENSITIVITY
PGA GAIN SETTING.
E.G., PGA [1:0] =
00 PGA [1:0] = 01
CENTERTRIMMED UNIT
CLEAR CHANNEL
200k
175k
150k
125k
100k
75k
50k
CLEAR CHANNEL
IR CHANNEL
0
200
400
600
10 20 30 40 50 60 70 80 90 100
RESPONSE OF CLEAR AND IR CHANNELS
WITH FLUORESCENT LIGHT
READINGS (COUNTS)
500k
0
70
800
IR CHANNEL
25k
0
1000
0
200
400
600
800
ANGLE OF INCIDENCE IN DEGREE
ILLUMINANCE (LUX)
ILLUMINANCE (LUX)
SUPPLY CURRENT vs. TEMPERATURE
LINEARITY RESPONSE vs. RGB LED
CLEAR CHANNEL RESPONSE
TO WHITE LED
200k
COUNTS
15
10
CLEAR
5
CLEAR + IR
CLEAR + RGB + IR
0
-40
-20
0
20
40
60
TEMPERATURE (°C)
Maxim Integrated
80
100
CLEAR CHANNEL RESPONSE vs. GREEN LED
GREEN CHANNEL RESPONSE vs. GREEN LED
RED CHANNEL RESPONSE vs. RED LED
TEST CONDITIONS:
WHEN THE COUNT READINGS IN ONE PGA
SETTING ARE SATURATED,
CHANGE PGA SETTING
TO THE LOWER SENSITIVITY
PGA GAIN SETTING.
E.G., PGA [1:0] =
00 PGA [1:0] = 01
150k
100k
100k
10k
COUNTS READINGS
TEST CONDTIONS:
AMBTIM[2:0] = 000,
ALL PGA SETTING = 0
1k
100
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
10
50k
BLUE CHANNEL RESPONSE vs. BLUE LED
0
0
100
200
300
POWER DENSITY (µW/cm2)
400
1000
MAX44005 toc09
250k
MAX44005 toc07
25
SUPPLY CURRENT (µA)
600k
100k
PARALLEL TO DIP PINS DIRECTION
PERPENDICULAR TO DIP PINS DIRECTION
96
0
200k
20
20
TEST CONDITIONS:
WHEN THE COUNT READINGS IN ONE PGA
SETTING ARE SATURATED,
CHANGE PGA SETTING
TO THE LOWER SENSITIVITY
PGA GAIN SETTING.
E.G., PGA [1:0] =
00 PGA [1:0] = 01
CENTER-TRIMMED UNIT
700k
READINGS (COUNTS)
40
128
SENSING DISTANCE (mm)
800k
MAX44006/08 toc03
NORMALIZED COUNTS (%)
CLEAR CHANNEL
AMBPGA [1:0]= 00
AMBTIM [2:0] =000
60
400
900 1000
WAVELENGTH (nm)
80
160
32
FLUORESCENT
500 600 700 800
WAVELENGTH (nm)
100
192
64
300
250 350 450 550 650 750 850 950 1050
0
SUNLIGHT
MAX44005 toc03
120
TEST CONDITIONS:
PRXTIM = 1, PRXPGA = 0
850nm IR LED, ILED = 100mA
18% KODAK GRAY CARD
224
MAX44005 toc06
4k
INCANDESCENT
PROXIMITY COUNTS
6k
MAX44005 toc02
140
256
MAX44005 toc05
8k
160
MAX44005 toc08
COUNTS
10k
CLEAR
RED
GREEN
BLUE
IR
NORMALIZED RESPONSE
12k
AMBPGA[1:0] = 00
AMBTIM[2:0] = 000
COMPENSATION
DISABLED
POWER DENSITY
15.83µW/cm2
MAX44005 toc01
14k
PROXIMITY ADC COUNTS
vs. SENSING DISTANCE
SPECTRUM OF LIGHT SOURCES
FOR MEASUREMENT
COUNTS vs. WAVELENGTH
TEST CONDITION: AMBTIM [2:0] = 000
1
1
10
100
1k
10k
POWER DENSITY (µW/cm2)
5
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Typical Operating Characteristics (continued)
(VCC = 1.8V, TA = +25NC, TMIN–TMAX are from -40NC to +85NC, unless otherwise noted.)
20
15
10
0
1
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80
10
100
1k
10k
2
0
0.1
0
100k
0.2
250
MAX44005 toc13
80
60
50mA IDRV SETTING
40
20
0
0.6
0.8
150
0.4
ITOTAL
100
50
10mA IDRV SETTING
0.4
ITOTAL = ICC + IIR_LED
CLEAR + RGB + IR + PROX MODE,
100ms INTEGRATION TIME
200
TOTAL CURRENT (uA)
110mA IDRV SETTING
100
0.3
VINT (V)
TOTAL CURRENT CONSUMPTION
vs. IR LED CURRENT LEVEL
120
IDRV (mA)
6
4
IR LED CURRENT vs. OUTPUT DRIVE
VOLTAGE, IDRV vs. VDRV
0.2
8
REFERENCE METER READING (LUX)
TEMPERATURE (°C)
0
10
MAX44005 toc14
X : TEMPERATURE
Y: TEMPERATURE SENSOR READINGS
12
TEST CONDITIONS:
CLEAE + RGB + IR MODE
LIGHT SOURCE: SUNLIGHT
VCC = 1.8V
5
TEST CONDITIONS:
PROX/AMBINT INTERRUPT
CONDITION, VINT LOW
14
SINK CURRENT (mA)
25
MAX44005 toc12
16
MAX44005 toc11
Y = 0.0001x2 + 0.9709x + 1.7085
SUPPLY CURRNET (µA)
80
70
60
50
40
30
20
10
0
-10
-20
-30
-40
SINK CURRENT vs. VINT LOW
SUPPLY CURRENT vs. LUX
30
MAX44005 toc10
TEMPERATURE SENSOR READINGS (°C)
TEMPERATURE SENSOR READINGS
vs. TEMPERATURE
ICC
0
1.0
0
VDRV (V)
20
40
60
80
100
120
IR LED LEVEL (mA)
SUPPLY CURRENT
vs. TIME (ZOOM IN)
SUPPLY CURRENT
vs. TIME (ZOOM OUT)
MAX44005 toc15
MAX44005 toc16
RGBC + IR + PROX MODE
ILED = 110mA
100ms INTEGRATION TIME
IDRV
100mA/div
0A
0A
ICC
200µA/div
RGBC + IR + PROX MODE
ILED = 110mA
100ms INTEGRATION TIME
200µs/div
Maxim Integrated
0A
IDRV
100mA/div
0A
ICC
200µA/div
40ms/div
6
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Typical Operating Characteristics (continued)
(VCC = 1.8V, TA = +25NC, TMIN–TMAX are from -40NC to +85NC, unless otherwise noted.)
