EVALUATION KIT AVAILABLE
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
General Description
The MAX44006/MAX44008 integrate six sensors in two
products: red, green, blue (RGB) sensors; an ambient
light (clear) sensor; a temperature sensor; and an ambient infrared sensor with an I2C interface. These highly
integrated optical sensors include a temperature sensor
to improve reliability and performance.
The devices compute the light information with six parallel data converters allowing simultaneous light measurement in a very short time. The devices consume only
15FA (MAX44006) and 16FA (MAX44008) separately in
RGBC + TEMP + IR mode, and also have the ability to
operate at 1.7V to 2.0V (MAX44006) and 2.7V to 5.5V
supply voltage (MAX44008).
The devices’ RGB sensing capability improves the
performance of end products by providing robust and
precise information for ambient color-sensing and
color-temperature measurement.
The devices’ superior infrared and 50Hz/60Hz rejection
provide robust readings. The wide dynamic range light
measurement makes these products perfect candidates
for many color measurement applications.
The on-chip ambient sensor has the ability to make wide
dynamic range (0.002~8388.61FW/cm2) lux measurements. The devices’ digital computation power provides
programmability and flexibility for end-product design. A
programmable interrupt pin minimizes the need to poll
the devices for data, freeing up microcontroller resources, reducing system software overhead, and ultimately
reducing power consumption. All these features are
included in a tiny 2mm x 2mm x 0.6mm optical package.
Applications
Features
S Optical Sensor Fusion for True Color Sensing
Seven Parallel ADCs
R, G, B, IR, ALS Sensing
S Superior Sensitivity
0.001 Lux
S Optimized for Overall System Power Consumption
10µA (MAX44006)/10µA (MAX44008) in Ambient
Mode
15µA (MAX44006)/16µA (MAX44008) in RGBC +
IR Mode
0.01µA (MAX44006)/0.5µA (MAX44008) in
Shutdown Mode
S Digital Functionalities
Programmable Channel Gains
Adjustable Interrupt Thresholds
S High-Level Integration
Six Sensors in a 2mm x 2mm x 0.6mm
Package
Functional Diagram
VDD
MAX44006
MAX44008
RED
AMB
PGA
14-BIT
ADC
SDA
GREEN
BLUE
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
TVs/Display Systems
Tablet PCs/Notebooks/e-Readers
COMP
Digital Light Management
Industrial Sensors
IR
Tablets
Color Correction
TEMP
Ordering Information appears at end of data sheet.
For related parts and recommended products to use with this part,
refer to www.maximintegrated.com/MAX44006.related.
MICROCONTROLLER
I2C
CLEAR
Printers
LED and Laser Projectors
SCL
GND
INT
14-BIT
ADC
GND
AO
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-6298; Rev 1; 8/12
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
ABSOLUTE MAXIMUM RATINGS
VDD to GND (MAX44006).....................................-0.3V to +2.2V
VDD to GND (MAX44008) ....................................-0.3V to +6.0V
A0, INT, SCL, SDA to GND...................................-0.3V to +6.0V
Output Short-Circuit Current Duration........................Continuous
Continuous Input Current into Any Terminal.................... Q20mA
Continuous Power Dissipation
(derate 11.9mW/NC above +70NC)...............................953mW
Operating Temperature Range........................... -40NC to +85NC
Soldering Temperature (reflow).......................................+260NC
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.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
OTDFN (Note 1)
Junction-to-Ambient Thermal Resistance (BJA)..…+83.9°C/W
Junction-to-Case Thermal Resistance (BJC)............. +37°C/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.
