19-6298; Rev 0; 7/12 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 from 1.8V/3.3V/5.5V supply voltage rails. 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. Features S Optical Sensor Fusion for True Color Sensing Six Parallel ADCs R, G, B, IR, ALS Sensing S Superior Sensitivity 0.001 Lux S Optimized for Overall System Power Consumption 10A (MAX44006)/10A (MAX44008) in Ambient Mode 15A (MAX44006)/16A (MAX44008) in RGBC + IR Mode 0.01A (MAX44006)/0.5A (MAX44008) in Shutdown Mode S Digital Functionalities Programmable Channel Gains Adjustable Interrupt Thresholds S High-Level Integration Seven Sensors in a 2mm x 2mm x 0.6mm Package Functional Diagram VDD MAX44006 MAX44008 RED AMB PGA 14-BIT ADC SDA GREEN 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 SCL Applications BLUE TVs/Display Systems Tablet PCs/Notebooks/e-Readers Printers MICROCONTROLLER I2C CLEAR INT LED and Laser Projectors Digital Light Management COMP Industrial Sensors Tablets IR Color Correction Ordering Information appears at end of data sheet. For related parts and recommended products to use with this part, refer to www.maxim-ic.com/MAX44006.related. TEMP GND 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.maxim-ic.com. 1 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).....+83.9C/W Junction-to-Case Thermal Resistance (BJC)............. +37C/W Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (VDD = 1.8V (MAX44006), VDD = 3.3V (MAX44008), TA = +25NC, min/max are from -40C to +85C, 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 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 -40C to +85C, 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 Output Low Voltage SDA VOL ISINK = 6mA 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 1.4 200 CIN IIN 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) Serial Clock Frequency fSCL 0 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 400 kHz tHIGH 0.6 Fs tSU.STA 0.6 Fs Setup Time for STOP Condition tSU,STO 0.6 Data Hold Time tHD,DAT 0 Data Setup Time tSU,DAT 100 Bus Capacitance CB Setup Time for a Repeated START Fs 0.9 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 -40C to +85C, 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 -40C to +85C, unless otherwise noted.) SPECTRUM OF LIGHT SOURCES FOR MEASUREMENT 8,000 6,000 4,000 120 100 60 40 20 0 0 WAVELENGTH (nm) 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 W/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 -40C to +85C, 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 (W/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 40 SUPPLY CURRENT (A) AT 2.7VDD SUPPLY CURRENT (A) 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) 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 (W/cm2) 30 10 20 0 10,000 SUPPLY CURRENT (A) 1 25 SUPPLY CURRENT (A) 1,000 TEST CONDITIONS: AMBTIM[2:0] = 000, ALL PGA SETTING = 0 20 SUPPLY CURRENT (A) 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 (A) 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 -40C to +85C, unless otherwise noted.) SINK CURRENT vs. VINT LOW 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 (W/cm2) 8,000 6,000 LIGHT SOURCE: 630nm RED LED 50 100 150 200 250 300 350 400 450 BLUE CHANNEL LINIARITY RESPONSE 12,000 10,000 8,000 PGA [1:0] = 00 PGA [1:0] = 01 PGA [1:0] = 10 PGA [1:0] = 11 0 MAX44066/08 toc15 16,000 14,000 COUNTS READINGS LIGHT SOURCE: 530nm GREEN LED 0 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 (W/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 10 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 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 (W/cm2) 0 50 100 150 200 250 300 350 400 450 POWER DENSITY (W/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 or low to select address 1000 101x. 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. 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 15.83W/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 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 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 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 0.05FA 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. 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. 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. 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* 00 01 RED FULL SCALE (W/cm2) nW/cm2 per LSB* 2 32.768 8 131.072 10 32 11 512 AMBPGA[1:0] nW/cm2 per GREEN FULL SCALE (W/cm2) nW/cm2 per LSB* 2 32.768 2 32.768 8 131.072 8 131.072 524.288 32 524.288 32 524.288 8388.61 512 8388.61 512 8388.61 LSB* FULL SCALE (W/cm2) nW/cm2 per LSB* FULL SCALE (W/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 FULL SCALE (W/cm2) IR In AMBTIM[2:0] = 100 Mode (400ms integration time) CLEAR AMBPGA[1:0] nW/cm2 per LSB* 00 01 RED FULL SCALE (W/cm2) nW/cm2 per LSB* 0.5 8.192 2 32.768 10 8 11 128 AMBPGA[1:0] nW/cm2 per nW/cm2 per LSB* 0.5 8.192 0.5 8.192 2 32.768 2 32.768 131.072 8 131.072 8 131.072 2097.153 128 2097.153 128 2097.153 LSB* FULL SCALE (W/cm2) nW/cm2 per LSB* FULL SCALE (W/cm2) 1 16.384 0.5 8.192 BLUE 00 GREEN FULL SCALE (W/cm2) FULL SCALE (W/cm2) IR 01 4 65.536 2 32.768 10 16 262.1433 8 131.072 11 256 4194.3 128 2097.153 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. 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] 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 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. 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. 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. 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. 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- 2000m 750m 490m 750m 350m VDD 6 1 SDA IR SENSOR 160m 130m 650m GND A0 300m 185m 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 2000m 4 MAX44006/MAX44008 285m 610m SCL INT 240m Figure 2. Photodiode Location 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 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 Table 14. Slave Address A0 SLAVE ADDRESS FOR WRITING SLAVE ADDRESS FOR READING GND 1000 1010 1000 1011 VDD 1000 1000 1000 1001 SMBus is a trademark of Intel Corp. 21 MAX44006/MAX44008 RGB Color, Infrared, and Temperature Sensors 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. 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. 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 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 Early STOP Conditions 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. 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 Figure 5. Acknowledge 22 MAX44006/MAX44008 RGB Color, Infrared, and Temperature Sensors 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 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 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 1F 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. MICROCONTROLLER (I2C MASTER) SDA Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.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 DESCRIPTION Initial release PAGES CHANGED -- 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 Products, Inc. 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 (c) 2012 Maxim Integrated Products 26 Maxim is a registered trademark of Maxim Integrated Products, Inc.