CLEAR CHANNEL LINEARITY RESPONSE
12k
10k
8k
6k
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
4k
2k
MAX44005 toc18
14k
16k
14k
COUNTS READINGS
16k
COUNTS READINGS
RED CHANNEL LINEARITY RESPONSE
18k
MAX44005 toc17
18k
12k
10k
8k
6k
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
4k
2k
0
0
0
50 100 150 200 250 300 350 400 450
0
POWER DENSITY (µW/cm2)
POWER DENSITY (µW/cm2)
GREEN CHANNEL LINEARITY RESPONSE
COUNTS READINGS
12k
10k
8k
6k
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
4k
2k
0
16k
14k
12k
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
10k
8k
6k
4k
2k
0
0
50 100 150 200 250 300 350 400 450
POWER DENSITY (µW/cm2)
Maxim Integrated
MAX44005 toc20
LIGHT SOURCE:
530nm GREEN LED
14k
COUNTS READINGS
16k
BLUE CHANNEL LINEARITY RESPONSE
18k
MAX44005 toc19
18k
50 100 150 200 250 300 350 400 450
0
50 100 150 200 250 300 350 400 450
POWER DENSITY (µW/cm2)
7
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Pin Configuration
TOP VIEW
SDA
SCL
INT
6
5
4
MAX44005
1
2
3
VCC
GND
DRV
Pin Description
PIN
NAME
FUNCTION
1
VCC
Power Supply
2
GND
Ground
3
DRV
IR LED Current Driver
4
Interrupt
5
INT
SCL
6
SDA
I2C Data
I2C Clock
Detailed Description
The MAX44005 combines a wide-dynamic range color
sensor capable of measuring red, green, and blue (RGB)
and infrared content of ambient light with an integrated
TEMP sensor, infrared proximity (PROX) sensor and
transmitter. The IC also has a digital I2C interface and
advanced interrupt pin functionality, making it very easy
with which to interface. The die is placed inside an optically transparent (UTDFN-Opto) package.
A photodiode array inside the IC converts the light to a
current which is then processed by low-power circuitry
into a digital bit stream. The data is then stored in an
output register that can be read by an I2C master.
The IC contains five types of photodiodes sensitive to red,
green, blue, clear, and infrared content of ambient light.
Maxim Integrated
The infrared photodiodes can be configured as either DC
ambient infrared sensor or AC proximity sensor.
In the AMB mode, photodiode signals can be directly
read by a sigma-delta ADC. The user can choose
whether to read just the CLEAR channel, or CLEAR + IR
channel or CLEAR + RGB + IR channels. Due to parallel conversion by on-chip ADCs, there is no additional
delay in making ambient light information, however, there
is a supply current change depending on whether only
1 channel is active (10FA) to whether all channels are
active (15FA).
In the proximity detect mode, the infrared proximity
photodiodes are connected to sigma-delta ADC after a
sophisticated DC ambient IR rejection front-end circuit.
This allows the proximity sensor to operate even in bright
sunlight.
Key features of the IC include high-level integration, lowpower design, small packaging, single-pulse proximity
receive operation, and interrupt pin operation.
The IC operates from a VCC of 1.7V to 2V and consumes
just 10FA current in AMB mode and 15FA in RGBC +
IR mode. The on-chip IR proximity detector DC ambient rejection circuitry is synchronized with pulsing of an
integrated IR LED transmitter to improve noise immunity
from external IR sources. This scheme also reduces IR
LED power consumption compared to alternate methods
and eliminates red-glow problems with the use of 850nm
IR LEDs. An on-chip programmable interrupt function
eliminates the need to continually poll the device for data,
resulting in a significant power saving.
Ambient Light Sensing
Ambient light sensors are designed to detect brightness in
the same way as human eyes do. To achieve this, the light
sensor needs to have a spectral sensitivity that is identical
to the photopic curve of the human eye (Figure 1).
The IC’s color sensors are designed to accurately derive
the color chromaticity and intensity of ambient light.
With parallel ADC conversion circuits, conversion data
from multiple channels can be read at the same time.
An interrupt signal can also be dynamically configured
with higher and lower thresholds and a persist timer. The
interrupt is latched until the master reads the Interrupt
Status register. This allows the master to stay in powerefficient sleep mode until a change in lighting condition
alerts it.
8
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Variation between light sources can extend beyond the
visible spectral range (e.g., fluorescent, incandescent,
and sunlight) have substantially different IR radiation
content. The IC incorporates on-chip measurement of
RGBC and IR of compensation of ambient light, allowing
accurate lux detection in a variety of lighting conditions,
as well as identification of type of light source.
On-chip user-programmable Clear, RGB, Infrared
Channel Gain registers allow the light sensor response
to also be tailored for specific applications such as when
the light sensor is placed under a colored or black glass.
Proximity Light Sensing
The proximity sensor uses an external, infrared LED
source to emit controlled amounts of radiation. When an
external object reflects back some of this infrared radiation back to the IC, it is detected by the integrated sensor photodiode. The strength of reflected light is used to
determine the object’s proximity to the sensor.
It is important to take account for the fact that different
objects at the same distance from the sensor can reflect
different amounts of infrared radiation depending on their
texture and color.
The IC includes on-chip ambient cancellation circuitry
in the receive path of the infrared proximity sensor. This
14k
12k
COUNTS
10k
scheme allows the part to operate in the presence of
large amounts of DC-ambient IR radiation (e.g., sunlight).
In addition, the use of a single-pulse technique in pulsing the external infrared LED makes the chip immune to
fixed-frequency external infrared radiation such as from
remote controls, electronic ballasts, etc., and enables
reliable proximity sensor operation.
LED Driver
The IC features a LED driver that delivers a pulsed current at the output. The pulse amplitude is programmable
through the I2C interface in steps of 10mA and from 0mA
to 110mA. A low-voltage compliance of the DRV pin
allows IR LEDs to be powered from lower voltage rails,
possibly even from a 3.6V rail. High current drive accuracy improves performance by eliminating part-to-part
variation. Since the duty ratio of the external IR LED is as
low as 0.01%, a 100mA pulse translates to only 10FA of
additional current.
Temperature Sensor
The IC also integrates a temperature sensor that can be
used for ambient temperature measurement and compensation. A nonlinear response is designed to replicate
the effect of temperature on the photodiodes used on
the chip.