ELECTRICAL CHARACTERISTICS
(VDD = 1.8V (MAX44006), VDD = 3.3V (MAX44008), TA = +25NC, min/max are from -40°C to +85°C, 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
Dark-Level Counts
ADC Conversion Time
Maxim Integrated
FW/cm2
FW/cm2
16,777
8388
Power = 10FW/cm2, red = 630nm,
green = 538nm, blue = 470nm,
TA = +25NC, clear = 538nm, IR = 850nm
2
15
%
Red to green to blue, TA = +25NC
0.5
10
%
tON
10
ms
2
6.25ms conversion time, 0 lux, TA = +25NC
14-bit resolution (Note 4)
400
14-bit resolution, TA = +25NC
100
12-bit resolution
25
10-bit resolution
6.25
8-bit resolution
1.5625
Counts
ms
2
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 1.8V (MAX44006), VDD = 3.3V (MAX44008), TA = +25NC, min/max are from -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
ADC Conversion Accuracy
CONDITIONS
MIN
TYP
MAX
TA = +25NC
1
10
TA = -40NC to +85NC (Note 5)
2
15
TA = +25NC~+55NC
±1
±3
±2
0.25
±5
UNITS
%
TEMPERATURE SENSOR
Accuracy (Note 5)
TA = 0NC~+70NC
Resolution
NC
NC/LSB
POWER SUPPLY
Power-Supply Voltage
Quiescent Current
Software Shutdown Current
VDD
IDD
ISHDN
MAX44006, guaranteed by total error
1.7
2
MAX44008, guaranteed by total error
2.7
5.5
MAX44006, CLEAR mode
10
18
MAX44006, RGBC + IR mode
15
30
MAX44008, CLEAR mode
10
18
MAX44008, RGBC + IR mode
16
30
MAX44006, TA = +25NC
1
MAX44008, TA = +25NC
1.5
DIGITAL CHARACTERISTICS—SDA, INT, A0
ISINK = 6mA
Output Low Voltage SDA
VOL
I2C Input Voltage High
I2C Input Voltage Low
Input Hysteresis
Input Capacitance
Input Leakage Current
VIH
SDA, SCL, A0
VIL
SDA, SCL, A0
0.4
1.4
CIN
IIN
200
FA
FA
V
V
0.4
VHYS
V
V
mV
10
pF
VIN = 0V, TA = +25NC
0.1
VIN = 5.5V, TA = +25NC
0.1
FA
I2C TIMING CHARACTERISTICS (Note 6)
0
400
kHz
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
tHIGH
0.6
Fs
tSU.STA
0.6
Fs
High Period of the SCL Clock
Setup Time for a Repeated START
Setup Time for STOP Condition
tSU,STO
0.6
Data Hold Time
tHD,DAT
0
Data Setup Time
tSU,DAT
Bus Capacitance
CB
Maxim Integrated
Fs
0.9
100
Fs
ns
400
pF
3
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
ELECTRICAL CHARACTERISTICS (continued)
(VDD = 1.8V (MAX44006), VDD = 3.3V (MAX44008), TA = +25NC, min/max are from -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
SDA and SCL Receiving Rise
Time
tR
20 +
0.1CB
300
ns
SDA and SCL Receiving Fall
Time
tF
20 +
0.1CB
300
ns
SDA Transmitting Fall Time
tf
20 +
0.1CB
250
ns
tSP
0
50
ns
Pulse Width of Suppressed Spike
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
100% production tested at TA = +25NC. 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 4 times higher with 400ms integration time than 100ms integration time.
Production tested only at +25NC, guaranteed by bench characterization across temperature.
Design guidance only, not production tested.
Typical Operating Characteristics
(VDD = 1.8V (MAX44006), VDD = 3.3V (MAX44008), TA = +25NC, min/max are from -40°C to +85°C, unless otherwise noted.)
SPECTRUM OF LIGHT SOURCES
FOR MEASUREMENT
8,000
6,000
4,000
120
100
60
40
20
0
0
WAVELENGTH (nm)
Maxim Integrated
SUNLIGHT
80
2,000
250 350 450 550 650 750 850 950 1050
INCANDESCENT
MAX44006/08 toc03
140
RADIATION PATTERN
100
NORMALIZED COUNTS (%)
COUNTS
10,000
CLEAR
RED
GREEN
BLUE
IR
160
MAX44006/08 toc02
12,000
COMPENSATION DISABLED
POWER DENSITY 15.83 µW/cm2
AMBPGA [1:0] = 00
AMBTIM[2:0] = 000
NORMALIZED RESPONSE
14,000
MAX44006/08 toc01
WAVELENGTH vs. COUNTS
80
60
CLEAR CHANNEL
AMBPGA [1:0]= 00
AMBTIM [2:0] =000
40
20
FLUORESCENT
300
400
500 600 700 800
WAVELENGTH (nm)
900 1000
0
PARALLEL TO DIP PINS DIRECTION
PERPENDICULAR TO DIP PINS DIRECTION
-90 -70 -50 -30 -10 10
30
50
70
90
ANGLE OF INCIDENCE IN DEGREE
4
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Typical Operating Characteristics (continued)
(VDD = 1.8V (MAX44006), VDD = 3.3V (MAX44008), TA = +25NC, min/max are from -40°C to +85°C, unless otherwise noted.)
500,000
400,000
300,000
150,000
125,000
100,000
0
CLEAR CHANNEL
IR CHANNEL
25,000
MAX44006/08 toc06
200,000
TEST CONDITIONS:
WHEN THE COUNT READINGS IN ONE
PGA SETTING ARE SATURATED,
CHANGE PGA SETTING TO THE
LOWER SENSITIVITY PGA
GAIN SETTING.
