OPT3007YMFR

Order Now Product Folder Support & Community Tools & Software Technical Documents OPT3007 SBOS864 – AUGUST 2017 OPT3007 Ultra-Thin Ambient Light Sensor 1 Features 3 Description • The OPT3007 is a single-chip lux meter, measuring the intensity of visible light as seen by the human eye. The OPT3007 is available in an ultra-small PicoStar package, so the device fits into tiny spaces. The OPT3007 has a fixed addressing scheme which enables the device to operate with only four pins connected. This enables the PCB designer to create a bigger opening to the active sensor area. 1 • • • • • • • • • • • • Precision Optical Filtering to Match Human Eye: – Rejects > 99% (Typical) of IR Automatic Full-Scale Setting Feature Measurements: 0.01 Lux to 83k Lux 23-Bit Effective Dynamic Range With Automatic Gain Ranging 12 Binary-Weighted Full-Scale Range Settings: < 0.2% (Typical) Matching Between Ranges Low Operating Current: 1.8 µA (Typical) Operating Temperature Range: –40°C to +85°C Wide Power-Supply Range: 1.6 V to 3.6 V Fixed I2C Address 5.5-V Tolerant I/O Fixed I2C Address Small-Form Factor: – 0.856-mm × 0.946-mm × 0.226-mm PicoStar™ Package OPT3007 is Smaller Version of OPT3001 2 Applications • • • • • • • Smart Watches Wearable Electronics Health Fitness Bands Display Backlight Controls Lighting Control Systems Tablet and Notebook Computers Cameras The precision spectral response of the sensor tightly matches the photopic response of the human eye. With strong infrared (IR) rejection, the OPT3007 measures the intensity of light as seen by the human eye, regardless of the light source. The IR rejection also aids in maintaining high accuracy when design requires mounting the sensor under dark glass. The OPT3007, often in conjunction with backlight ICs or lighting control systems, creates light-based experiences for humans, and is a replacement for photodiodes, photoresistors, or lower-performing ambient light sensors. Measurements can be made from 0.01 lux up to 83k lux without manually selecting full-scale ranges by using the built-in, full-scale setting feature. This capability allows light measurement over a 23-bit effective dynamic range. The digital operation is flexible for system integration. Measurements can be either continuous or singleshot. The digital output is reported over an I2C- and SMBus-compatible, two-wire serial interface. Device Information(1) PART NUMBER Spectral Response: The OPT3007 and Human Eye PicoStar (6) OPT3007 Human Eye Block Diagram 0.8 Normalized Response BODY SIZE (NOM) 0.856 mm × 0.946 mm × 0.226 mm (1) For all available packages, see the package option addendum at the end of the data sheet. 1 0.9 OPT3007 PACKAGE 0.7 VDD 0.6 0.5 VDD OPT3007 0.4 Ambient Light 0.3 0.2 Optical Filter ADC SCL I2C Interface SDA 0.1 0 300 GND 400 500 600 700 Wavelength (nm) 800 900 1000 Copyright © 2017, Texas Instruments Incorporated D001 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. OPT3007 SBOS864 – AUGUST 2017 www.ti.com Table of Contents 1 2 3 4 5 6 7 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Pin Configuration and Functions ......................... Specifications......................................................... 1 1 1 2 3 4 6.1 6.2 6.3 6.4 6.5 6.6 6.7 4 4 4 4 5 6 7 Absolute Maximum Ratings ...................................... ESD Ratings.............................................................. Recommended Operating Conditions....................... Thermal Information .................................................. Electrical Characteristics........................................... Timing Requirements ................................................ Typical Characteristics .............................................. 7.6 Register Maps ......................................................... 15 8 8.1 Application Information............................................ 23 8.2 Typical Application .................................................. 24 8.3 Do's and Don'ts ...................................................... 27 9 Power-Supply Recommendations...................... 27 10 Layout................................................................... 28 10.1 Layout Guidelines ................................................. 