AMBPGA[1:0] = 00
AMBTIM[2:0] = 000
COMPENSATION DISABLED
POWER DENSITY 15.83µW/cm2
CLEAR
RED
GREEN
BLUE
IR
8k
6k
4k
2k
0
250
350
450
550
650
750
850
950
1050
WAVELENGTH (nm)
Figure 1. Wavelength vs. Counts
Maxim Integrated
9
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Register Description
POWERREGISTER
B7
B6
B5
B4
B3
B2
B1
B0
REGISTER
ON
ADDRESS
RESET
R/W
STATE
STATUS
Interrupt Status
RESET
SHDN
PWRON
PRXINTS AMBINTS
0x00
0X04
R/W
CONFIGURATION
Main Configuration
Ambient Configuration
Proximity Configuration
MODE[2:0]
TRIM
COMPEN
TEMPEN
AMBSEL[1:0]
AMBTIM[2:0]
DRV[3:0]
PRXINTE AMBINTE
0x01
0x00
R/W
AMBPGA[1:0]
0x02
0x20
R/W
0x03
0x02
R/W
PRXTIM
PRXPGA
AMBIENT + PROXIMITY READING
Ambient CLEAR High Byte
Ambient CLEAR Low Byte
Ambient RED High Byte
Ambient RED Low Byte
Ambient GREEN High Byte
Ambient GREEN Low Byte
Ambient BLUE High Byte
Ambient BLUE Low Byte
AMB_CLEAR[13:8]
AMB_CLEAR[7:0]
AMB_RED[13:8]
AMB_RED[7:0]
AMB_GREEN[13:8]
AMB_GREEN[7:0]
AMB_BLUE[13:8]
AMB_BLUE[7:0]
Ambient INFRARED High Byte
Ambient INFRARED Low Byte
Ambient IR COMP High Byte
Ambient IR COMP Low Byte
AMB_IR[13:8]
AMB_IR[7:0]
AMB_IRCOMP[13:8]
AMB_IRCOMP[7:0]
PROXIMITY IR High Byte
PROXIMITY IR Low Byte
PROX[9:8]
PROX[7:0]
0x04
0x00
R
0x05
0x00
R
0x06
0x00
R
0x07
0x00
R
0x08
0x00
R
0x09
0x00
R
0x0A
0x00
R
0x0B
0x00
R
0x0C
0x00
R
0x0D
0x00
R
0x0E
0x00
R
0x0F
0x00
R
0x10
0x00
R
0x11
0x00
R
0x12
0x00
R
0x13
0x00
R
TEMPERATURE SENSOR
TEMP High Byte
TEMP Low Byte
TEMP[13:8]
TEMP[7:0]
INTERRUPT THRESHOLDS
AMB Upper Threshold—High Byte
AMB Upper Threshold—Low Byte
AMB Lower Threshold—High Byte
AMB Lower Threshold—Low Byte
Threshold Persist Timer
UPTHR[13:8]
UPTHR[7:0]
LOTHR[13:8]
LOTHR[7:0]
PRXPST[1:0]
PROX Upper Threshold—High Byte
PROX Upper Threshold—Low Byte
PRXUPTHR[9:8]
PRXUPTHR[7:0]
PROX Lower Threshold—High
PRXLOTHR[9:8]
Byte
PROX Lower Threshold—Low Byte
AMBPST[1:0]
PRXLOTHR[7:0]
0x14
0x00
R/W
0x15
0x00
R/W
0x16
0x00
R/W
0x17
0x00
R/W
0x18
0x00
R/W
0x19
0xFF
R/W
0x1A
0xFF
R/W
0x1B
0x00
R/W
0x1C
0x00
R/W
AMBIENT ADC GAINS
Digital Gain Trim of Clear Channel
TRIM_GAIN_CLEAR[6:0]
0x1D
0xXX
R/W
Digital Gain Trim of Red Channel
TRIM_GAIN_RED[6:0]
0x1E
0xXX
R/W
Digital Gain Trim of Green Channel
TRIM_GAIN_GREEN[6:0]
0x1F
0xXX
R/W
Digital Gain Trim of Blue Channel
TRIM_GAIN_BLUE[6:0]
0x20
0xXX
R/W
TRIM_GAIN_IR[6:0]
0x21
0xXX
R/W
Digital Gain Trim of Infrared
Channel
Maxim Integrated
10
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
The individual register bits are explained below.
Interrupt Status (0x00)
REGISTER
BIT7
BIT6
Interrupt Status
BIT5
BIT4
BIT3
RESET
SHDN
BIT2
BIT1
BIT0
PWRON PRXINTS AMBINTS
REGISTER
ADDRESS
0x00
POWERON
R/W
RESET
STATE
0x04
R/W
The AMBINTS bit in the Status register 0x00 is read only and indicates that an ambient light interrupt condition has
occurred. If any of these bits (PWRON, PRXINTS, AMBINTS) is set to 1, the INT pin is pulled low. The PRXINTS bit in
the Status register 0x00 is read only and indicates that a proximity receive interrupt condition has occurred. PWRON
bit in the Status register 0x00 is read only, and if set, indicates that a power-on-reset condition has occurred, and any
user-programmed thresholds may not be valid anymore. The SHDN bit in the Status register 0x00 is read/write and can
be used to put the part into and bring out of shutdown for power saving. All register data is retained during this operation. The RESET bit in the Status register 0x00 is also read/write and can be used to reset all of the registers back to
power-on default condition.
Reading the Interrupt Status register clears the PWRON, PRXINTS and AMBINTS bits, and if set, deasserts the INT pin
(INT pin is pulled high by the off-chip pullup resistor). The PRXINTS and AMBINTS bits are disabled and set to 0 if the
respective interrupt enable bits in Register 0x01 are set to 0.
Table 1. Ambient Interrupt Status Flag (AMBINTS)
BIT0
OPERATION
0
No interrupt trigger event has occurred.
1
The ambient light has exceeded the designated window limits defined by threshold registers for longer than persist
timer count AMBPST[1:0]. It also causes the INT pin to be pulled low. Once set, the only way to clear this bit is to
read this register. This bit is always set to 0 if AMBINTE bit is set to 0.
Table 2. Proximity Receive Interrupt Status Flag (PRXINTS)
BIT1
OPERATION
0
No interrupt trigger event has occurred.
1
The IR proximity receive intensity has exceeded the proximity threshold limit for longer than persist timer count
PRXPST[1:0]. It also causes the INT pin to be pulled low. Once set, the only way to clear this bit is to read this register. This bit is always set to 0 if PRXINTE bit is set to 0.
Table 3. Power-On Interrupt Status Flag (PWRON)
BIT2
OPERATION
0
Normal operating mode.
1
The part went through a power-up event, either because the part was turned on or because there was a powersupply voltage glitch. All interrupt threshold settings in the registers have been reset to power-on-default states and
should be examined if necessary. The INT pin is also pulled low. Once this bit is set, the only way to clear this bit is
to read this register.