EX: PGA [1:0] =00 ->
PGA [1:0] = 01
150,000
100,000
50,000
0
0 100 200 300 400 500 600 700 800 900 1000
BLUE CHANNEL RESPONSE vs. BLUE LED
0
0 100 200 300 400 500 600 700 800 900 1000
50 100 150 200 250 300 350 400 450
0
POWER DENSITY (µW/cm2)
CLEAR CHANNEL RESPONSE TO WHITE LED
SUPPLY CURRENT vs. TEMPERATURE
(MAX44006)
SUPPLY CURRENT vs. TEMPERATURE
(MAX44008)
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
100
10
15
10
CLEAR
CLEAR+IR
CLEAR+RGB+IR
5
TEST CONDITION:
AMBTIM[2:0] = 000
1
10
100
1,000
20
40
60
80
CLEAR AT 2.7VDD
CLEAR + IR AT 2.7VDD
CLEAR + RGB + IR AT 2.7VDD
CLEAR AT 5.5VDD
CLEAR + IR AT 5.5VDD
CLEAR + RGB + IR AT 5.5VDD
5
0
100
-40
-20
0
20
40
60
80
100
TEMPERATURE SENSOR READINGS
vs. TEMPERATURE
MAX44006/08 toc09
TEST CONDITIONS:
CLEAR + RGB + IR MODE
LIGHT SOURCE: SUNLIGHT
VDD = 1.8V
10
100
1,000
SUPPLY CURRENT (µA) AT 2.7VDD
SUPPLY CURRENT (µA) AT 5.5VDD
35
30
25
20
15
TEST CONDITIONS:
CLEAR + RGB + IR MODE
AMBTIM = 000, AMBPGA = 00
LIGHT SOURCE: SUNLIGHT
VDD = 2.7V AND 5.5V
10
5
0
10,000 100,000
REFERENCE METER READING (lux)
Maxim Integrated
40
1
10
100
1,000
10,000 100,000
REFERENCE METER READING (lux)
80
70
60
50
40
30
20
10
0
-10
-20
-30
-40
MAX44006/08 toc10
SUPPLY CURRENT vs. LUX
(MAX44008)
TEMPERATURE SENSOR READINGS (°C)
SUPPLY CURRENT vs. LUX
(MAX44006)
15
1
0
10
TEMPERATURE (°C)
20
0
-20
15
TEMPERATURE (°C)
25
5
-40
TEST CONDITIONS:
AMBTIM[2:0] = 000
AMBPGA[1:0] = 00
POWER DENSITY (µW/cm2)
30
10
20
0
10,000
SUPPLY CURRENT (µA)
1
25
SUPPLY CURRENT (µA)
1,000
TEST CONDITIONS:
AMBTIM[2:0] = 000, ALL PGA SETTING = 0
20
SUPPLY CURRENT (µA)
MAX44006/08 toc07
10,000
25
MAX44006/08 toc08a
ILLUMINANCE (lux)
MAX44006/08 toc08
ILLUMINANCE (lux)
100,000
COUNTS READINGS
CLEAR CHANNEL RESPONSE vs. GREEN LED
GREEN CHANNEL RESPONSE vs. GREEN LED
RED CHANNEL RESPONSE vs. RED LED
75,000
50,000
CLEAR CHANNEL
IR CHANNEL
100,000
LINIARITY RESPONSE vs. RGB LED
250,000
MAX44006/08 toc05
175,000
200,000
SUPPLY CURRNET (µA)
TEST CONDITIONS:
WHEN THE COUNT READINGS IN ONE PGA
SETTING ARE SATURATED, CHANGE PGA SETTING
TO THE LOWER SENSITIVITY PGA GAIN SETTING.
EX: PGA [1:0] = 00 -> PGA [1:0] = 01
CENTER TRIMMED UNIT
200,000
MAX44006/08 toc09a
READINGS (COUNTS)
600,000
MAX44006/08 toc04
TEST CONDITIONS:
WHEN THE COUNT READINGS IN ONE PGA
SETTING ARE SATURATED, CHANGE PGA SETTING
TO THE LOWER SENSITIVITY PGA GAIN SETTING.
EX: PGA [1:0] = 00 -> PGA [1:0] = 01
CENTER TRIMMED UNIT
700,000
225,000
READINGS (COUNTS)
800,000
RESPONSE OF CLEAR AND IR CHANNELS
WITH FLUROSCENT LIGHT
COUNTS
RESPONSE OF CLEAR AND IR CHANNELS
WITH INCANDESCENT LIGHT
80y = 0.0001x2 + 0.9709x + 1.7085
x : TEMPERATURE
y: TEMPERATURE SENSOR READINGS
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80
TEMPERATURE (°C)
5
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Typical Operating Characteristics (continued)
(VCC = 1.8V (MAX44006), VCC = 3.3V (MAX44008), TA = +25NC, min/max are from -40°C to +85°C, unless otherwise noted.)
SINK CURRENT vs. VINT LOW
10
8
6
12,000
10,000
8,000
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
6,000
4,000
2
2,000
0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40
POWER DENSITY (µW/cm2)
LIGHT SOURCE:
630nm RED LED
0
50 100 150 200 250 300 350 400 450
12,000
10,000
8,000
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
MAX44066/08 toc15
LIGHT SOURCE:
530nm GREEN LED
16,000
14,000
COUNTS READINGS
COUNTS READINGS
6,000
BLUE CHANNEL LINIARITY RESPONSE
0
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
12,000
10,000
8,000
6,000
4,000
LIGHT SOURCE:
470nm GREEN LED
2,000
0
0
50 100 150 200 250 300 350 400 450
POWER DENSITY (µW/cm2)
Maxim Integrated
8,000
18,000
MAX44066/08 toc14
16,000
2,000
PGA [1:0] = 00
PGA [1:0] = 01
PGA [1:0] = 10
PGA [1:0] = 11
10,000
POWER DENSITY (µW/cm2)
GREEN CHANNEL LINIARITY RESPONSE
4,000
12,000
2,000
50 100 150 200 250 300 350 400 450
18,000
6,000
14,000
0
0
VINT (V)
14,000
16,000
4,000
0
0
MAX44066/08 toc13
14,000
4
0
LIGHT SOURCE:
530nm GREEN LED
COUNTS READINGS
16,000
COUNTS READINGS
SINK CURRENT (mA)
12
RED CHANNEL LINIARITY RESPONSE
18,000
MAX44066/08 toc12
TEST CONDITIONS:
AMBINT INTERRUPT CONDITION,VINT LOW
14
CLEAR CHANNEL LINIARITY RESPONSE
18,000
MAX44006/08 toc11
16
0
50 100 150 200 250 300 350 400 450
POWER DENSITY (µW/cm2)
6
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Pin Configuration
TOP VIEW
SDA
SCL
INT
6
5
4
MAX44006
MAX44008
1
2
3
VDD
GND
A0
Pin Description
PIN
NAME
1
VDD
Power Supply
FUNCTION
2
GND
Ground
3
A0
Address Select. Pull high to select address 1000 100x (MAX44006), 1000 000x (MAX44008) or low
to select address 1000 101x (MAX44006), 1000 001x (MAX44008).
4
INT
Interrupt
5
SCL
I2C Clock
6
SDA
I2C Data
Detailed Description
The data is then stored in an output register that can be
read by an I2C master.
The MAX44006/MAX44008 combine a wide-dynamic
range color sensor capable of measuring red, green,
and blue (RGB) and infrared content of ambient light.
The devices also have a digital I2C interface, advanced
TEMP sensor, and interrupt pin functionality to make
interfacing with it easy. The die is placed inside an optically transparent (OTDFN) package.
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 conversions for
multiple channels.
A photodiode array inside the devices converts the light
to a current, which is then processed by low-power circuitry and a sigma-delta ADC into a digital bit stream.
Maxim Integrated
Key features of the devices include high-level integration,
low-power design, small packaging, and interrupt pin
operation. An on-chip programmable interrupt function
eliminates the need to continually poll the devices for
data, resulting in a significant power saving.
7
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Ambient Light Sensing
WAVELENGTH vs. COUNTS
Ambient light sensors are designed to detect brightness
the same way 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. See Figure 1.
14,000
12,000
10,000
COUNTS
The devices’ 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 power-efficient sleep mode until a change in lighting
condition alerts it.
COMPENSATION DISABLED
POWER DENSITY 15.83µW/cm2
AMBPGA [1:0] = 00
AMBTIM[2:0] = 000
8,000
CLEAR
RED
GREEN
BLUE
IR
6,000
4,000
2,000
0
250 350 450 550 650 750 850 950 1050
WAVELENGTH (nm)
Variation between light sources can extend beyond
the visible spectral range—fluorescent, incandescent,
and sunlight, for example, have substantially different
IR radiation content. The devices incorporate 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.
Figure 1. Wavelength vs. Counts
be tailored for specific applications, such as when the
light sensor is placed under a colored or black glass.
Temperature Sensor
The devices also integrate 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.