Maxim Integrated
11
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Table 4. Shutdown Control (SHDN)
BIT3
OPERATION
0
The part is in normal operation. When the part returns from shutdown, note that the value in the data registers is not
current until first conversion cycle is completed.
1
The part can be put into a power-save mode by writing a 1 to this bit. Supply current is reduced to about 0.05FA
with no I2C clock activity. While all registers remain accessible and retain data, ADC conversion data contained in
them may not be current. Writeable registers also remain accessible in shutdown. All interrupts are cleared.
Table 5. Reset Control (RESET)
BIT4
OPERATION
0
The part is in normal operation.
1
The part undergoes a forced power-on-reset sequence. All Configuration, Threshold, and Data registers are reset to
power-on state by writing a 1 to this bit, and an internal hardware reset pulse is generated. This bit then automatically becomes 0 after the RESET sequence is completed. After resetting, the PWRON interrupt is triggered.
Main Configuration (0x01)
REGISTER
Main Configuration
BIT7
BIT6
BIT5
MODE[2:0]
BIT4
BIT3
BIT2
AMBSEL[1:0]
BIT1
BIT0
PRXINTE AMBINTE
REGISTER
ADDRESS
0x01
POWERON
R/W
RESET
STATE
0x20
R/W
Writing to the Main Configuration register does not abort any ambient or proximity data conversion (Registers 0x04 to
0x11) if already in progress. It applies the new settings during the next conversion period.
Table 6. Ambient Interrupt Enable (AMBINTE)
BIT0
OPERATION
0
The AMBINTS bit and INT pin remain unasserted even if an ambient interrupt event has occurred. The AMBINTS bit
is set to 0 if previously set to 1. See Table 1 for more details.
1
Detection of ambient interrupt events is enabled. See Table 1 for more details. An ambient interrupt can trigger a
hardware interrupt (INT pin pulled low) and set the AMBINTS bit (Register 0x00, BIT0).
Table 7. Proximity Interrupt Enable (PRXINTE)
BIT1
OPERATION
0
PRXINTS bit and INT pin remains unasserted even if a proximity interrupt event has occurred. The PRXINTS bit is set
to 0 if previously set to 1. See Table 2 for more details.
1
Detection of proximity interrupt events is enabled. See Table 2 for more details. A proximity interrupt can trigger a
hardware interrupt (INT pin pulled low) and set the PRXINTS bit (Register 0x00, BIT1).
Note: Detection of ambient interrupt event sets the AMBINTS bit (Register 0x00, BIT0) only if AMBINTE bit is set to 1. Detection of
a proximity interrupt event sets the PRXINTS bit (Register 0x00, BIT1) only if PRXINTE bit is set to 1. If either AMBINTS or PRXINTS
bits are set to 1, it pulls the interrupt INT pin low (assert it). A read of the Interrupt Status register clears both the AMBINTS and
PRXINTS bits if set to 1, and deassert the INT pin if pulled low.
Maxim Integrated
12
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Ambient Interrupt Select (AMBSEL[1:0])
The two AMBSEL[1:0] bits define four operating modes for the IC.
Table 8. Ambient Interrupt Select (AMBSEL[1:0])
AMBSEL[1:0]
OPERATION
00
CLEAR channel data is used to compare with ambient interrupt thresholds and ambient timer settings.
01
GREEN channel data is used to compare with ambient interrupt thresholds and ambient timer settings.
10
IR channel data is used to compare with ambient interrupt thresholds and ambient timer settings.
11
TEMP channel data is used to compare with ambient interrupt thresholds and ambient timer settings.
MODE[2:0]
The three MODE[2:0] bits define eight operating modes for the IC.
Table 9. MODE[2:0]
MODE[2:0]
OPERATING MODE
000
CLEAR
CLEAR + TEMP* channel active only
COMMENTS
CLEAR + TEMP* + IR channels active
001
CLEAR + IR
010
CLEAR + RGB + IR
CLEAR + TEMP* + RGB + IR channels active
011
CLEAR + IR + PROX
CLEAR + TEMP* + IR + PROX channels active
(CLEAR + TEMP* + IR + PROX interleaved)
100
CLEAR + RGB + IR + PROX
101
PROX only
PROX only continuous
110
Reserved
Reserved
111
Reserved
Reserved
CLEAR + TEMP* + RGB + IR + PROX channels active
(CLEAR + TEMP* + RBG + IR and PROX interleaved)
*When TEMPEN is set to 1.
Ambient Configuration Register (0x02)
REGISTER
Ambient Configuration
BIT7
BIT6
BIT5
TRIM
COMPEN
TEMPEN
BIT4
BIT3
BIT2
AMBTIM[2:0]
BIT1
BIT0
AMBPGA[1:0]
REGISTER
ADDRESS
0x02
POWERON
R/W
RESET
STATE
0x00
R/W
Writing to the Ambient Configuration register aborts any ambient data conversion (Registers 0x04 to 0x0F) if already in
progress, applies the new settings immediately, and initiates a new conversion.
Maxim Integrated
13
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
AMBPGA[1:0]
The two AMBPGA[1:0] bits set the gain of the clear/red/green/blue/IR channel measurements according to Table 10.
Table 10. AMBPGA[1:0]
In AMBTIM[2:0] = 000 mode (100ms integration time).
CLEAR
AMBPGA[1:0]
nW/cm2 per
LSB*
RED
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
GREEN
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
00
2
32.768
2
32.768
2
32.768
01
8
131.072
8
131.072
8
131.072
10
11
32
512
524.288
8388.61
32
512
524.288
8388.61
32
512
524.288
8388.61
AMBPGA[1:0]
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
4
65.536
2
32.768
BLUE
00
IR
01
16
262.144
8
131.072
10
64
1048.573
32
524.288
11
1024
16777.2
512
8388.61
In AMBTIM[2:0] = 100 mode (400ms integration time).
CLEAR
AMBPGA[1:0]
00
nW/cm2 per
RED
GREEN
LSB*
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
0.5
8.192
0.5
8.192
0.5
8.192
01
2
32.768
2
32.768
2
32.768
10
11
8
128
131.072
2097.153
8
128
131.072
2097.153
8
128
131.072
2097.153
AMBPGA[1:0]
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
00
1
16.384
0.5
8.192
BLUE
IR
01
4
65.536
2
32.768
10
16
262.1433
8
131.072
11
256
4194.3
128
2097.153
*At 14-bit resolution, 100ms ADC conversion time. Sensitivity is four times higher with 400ms integration time.
Maxim Integrated
14
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
AMBTIM[2:0]
The three AMBTIM[2:0] bits set the integration time for the red/green/blue/IR/temp channel ADC conversion.