On-chip user-programmable clear, RGB, infrared channel gain registers allow the light sensor response to also
Register Description
REGISTER
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
RESET
SHDN
PWRON
BIT1
BIT0
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
AMBINTS
0x00
0X04
R/W
AMBINTE
0x01
0x00
R/W
0x02
0x20
R/W
STATUS
Interrupt
Status
CONFIGURATION
Main
Configuration
Ambient
Configuration
Maxim Integrated
MODE[1:0]
TRIM
COMPEN TEMPEN
AMBSEL[1:0]
AMBTIM[2:0]
AMBPGA[1:0]
8
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Register Description (continued)
REGISTER
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
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
0x12
0x00
R
AMBIENT 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
Ambient
INFRARED
High Byte
Ambient
INFRARED
Low Byte
Ambient IR
COMP High
Byte
Ambient IR
COMP Low
Byte
TEMP High
Byte
Maxim Integrated
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]
AMB_IR[13:8]
AMB_IR[7:0]
AMB_IRCOMP[13:8]
AMB_IRCOMP[7:0]
TEMP[13:8]
9
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Register Description (continued)
REGISTER
BIT7
BIT6
TEMP Low
Byte
BIT5
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
0x13
0x00
R
0x14
0xFF
R/W
0x15
0xFF
R/W
0x16
0x00
R/W
0x17
0x00
R/W
0x18
0x00
R/W
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
BIT4
BIT3
BIT2
BIT1
BIT0
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
UPTHR[13:8]
UPTHR[7:0]
LOTHR[13:8]
LOTHR[7:0]
Threshold
Persist Timer
AMBPST[1:0]
AMBIENT ADC GAINS
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
Maxim Integrated
10
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
The individual register bits are explained below.
Interrupt Status (0x00)
REGISTER
BIT7
BIT6
Interrupt
Status
BIT5
BIT4
BIT3
BIT2
RESET
SHDN
PWRON
BIT1
BIT0
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
AMBINTS
0x00
0x04
R/W
The AMBINTS bit in the Interrupt Status register 0x00 is a read-only bit, and indicates that an ambient light-interrupt
condition has occurred. If any of these bits (PWRON, AMBINTS) are set to 1, the INT pin is pulled low. The PWRON bit
in the Interrupt Status register 0x00 is a read-only bit, and if set, indicates that a power-on-reset (POR) condition has
occurred, and any user-programmed thresholds may not be valid anymore. The SHDN bit in the Interrupt Status register
0x00 is a read/write bit, 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 Interrupt Status register 0x00 is also a read/write bit, and
can be used to reset all the registers back to a power-on default condition.
Reading the Interrupt Status register clears the PWRON and AMBINTS bits if set, and deasserts the INT pin (INT pin is
pulled high by the off-chip pullup resistor). The AMBINTS bits are disabled and set to 0 if the respective INTE 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 the 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. 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 power-supply
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.
Table 3. Shutdown Control (SHDN)
BIT3
OPERATION
0
The part is in normal operation. When the part returns from shutdown, note that the value in data registers is not current
until the 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 approximately
0.01FA (MAX44006) and 0.5FA (MAX44008) 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.
Maxim Integrated
11
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Table 4. Reset Control (RESET)
BIT4
OPERATION
0
The part is in normal operation.
1
The part undergoes a forced POR sequence. All configuration, threshold, and data registers are reset to a 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
BIT4
MODE[1:0]
BIT3
BIT2
BIT1
AMBSEL[1:0]
BIT0
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
AMBINTE
0x01
0x20
R/W
Writing to the Main Configuration register does not abort any ambient data conversion (registers 0x04 to 0x0F) if already
in progress. It applies the new settings during the next conversion period.
Table 5. 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 the AMBINTS bit for more details). An ambient interrupt can
trigger a hardware interrupt (INT pin pulled low) and set the AMBINTS bit (register 0x00, BIT0).
Note: Detection of an ambient interrupt event sets the AMBINTS bit (register 0x00, BIT0) only if AMBINTE bit is set to
1. If AMBINTS bits are set to 1, it pulls the interrupt INT pin low (asserts it). A read of the Interrupt Status register clears
AMBINTS bits if set to 1, and deasserts the INT pin if pulled low.
The 2 AMBSEL[1:0] bits define four operating modes for the devices. Ensure that the respective ambient channels also
enable use of the MODE[1:0] bits.
Table 6. 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.
Maxim Integrated
12
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
The 2 MODE[1:0] bits define three operating modes for the devices, as shown in Table 7.
Table 7. MODE[1:0]
MODE[1:0]
OPERATING MODE
COMMENTS
00
Clear
CLEAR + TEMP* channels active
01
Clear + IR
CLEAR + TEMP* + IR channels active
10
Clear + RGB + IR
CLEAR + TEMP* + RGB + IR channels active
*When TEMPEN set to 1.