Table 11. AMBTIM[2:0]
AMBTIM[2:0]
INTEGRATION TIME
(ms)
FULL-SCALE ADC
(Counts)
BIT RESOLUTION
RELATIVE LSB
SIZE FOR FIXED
AMBPGA[1:0]
000
100
16,384
14
1x
001
25
4,096
12
4x
010
6.25
1,024
10
16x
011
1.5625
256
8
64x
100
400
16,384
14
1/4x
101
Reserved
Not applicable
Not applicable
Not applicable
110
Reserved
Not applicable
Not applicable
Not applicable
111
Reserved
Not applicable
Not applicable
Not applicable
TEMPEN
Table 12. TEMPEN
BIT 6
OPERATION
0
Disables temperature sensor.
1
Enables temperature sensor.
The integration time of temperature sensor is controlled by the ambient mode settings. The temperature sensor is
enabled only if the clear channel is on.
COMPEN
Table 13. COMPEN
BIT 5
OPERATION
0
Disables IR compensation.
1
Enables IR compensation. Only for MODE[2:0] = 000 mode.
The integration time of compensation channel is controlled by the ambient mode settings. The compensation is enabled
only when the clear channel is on. When COMPEN = 1, the CLEAR data is automatically compensated for stray IR
leakage and temperature variations. When COMPEN = 0, the IR compensation is disabled, but the output of the IR
compensation data exists.
Table 14. Trim Adjust Enable (TRIM)
BIT 7
OPERATION
0
Use factory-programmed gains for all the channels. Ignore any bytes written to the TRIM_GAIN_GREEN[6:0], TRIM_
GAIN_RED[6:0], TRIM_GAIN_BLUE[6:0], TRIM_GAIN_CLEAR[6:0], and TRIM_GAIN_IR[6:0] registers.
1
Use bytes written to the TRIM_GAIN_GREEN[6:0], TRIM_GAIN_RED[6:0], TRIM_GAIN_BLUE[6:0], TRIM_GAIN_
CLEAR[6:0], and TRIM_GAIN_IR[6:0] registers to set the gain for each channel.
Maxim Integrated
15
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Proximity Configuration Register (0x03)
REGISTER
Proximity Configuration
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
DRV[3:0]
BIT1
REGISTER
ADDRESS
BIT0
PRXTIM PRXPGA
POWERON
R/W
RESET
STATE
0x03
0x00
R/W
Writing to the Proximity Configuration register aborts any proximity data conversion (Registers 0x10 and 0x11) if already
in progress, and applies the new settings immediately.
PRXPGA
The PRXPGA sets the gain of the IR channel in proximity mode measurement according to Table 15.
Table 15. PRXPGA
BIT0
µW/cm2 per LSB*
FULL SCALE (µW/cm2)
0
2
2095
1
16
16,777
*At 14-bit resolution, 100ms ADC conversion time.
PRXTIM
The PRXTIM sets the integration time for IR channel ADC in proximity mode as shown in Table 16.
Table 16. PRXTIM
BIT1
ADC CONVERSION TIME (ms)
FULL-SCALE ADC (Counts)
BIT RESOLUTION
0
6.25
1024
10
1
1.5625
256
8
DRV[3:0]
The four bits of DRV set the LED drive current.
Table 17. DRV[3:0]
DRV[3:0]
LED CURRENT (mA)
DRV[3:0]
LED CURRENT (mA)
0000
LED driver disabled
0110
60
0001
10
0111
70
0010
20
1000
80
0011
30
1001
90
0100
40
1010
100
0101
50
1011-1111
110
Maxim Integrated
16
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
AMBIENT Data Register (0x04–0x0F)
REGISTER
BIT7
BIT6
—
—
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
REGISTER
ADDRESS
POWERON
R/W
RESET
STATE
AMBIENT READING
Ambient CLEAR High Byte
AMB_CLEAR[13:8]
Ambient CLEAR Low Byte
Ambient RED High Byte
AMB_CLEAR[7:0]
—
—
—
—
AMB_RED[13:8]
Ambient RED Low Byte
Ambient GREEN High Byte
AMB_RED[7:0]
AMB_GREEN[13:8]
Ambient GREEN Low Byte
Ambient BLUE High Byte
AMB_GREEN[7:0]
—
—
AMB_BLUE[13:8]
Ambient BLUE Low Byte
Ambient INFRARED High
Byte
AMB_BLUE[7:0]
—
—
—
—
AMB_IR[13:8]
Ambient INFRARED Low Byte
Ambient IR COMP High Byte
AMB_IR[7:0]
AMB_IRCOMP[13:8]
Ambient IR COMP Low Byte
AMB_IRCOMP[7:0]
0x04
0x00
R
0x05
0x00
R
0x06
0x00
R
0x07
0x00
R
0x08
0x00
R
0x09
0x00
R
0x0A
0x00
R
0x0B
0x00
R
0x0C
0x00
R
0x0D
0x00
R
0x0E
0x00
R
0x0F
0x00
R
The 12 registers here hold the results of ADC. AMB_CLEAR[13:0], AMB_RED[13:0], AMB_GREEN[13:0],
AMB_BLUE[13:0], AMB_IR[13:0], and AMB_IRCOMP[13:0] hold the 14-bit ADC data of the clear/red/green/blue/IR/
COMP channels. AMB_IRCOMP[13:0] can be used to enhance overtemperature performance of the device. The
resolution and bit length of the result is controlled by the value of AMBTIM[2:0] and AMBPGA[1:0] bits. The result is
always right justified in registers, and the unused high bits are set to zero.
Proximity Data Register (0x10, 0x11)
REGISTER
PROXIMITY IR High Byte
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
—
—
—
—
—
—
PROXIMITY IR Low Byte
BIT1
BIT0
PROX[9:8}
PROX[7:0]
POWERREGISTER
ON
R/W
ADDRESS RESET
STATE
0x10
0x00
R
0x11
0x00
R
The two bytes here (PROX[9:0]) hold the results of the proximity receive signal conversion. The resolution and bit length
of the result is controlled by the value of the PRXTIM bits. The result is always right justified in the two registers, and
the unused high bits are set to zero.
Temperature Data Register (0x12–0x13)
REGISTER
TEMP High Byte
TEMP Low Byte
BIT7
BIT6
—
—
BIT5
BIT4
BIT3
BIT2
TEMP[13:8]
TEMP[7:0]
BIT1
BIT0
REGISTER
ADDRESS
POWERON
R/W
RESET
STATE
0x12
0x00
R
0x13
0x00
R
These two bytes hold the data of the temperature sensor.