Ambient Configuration Register (0x02)
REGISTER
BIT7
Ambient
Configuration
TRIM
BIT6
BIT5
COMPEN TEMPEN
BIT4
BIT3
AMBTIM[2:0]
BIT2
BIT1
BIT0
AMBPGA[1:0]
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
0x02
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
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
The 2 AMBPGA[1:0] bits set the gain of the clear/red/green/blue/IR channel measurements according to Table 8.
Table 8. 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
32
524.288
32
524.288
32
524.288
11
512
8388.61
512
8388.61
512
8388.61
AMBPGA[1:0]
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
00
4
65.536
2
32.768
01
16
262.144
8
131.072
10
64
1048.573
32
524.288
11
1024
16777.2
512
8388.61
BLUE
IR
In AMBTIM[2:0] = 100 Mode (400ms 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
0.5
8.192
0.5
8.192
0.5
8.192
01
2
32.768
2
32.768
2
32.768
10
8
131.072
8
131.072
8
131.072
11
128
2097.153
128
2097.153
128
2097.153
AMBPGA[1:0]
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
nW/cm2 per
LSB*
FULL SCALE
(µW/cm2)
1
16.384
0.5
8.192
BLUE
00
IR
01
4
65.536
2
32.768
10
16
262.1433
8
131.072
11
256
4194.3
128
2097.153
Maxim Integrated
14
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
The 3 AMBTIM[2:0] bits set the integration time for the red/green/blue/IR/temp channel ADC conversion, as shown in
Table 9.
Table 9. 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 10. TEMPEN
BIT6
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 11. COMPEN
BIT5
OPERATION
0
Disables IR compensation.
1
Enables IR compensation. Only for MODE[1:0] = 00 Mode.
The integration time of compensation channel is controlled by the AMB 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
leakeds and temperature variations. When COMPEN = 0, the IR compensation is disabled, but the output of the IR
compensation data exits.
Table 12. TRIM Adjust Enable (TRIM)
BIT7
OPERATION
0
Use factory-programmed gains for all the channels. Ignore any bytes written to 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 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
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
AMBIENT Data Register (0x04–0x0F)
REGISTER
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
BIT1
BIT0
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
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
AMBIENT 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
Ambient
INFRARED
High Byte
Ambient
INFRARED
Low Byte
Ambient IR
COMP High
Byte
Ambient IR
COMP 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]
AMB_IR[13:8]
AMB_IR[7:0]
AMB_IRCOMP[13:8]
AMB_IRCOMP[7:0]
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 devices. The resolution and bit length of the result is controlled by the value of the
AMBTIM[2:0] and AMBPGA[1:0] bits. The result is always right justified in the registers, and the unused high bits are
set to zero.
Maxim Integrated
16
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Temperature Data Register (0x12–0x13)
REGISTER
BIT7
BIT6
BIT5
BIT4
TEMP High
Byte
BIT3
BIT2
BIT1
BIT0
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
0x12
0X00
R
0x13
0X00
R
TEMP[13.8]
TEMP Low
Byte
TEMP[7.0]
Ambient Interrupt Threshold Registers (0x14–0x17)
REGISTER
AMB Upper
Threshold—
High Byte
AMB Upper
Threshold—
Low Byte
AMB Lower
Threshold—
High Byte
AMB Lower
Threshold—
Low Byte
BIT7
BIT6
BIT5
BIT4
BIT3
BIT2
UPTHR[13:8]
UPTHR[7:0]
LOTHR[13:8]
LOTHR[7:0]
BIT1
BIT0
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
0x14
0xFF
R/W
0x15
0xFF
R/W
0x16
0x00
R/W
0x17
0x00
R/W
The ambient upper threshold and lower threshold (UPTHR[13:0] and LOTHR[13:0]) 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 2
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 is
set and the INT pin is pulled low.
Maxim Integrated
17
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Ambient Threshold Persist Timer Register (0x18)
REGISTER
BIT7
BIT6
BIT5
Threshold
Persist Timer
BIT4
BIT3
BIT2
BIT1
BIT0
AMBPST[1:0]
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
0x18
0x00
R/W
AMBPST[1:0] sets one of four persist values in Table 13 that control a time delay before the interrupt logic reacts to a
detected event. This feature is added in order to reduce false or nuisance interrupts.
Table 13. AMBPST[1:0]
AMBPST[1:0]
00
01
10
11
NO. OF CONSECUTIVE MEASUREMENTS REQUIRED TO TRIGGER AN INTERRUPT
1
4
8
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.