Maxim Integrated
17
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Ambient Interrupt Threshold Registers (0x14–0x17)
REGISTER
BIT7
BIT6
AMB Upper Threshold—High
Byte
—
—
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
UPTHR[13:8]
AMB Upper Threshold—Low
Byte
UPTHR[7:0]
AMB Lower Threshold—High
Byte
—
—
LOTHR[13:8]
AMB Lower Threshold—Low
Byte
LOTHR[7:0]
REGISTER
ADDRESS
POWERON
R/W
RESET
STATE
0x14
0x00
R/W
0x15
0x00
R/W
0x16
0x00
R/W
0x17
0x00
R/W
The Ambient Upper Threshold and Lower Threshold register bits (UPTHR[13:0] and LOTHR[13:0], respectively) set
the window limits that are used to trigger an ambient interrupt, AMBINTS. It is important to set these values according
to the selected bit resolution/integration time chosen for the ambient measurement based on the AMBTIM[2:0] and
AMBPGA[1:0] settings. The upper two bits are always ignored. If the AMBINTE bit is set, and the selected ambient
channel data is outside the upper or lower thresholds for a period greater than that defined by the AMBPST persist time,
the AMBINTS bit in the Status register are set and INT pin is pulled low.
AMB/PROX Threshold Persist Timer Register (0x18)
REGISTER
BIT7
BIT6
BIT5
BIT4
—
—
—
—
Threshold Persist Timer
BIT3
BIT2
PRXPST[1:0]
BIT1
BIT0
AMBPST[1:0]
REGISTER
ADDRESS
0x18
POWERON
R/W
RESET
STATE
0x00
R/W
PRXPST[1:0] and AMBPST[1:0] set one of four persist values in Table 18 that control a time-delay before the interrupt
logic reacts to a detected event. This feature is added to reduce false or nuisance interrupts.
Table 18. PRXPST[1:0]/AMBPST[1:0]
PRXPST[1:0] or AMBPST[1:0]
NO. OF CONSECUTIVE MEASUREMENTS REQUIRED TO
TRIGGER AN INTERRUPT
00
1
01
4
10
8
11
16
When AMBPST[1:0] is set to 00 and the AMBINTE bit is set to 1, the first time an AMB interrupt event is detected, the
AMBINTS interrupt bit is set and the INT pin goes low. If AMBPST[1:0] is set to 01, then four consecutive interrupt events
must be detected on four consecutive measurement cycles. Similarly, if AMBPST[1:0] is set to 10 or 11, then 8 or 16
consecutive interrupt events must be detected. If there is an intervening measurement cycle where no interrupt event is
detected, then the count is reset to zero. The proximity interrupt function is managed in the same way with PRXPST[1:0].
Maxim Integrated
18
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Proximity Threshold Registers (0x19–0x1C)
REGISTER
PROX Upper Threshold—
High Byte
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
—
—
—
—
—
—
PROX Upper Threshold—Low
Byte
PROX Lower Threshold—
High Byte
BIT1
BIT0
PRXUPTHR[9:8]
PRXUPTHR[7:0]
—
—
—
PROX Lower Threshold—Low
Byte
—
—
—
PRXLOTHR[9:8]
PRXLOTHR[7:0]
REGISTER
ADDRESS
POWERON
R/W
RESET
STATE
0x19
0xFF
R/W
0x1A
0xFF
R/W
0x1B
0x00
R/W
0x1C
0x00
R/W
The proximity upper and lower thresholds (PRXUPTHR[9:0] and PRXLOTHR[9:0], respectively) set the window limits
that are used to trigger a proximity interrupt, and PRXINTS is set. It is important to set these values according to the
selected bit resolution/integration time chose for the PRXTIM measurement based on the PRXTIM and PRXPGA settings.
If the PRXINTE bit is set, and the proximity channel data is outside the upper or lower thresholds for a period greater
than that defined by the PRXPST persist time, the PRXINTS bit in the Status register is set and the INT pin is pulled low.
Gain Trim Registers (0x1D–0x21)
TRIM_GAIN_CLEAR is used to trim the gain of the clear channel.
REGISTER
Digital Gain Trim of CLEAR
Channel
Digital Gain Trim of RED
Channel
Digital Gain Trim of GREEN
Channel
Digital Gain Trim of BLUE
Channel
Digital Gain Trim of
INFRARED Channel
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
REGISTER
ADDRESS
POWERON
R/W
RESET
STATE
TRIM_GAIN_CLEAR[6:0]
0x1D
0xXX
R/W
TRIM_GAIN_RED[6:0]
0x1E
0xXX
R/W
TRIM_GAIN_GREEN[6:0]
0x1F
0xXX
R/W
TRIM_GAIN_BLUE[6:0]
0x20
0xXX
R/W
TRIM_GAIN_IR[6:0]
0x21
0xXX
R/W
TRIM_GAIN_RED is used to trim the gain of the red channel. TRIM_GAIN_GREEN is used to trim the gain of the green
channel. TRIM_GAIN_BLUE is used to trim the gain of the blue channel. TRIM_GAIN_IR is used to trim the gain of the IR
channel. These registers are loaded with the factory trimmed gains on power-up. When the TRIM bit in Register 0x02 is
set to 1, these registers can be overwritten with user-chosen gains. When the TRIM bit is set back to 0, these registers
are automatically reloaded with factory-trimmed values.
Maxim Integrated
19
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Applications Information
property of attenuating most ambient light, but passing
through infrared radiation.
Ambient Sensing Applications
It is possible to map the RGB color values to an XY coordinate system for ambient color temperature and color
gamut display.
Typical applications involve placing the IC behind glass
with a small semi-transparent window placed above it.
Use the photodiode sensitive area as shown in Figure 2
to properly position the window above the part.
Proximity Sensing Applications
The IC integrates a novel proximity sensor interface
circuit with a robust built-in ambient IR cancellation
scheme. The internal DC IR rejection circuit eliminates
problems of ADC saturation in the presence of strong
ambient infrared radiation, such as bright sunlight.
Further, the proximity sensor uses a single-pulse scheme
for the IR transmitter that eliminates red-glow problems
seen in competing solutions to drive 850nm IR LEDs,
while also reducing average IR LED power consumption
to less than 0.01% of the IR LED peak current.