Maxim Integrated
18
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Gain Trim Registers (0x1D–0x21)
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
REGISTER
ADDRESS
POWERON
RESET
STATE
R/W
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
BIT4
BIT3
BIT2
BIT1
BIT0
TRIM_GAIN_CLEAR is used to trim the gain of the clear channel. 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, and 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
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Applications Information
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 accurate
ambient-light readings can be generated 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
property of attenuating most ambient light but passing
through infrared radiation.
Ambient Sensing Applications
Typical applications involve placing the devices behind
a glass with a small semitransparent window above it.
Use the photodiode sensitive area as shown in Figure 2
to properly position the window above the part.
It is possible to map the RGB color values to an XY coordinate system for ambient color temperature measurement. This information can be used to enhance quality
of image display by allowing the instrument to compensate for the human eye’s chromatic adaptation—a form
of improved autowhite balance. It can also be used to
improve the color gamut of RGB LED backlit displays by
allowing precise white point adjustment of LED sources.
Interrupt Operation
Ambient interrupt is enabled by setting bit 0 of register
0x01 to 1. See Table 5. The interrupt pin, INT, is an
open-drain output and pulls low when an interrupt con-
2000µm
750µm
490µm
750µm
350µm
VDD
6
1
SDA
IR SENSOR
160µm
130µm
650µm
GND
A0
300µm
185µm
2
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
MAX44006/MAX44008
285µm
610µm
SCL
INT
240µm
Figure 2. Photodiode Location
Maxim Integrated
20
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
dition 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,
as can happen in instruments during vibration or power
fluctuations.
It is recommended to utilize the INT pin on the devices to
alert the master to read measurements from the devices.
This eliminates the need for the microcontroller (I2C master) to continually poll the devices 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 the
devices’ performance. The wide variety of smarts available on the chip, such as the 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
The typical operating sequence for the master to communicate to the devices is shown below:
1) Setup:
a) Read the Interrupt Status register (0x00) to confirm
only the PWRON bit is set (usually at power-up
only). This also clears the hardware interrupt.
b) Set Threshold and Persist Timer registers for ambient measurements.
c) Write 0x00 to Ambient Configuration register (register 0x02) to set the AMB sensor in the most
sensitive gain setting, and the AMB ADCs in 14-bit
modes of operation.
d) Write 0x21 to the Main Configuration register (register 0x01) to set the part in CLEAR + TEMP + RGB
+ IR mode and to enable AMB interrupt.
e) (Optional: Set new CLEAR, RGB, and infrared
channel gains if necessary and set TRIM bit in
register 0x02 to 1).
2) Wait for interrupt.
3) On interrupt:
a) Read the Interrupt Status register (0x00) to confirm
the IC to be the source of interrupt. This should
clear the hardware interrupt on the part, if set.
b) If an AMB interrupt has occurred, read AMB registers (register 0x04–0x0D) and take appropriate
action (e.g., sets new backlight strength/change
display gamma). Set new AMB thresholds, if necessary.
c) Return to Step 2.
I2C Serial Interface
The devices feature an I2C /SMBusK-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 devices 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 transfer on the bus. A master device
writes data to the devices 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 devices
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
Table 14. Slave Address
A0
SLAVE ADDRESS FOR WRITING
SLAVE ADDRESS FOR READING
GND
1000 1010
1000 1011
VDD
1000 1000
1000 1001
GND
1000 0010
1000 0011
VDD
1000 0000
1000 0001
MAX44006
MAX44008
Maxim Integrated
21
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
pulses. The devices transmit 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 (NACK), 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 devices
from high-voltage spikes on the bus lines and minimize
crosstalk and undershoot of the bus signal.
section. SDA and SCL idle high when the I2C bus is not
busy.
Bit Transfer
The devices recognize 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.
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
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.
Early STOP Conditions
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
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Acknowledge
The acknowledge bit (ACK) is a clocked 9th bit that the
devices use to handshake receipt of each byte of data
when in write mode (Figure 5). The devices pull 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
can retry communication. The master pulls down SDA
during the ninth clock cycle to acknowledge receipt of
data when the devices are in read mode. An acknowledge is sent by the master after each read byte to allow
data transfer to continue. A not acknowledge (NACK) is
sent when the master reads the final byte of data from the
device, followed by a STOP condition.
Write Data Format
A write to the devices includes transmission of a START
condition, the slave address with the R/W bit set to 0, 1
byte of data to configure the internal register address
pointer, 1 or more bytes of data, and a STOP condition.
Figure 6 illustrates the proper frame format for writing 1
byte of data to the devices. Figure 7 illustrates the frame
format for writing n-bytes of data to the devices.
The slave address with the R/W bit set to 0 indicates
that the master intends to write data to the devices. The
devices acknowledge receipt of the address byte during
the master-generated ninth SCL pulse.
The second byte transmitted from the master configures
the devices’ internal register address pointer. The pointer
tells the devices where to write the next byte of data. An
acknowledge pulse is sent by the devices upon receipt
of the address pointer data.
The third byte sent to the devices contains the data that is
written to the chosen register. An acknowledge pulse from
the devices 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.
ACKNOWLEDGE FROM MAX44006/MAX44008
B7
ACKNOWLEDGE FROM MAX44006/MAX44008
SLAVE ADDRESS
S
0
B6
B5
B4
B3
B2
B1
B0
ACKNOWLEDGE FROM MAX44006/MAX44008
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 MAX44006/MAX44008
ACKNOWLEDGE FROM
MAX44006/MAX44008
S
SLAVE ADDRESS
0
A
REGISTER ADDRESS
ACKNOWLEDGE FROM
MAX44006/MAX44008
ACKNOWLEDGE FROM
MAX44006/MAX44008
ACKNOWLEDGE FROM
MAX44006/MAX44008
B7 B6 B5 B4 B3 B2 B1 B0
B7 B6 B5 B4 B3 B2 B1 B0
A
R/W
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 MAX44006/MAX44008
Maxim Integrated
23
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Read Data Format
master presets the address pointer by first sending the
devices’ 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 devices transmit 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 NACK from the
master and then a STOP condition. Figure 8 illustrates
the frame format for reading 1 byte from the devices.
Figure 9 illustrates the frame format for reading multiple
bytes from the devices. Figure 10 illustrates the frame
format for reading two registers consecutively without a
STOP condition in between reads.
Send the slave address with the R/W bit set to 1 to initiate a read operation. The devices acknowledge receipt
of the 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 devices comprises
the contents 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 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
ACKNOWLEDGE FROM
MAX44006/MAX44008
ACKNOWLEDGE FROM
MAX44006/MAX44008
S
SLAVE ADDRESS
0
A
A
REGISTER ADDRESS
Sr
SLAVE ADDRESS
1
REPEATED START
R/W
NOT ACKNOWLEDGE FROM MASTER
ACKNOWLEDGE FROM
MAX44006/MAX44008
A
A
DATA BYTE
R/W
P
1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
Figure 8. Reading 1 Indexed Byte of Data from the MAX44006/MAX44008
ACKNOWLEDGE FROM
MAX44006/MAX44008
S
SLAVE ADDRESS
0
ACKNOWLEDGE FROM
MAX44006/MAX44008
A
A
REGISTER ADDRESS
R/W
ACKNOWLEDGE FROM
MAX44006/MAX44008
Sr
SLAVE ADDRESS
1
REPEATED START
A
A
DATA BYTE
R/W
P
1 BYTE
AUTOINCREMENT INTERNAL
REGISTER ADDRESS POINTER
Figure 9. Reading n-Bytes of Indexed Data from the MAX44006/MAX44008
S
SLAVE ADDRESS
REGISTER 1 DATA
0
A
A
REGISTER ADDRESS 1
REGISTER 2 DATA
A
A
Sr
SLAVE ADDRESS
1
A
P
Figure 10. Reading Two Registers Consecutively Without a STOP Condition in Between Reads
Maxim Integrated
24
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Typical Operating Circuit
1.7V TO 2V (MAX44006)
2.7V TO 5.5V (MAX44008)
1.4V TO 5.5V
1µF
10kI
10kI
10kI
VDD
SDA
SDA
GND
SCL
SCL
A0
INT
INT
SDA
MAX44006
MAX44008
SCL
SCL
I2C SLAVE_1
I2C SLAVE_n
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX44006EDT+
-40NC to +85NC
6 OTDFN
MAX44006EDT+T
-40NC to +85NC
6 OTDFN
MAX44008EDT+
-40NC to +85NC
6 OTDFN
MAX44008EDT+T
-40NC to +85NC
6 OTDFN
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
Maxim Integrated
MICROCONTROLLER
(I2C MASTER)
SDA
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
25
MAX44006/MAX44008
RGB Color, Infrared, and Temperature Sensors
Revision History
REVISION
NUMBER
REVISION
DATE
0
7/12
Initial release
1
8/12
Updated the General Description, Features, Pin Description, AMBIENT Data Register
(0x04–0x0F) sections, and Tables 3 and 14
DESCRIPTION
PAGES
CHANGED
—
1, 7, 11,
16, 21
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.
Maxim 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
26
The Maxim logo and Maxim Integrated are trademarks of Maxim Integrated Products, Inc.
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