The part comes equipped with Internal Gain Trim registers for the CLEAR, RGB, and IR AMB photodiodes. By
suitably choosing the gains for these channels, one can
generate accurate ambient light readings in all lighting
conditions irrespective of type of glass the part is used
under. This is especially useful for color-glass applications where for cosmetic reasons the part is placed
behind a color film to hide its presence and to blend
with the product cosmetic look. This film has the peculiar
2000µm
750µm
490µm
750µm
350µm
6
1
IR SENSOR
160µm
130µm
650µm
2
300µm
185µm
3
B
C
R
G
R
G
B
B+R
G
B
C
R
C
B+R
G
B
G
R
B
C
R
C
B+R
G
B
G
R
C
B+R
R
C
B
C
B
G
R
5
2000µm
4
MAX44005
285µm
610µm
240µm
Figure 2. Photodiode Location
Maxim Integrated
20
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Interrupt Operation
Ambient interrupt is enabled by setting bit 0 of Register
0x01 to 1 and proximity interrupt is enabled by setting bit
1 of Register 0x01 to 1 (see Tables 6 and 7). The interrupt
pin, INT, is an open-drain output and pulls low when an
interrupt condition occurs (e.g., when ambient lux readings exceed threshold limits for a period greater than that
set by the persist timer register). The interrupt status bit
is cleared automatically if Register 0x00 is read or if the
interrupts are disabled.
A PWRON interrupt bit is set to alert the master of a chip
reset operation in case of a power-supply glitch, which
can happen on smartphones that place the light sensor
on a flex with a small connector.
It is recommended to utilize the interrupt pin on the IC to
alert the master to come and read measurements from
the IC. This eliminates the need for the microcontroller
(I2C master) to continually poll the device for information.
Due to the use of pullup resistors on the I2C bus, minimizing I2C bus activity can reduce power consumption
substantially. In addition, this frees up the microcontroller
resources to service other background processes to
improve device performance. The wide variety of smarts
available on the chip, such as ability to set the threshold
levels and to count persist timer limits, allow the part to
operate in an autonomous mode most of the time.
Typical Operating Sequence
Here is the typical operating sequence for the master to
communicate to the IC:
A. Setup:
1) Read the Interrupt Status register (0x00) to confirm
only the PWRON bit is set (usually at power-up
only). This also clears a hardware interrupt.
2) Set the Threshold and Persist Timer registers for
ambient and proximity sensor measurements.
3) Write 0x01 to Proximity Configuration register
(Register 0x03) to set the proximity sensor in the
lowest gain setting, AMB sensor in the highest gain
setting, and the PROX and AMB ADCs are in 10-bit
and 14-bit modes separately.
4) Set IR LED current to suitable level by writing to the
Transmit Configuration register (0x03).
5) Write 0x43 to Main Configuration register (Register
0x01) to set the part in RGBC + IR + PROX
mode, and to enable AMB and proximity interrupts.
Ensure RGBC + IR + PROX mode is enabled.
6) Set new CLEAR, RGB, and infrared channel gains
if necessary to customize AMB operation for application conditions. Ensure TRIM bit is set to 1 when
not using default factory-trim settings. Otherwise,
keep this bit set to 0 (power-on default state).
B. Wait for interrupt.
C. On interrupt:
1) Read the Interrupt Status register (0x00) to confirm
the IC to be source of interrupt and to check for
type of interrupt. This should clear the hardware
interrupt on the part, if set.
2) If an AMB interrupt has occurred, read AMB
registers (Register 0x04-0x0D) to confirm if data is
valid, and take appropriate action (e.g., sets
new backlight strength). Set new AMB thresholds if
necessary.
3) If a PROX interrupt has occurred, read the PROX
IR registers (Registers 0x10-0x11) and take
appropriate action (typically turn off or turn on
touch screen and backlight). Set new proximity
thresholds if necessary.
4) Return to step B.
I2C Serial Interface
The IC features an I2C/SMBus-compatible, 2-wire serial
interface consisting of a serial-data line (SDA) and a
serial-clock line (SCL). SDA and SCL facilitate communication between the IC and the master at clock rates
up to 400kHz. Figure 3 shows the 2-wire interface timing
diagram. The master generates SCL and initiates data
Table 19. Slave Address
SLAVE ADDRESS FOR WRITING
SLAVE ADDRESS FOR READING
1000 1000
1000 1001
Maxim Integrated
21
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
transfer on the bus. A master device writes data to the
IC by transmitting the proper slave address followed by
the register address and then the data word. Each transmit sequence is framed by a START (S) or REPEATED
START (Sr) condition and a STOP (P) condition. Each
word transmitted to the IC is 8 bits long and is followed
by an acknowledge clock pulse. A master reading data
from the IC transmits the proper slave address followed
by a series of nine SCL pulses. The IC transmits data on
SDA in sync with the master-generated SCL pulses. The
master acknowledges receipt of each byte of data. Each
read sequence is framed by a START or REPEATED
START condition, a not acknowledge, and a STOP condition. SDA operates as both an input and an open-drain
output. A pullup resistor, typically greater than 500I, is
required on the SDA bus. SCL operates as only an input.
A pullup resistor, typically greater than 500I, is required
on SCL if there are multiple masters on the bus, or if the
master in a single-master system has an open-drain SCL
output. Series resistors in line with SDA and SCL are
optional. Series resistors protect the digital inputs of the
IC from high-voltage spikes on the bus lines, and minimize crosstalk and undershoot of the bus signal.
Bit Transfer
One data bit is transferred during each SCL cycle. The
data on SDA must remain stable during the high period
of the SCL pulse. Changes in SDA while SCL is high are
control signals. See the START and STOP Conditions section. SDA and SCL idle high when the I2C bus is not busy.
START and STOP Conditions
SDA and SCL idle high when the bus is not in use. A master initiates communication by issuing a START condition.
A START condition is a high-to-low transition on SDA with
SCL high. A STOP condition is a low-to-high transition on
SDA while SCL is high (Figure 4). A START condition from
the master signals the beginning of a transmission to the
IC. The master terminates transmission and frees the bus
by issuing a STOP condition. The bus remains active if
a REPEATED START condition is generated instead of a
STOP condition.
SDA
tBUF
tSU, STA
tSU, DAT
tHD, STA
tHD, DAT
tLOW
tSP
tSU, STO
SCL
tHIGH
tHD, STA
tR
tF
REPEATED
START CONDITION
START
CONDITION
STOP
CONDITION
START
CONDITION
Figure 3. 2-Wire Interface Timing Diagram
S
Sr
CLOCK PULSE FOR
ACKNOWLEDGMENT
P
SCL
START
CONDITION
SCL
1
2
8
9
NOT ACKNOWLEDGE
SDA
SDA
ACKNOWLEDGE
Figure 4. START, STOP, and REPEATED START Conditions
Maxim Integrated
Figure 5. Acknowledge
22
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Early STOP Conditions
cycle to acknowledge receipt of data when the IC is in
read mode. An acknowledge is sent by the master after
each read byte to allow data transfer to continue. A not
acknowledge is sent when the master reads the final byte
of data from the IC, followed by a STOP condition.
Acknowledge
A write to the IC includes transmission of a START condition, the slave address with the R/W bit set to 0, one byte
of data to configure the internal register address pointer,
one or more bytes of data, and a STOP condition. Figure
6 illustrates the proper frame format for writing one byte
of data to the IC. Figure 7 illustrates the frame format for
writing n-bytes of data to the IC.
The IC recognizes a STOP condition at any point during
data transmission except if the STOP condition occurs in
the same high pulse as a START condition. For proper
operation, do not send a STOP condition during the same
SCL high pulse as the START condition.
The acknowledge bit (ACK) is a clocked ninth bit that the
IC uses to handshake receipt each byte of data when in
write mode (Figure 5). The IC pulls down SDA during the
entire master-generated ninth clock pulse if the previous
byte is successfully received. Monitoring ACK allows for
detection of unsuccessful data transfers. An unsuccessful data transfer occurs if a receiving device is busy or if a
system fault has occurred. In the event of an unsuccessful data transfer, the bus master may retry communication. The master pulls down SDA during the ninth clock
Write Data Format
The slave address with the R/W bit set to 0 indicates
that the master intends to write data to the IC. The IC
acknowledge receipt of the address byte during the
master-generated ninth SCL pulse.
ACKNOWLEDGE FROM MAX44005
B7
ACKNOWLEDGE FROM MAX44005
SLAVE ADDRESS
S
B6
B5
B4
B3
B2
B1
B0
ACKNOWLEDGE FROM MAX44005
0
A
REGISTER ADDRESS
A
DATA BYTE
A
R/W
P
1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
Figure 6. Writing 1 Byte of Data to the IC
ACKNOWLEDGE FROM MAX44005
ACKNOWLEDGE FROM MAX44005
ACKNOWLEDGE FROM MAX44005
S
SLAVE ADDRESS
0
A
REGISTER ADDRESS
R/W
B7 B6 B5 B4 B3 B2 B1 B0
B7 B6 B5 B4 B3 B2 B1 B0
ACKNOWLEDGE FROM MAX44005
A
DATA BYTE 1
A
1 BYTE
DATA BYTE n
A
P
1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
Figure 7. Writing n-Bytes of Data to the IC
Maxim Integrated
23
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
The second byte transmitted from the master configures
the IC’s internal register address pointer. The pointer tells
the IC where to write the next byte of data. An acknowledge pulse is sent by the IC upon receipt of the address
pointer data.
within one continuous frame. A STOP condition can be
issued after any number of read data bytes. If a STOP
condition is issued followed by another read operation,
the first data byte to be read is from Register 0x00 and
subsequent reads autoincrement the address pointer
until the next STOP condition. The address pointer can
be preset to a specific register before a read command
is issued. The master presets the address pointer by first
sending the IC’s slave address with the R/W bit set to 0
followed by the register address. A REPEATED START
condition is then sent followed by the slave address with
the R/W bit set to 1. The IC transmits the contents of the
specified register. The address pointer autoincrements
after transmitting the first byte. Attempting to read from
register addresses higher than 0xFF results in repeated
reads of 0xFF. Note that 0xF6 to 0xFF are reserved registers. The master acknowledges receipt of each read byte
during the acknowledge clock pulse. The master must
acknowledge all correctly received bytes except the last
byte. The final byte must be followed by a not acknowledge from the master and then a STOP condition. Figure
8 illustrates the frame format for reading one byte from
the IC. Figure 9 illustrates the frame format for reading
multiple bytes from the IC.
The third byte sent to the IC contains the data that is
written to the chosen register. An acknowledge pulse
from the IC signals receipt of the data byte. The address
pointer autoincrements to the next register address after
each received data byte. This autoincrement feature
allows a master to write to sequential registers within one
continuous frame. Figure 8 illustrates how to write to multiple registers with one frame. The master signals the end
of transmission by issuing a STOP condition.
Read Data Format
Send the slave address with the R/W bit set to 1 to initiate a read operation. The IC acknowledges receipt of its
slave address by pulling SDA low during the ninth SCL
clock pulse. A START command followed by a read command resets the address pointer to Register 0x00. The
first byte transmitted from the IC is the content of Register
0x00. Transmitted data is valid on the rising edge of the
master-generated serial clock (SCL). The address pointer
autoincrements after each read data byte. This autoincrement feature allows all registers to be read sequentially
NOT ACKNOWLEDGE FROM MASTER
ACKNOWLEDGE FROM MAX44005
ACKNOWLEDGE FROM MAX44005
S
SLAVE ADDRESS
0
A
REGISTER ADDRESS
ACKNOWLEDGE FROM MAX44005
A
Sr
SLAVE ADDRESS
REPEATED START
R/W
1
R/W
A
DATA BYTE
A
P
1 BYTE
AUTO-INCREMENT INTERNAL
REGISTER ADDRESS POINTER
Figure 8. Reading One Indexed Byte of Data from the IC
ACKNOWLEDGE FROM MAX44005
ACKNOWLEDGE FROM MAX44005
S
SLAVE ADDRESS
0
R/W
A
REGISTER ADDRESS
ACKNOWLEDGE FROM MAX44005
A
REPEATED START
Sr
SLAVE ADDRESS
1
R/W
A
DATA BYTE
A
P
1 BYTE
AUTO-INCREMENT INTERNAL
REGISTER ADDRESS POINTER
Figure 9. Reading n-Bytes of Indexed Data from the IC
Maxim Integrated
24
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Typical Application Circuit
VLED =
1.7V TO 5.5V
1.7V TO 2V
1.4V TO 5.5V
1µF
10kI
10kI
10kI
VCC
SDA
SDA
GND
SCL
SCL
DRV
INT
INT
MAX44005
SDA
SDA
SCL
SCL
I2C SLAVE_1
I2C SLAVE_n
MICROCONTROLLER
2
(I C MASTER)
Ordering Information
PART
PIN-PACKAGE
TEMP RANGE
MAX44005EDT+
6 OTDFN
-40NC to +85NC
+Denotes a lead(Pb)-free/RoHS-compliant package.
Maxim Integrated
25
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Package Information
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the
drawing pertains to the package regardless of RoHS status.
PACKAGE TYPE
PACKAGE CODE
OUTLINE
NO.
LAND
PATTERN NO.
6 OTDFN
D622CN+1
21-0606
90-0376
Maxim Integrated
26
MAX44005
RGB Color, Temperature,
and Infrared Proximity Sensor
Revision History
REVISION
NUMBER
REVISION
DATE
0
5/12
Initial release
10/12
Updated Absolute Maximum Ratings section, changed second occurrence of
ADC Conversion Time to Accuracy Conversion Accuracy, added note in Electrical
Characteristics table, replaced TOC 4, removed sentence from Register Description
section
1
DESCRIPTION
PAGES
CHANGED
—
2–5, 11
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent
licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and
max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000
© 2012 Maxim Integrated Products, Inc.
27
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
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