28 10.2 Soldering and Handling Recommendations.......... 28 10.3 Layout Example .................................................... 30 11 Device and Documentation Support ................. 31 11.1 11.2 11.3 11.4 11.5 11.6 Detailed Description ............................................ 10 7.1 7.2 7.3 7.4 7.5 Overview ................................................................. Functional Block Diagram ...................................... Feature Description................................................. Device Functional Modes........................................ Programming........................................................... Application and Implementation ........................ 23 10 10 11 12 12 Documentation Support ........................................ Receiving Notification of Documentation Updates Community Resources.......................................... Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 31 31 31 31 31 31 12 Mechanical, Packaging, and Orderable Information ........................................................... 31 4 Revision History 2 DATE REVISION NOTES August 2017 * Initial release. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 5 Pin Configuration and Functions YMF Package 6-Pin PicoStar Top View 1 2 A GND SCL B NC C VDD Optical Sensing Area NC SDA Pin Functions PIN NO. NAME TYPE A1 GND Power (1) B1 NC C1 VDD Power A2 SCL Digital input B2 C2 (1) NC (1) SDA — — Digital input/output DESCRIPTION Ground No connection required Device power. Connect to a 1.6-V to 3.6-V supply. I2C clock. Connect with a 10-kΩ resistor to a 1.6-V to 5.5-V supply. No connection required I2C data. Connect with a 10-kΩ resistor to a 1.6-V to 5.5-V supply. OPT3007 device has a fixed addressing scheme (see Serial Bus Address). This enables pin B1 and B2 to remain unconnected which enables creating a bigger opening for the sensor active area can be made wider for optimal device performance. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 3 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 6 Specifications 6.1 Absolute Maximum Ratings (1) Voltage MIN MAX UNIT VDD to GND –0.5 6 V SDA and SCL to GND –0.5 6 V 10 mA 150 °C 150 (2) °C Current into any pin Junction Temperature (1) (2) Storage, Tstg –65 Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. Long exposure to temperatures higher than 105°C can cause package discoloration, spectral distortion, and measurement inaccuracy. 6.2 ESD Ratings VALUE Electrostatic discharge V(ESD) (1) (2) Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1) ±2000 Charged-device model (CDM), per JEDEC specification JESD22-C101 (2) ±500 UNIT V JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process. 6.3 Recommended Operating Conditions MIN NOM MAX UNIT Operating temperature –40 85 °C Operating power-supply voltage 1.6 3.6 V 6.4 Thermal Information OPT3007 THERMAL METRIC (1) YMF (PicoStar) UNIT 6 PINS RθJA Junction-to-ambient thermal resistance 122.8 °C/W RθJC(top) Junction-to-case (top) thermal resistance 1.4 °C/W RθJB Junction-to-board thermal resistance 34.9 °C/W ψJT Junction-to-top characterization parameter 0.8 °C/W ψJB Junction-to-board characterization parameter 35.3 °C/W (1) 4 For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 6.5 Electrical Characteristics At TA = 25°C, VDD = 3.3 V, 800-ms conversion time (CT = 1) (1), automatic full-scale range (RN[3:0] = 1100b (1)), white LED, and normal-angle incidence of light, unless otherwise specified. PARAMETER TEST CONDITIONS MIN TYP MAX UNIT OPTICAL Peak irradiance spectral responsivity Lowest full-scale range, RN[3:0] = 0000b (1) Resolution (LSB) Full-scale illuminance 0.64 lux per ADC code, 2620.80 lux full-scale (RN[3:0] = 0110) (1), 2000 lux input (2) lux 3125 3750 ADC codes 1600 2000 2400 lux 0.2% (2) Light source variation (incandescent, halogen, fluorescent) Linearity Measurement drift across temperature lux 2500 Relative accuracy between gain ranges (3) PSRR nm 83865.6 Measurement output result Infrared response (850 nm) 550 0.01 0.2% Bare device, no cover glass 4% Input illuminance > 40 lux 2% Input illuminance < 40 lux 5% Input illuminance = 2000 lux 0.01 %/°C 0 3 0 0.03 ADC codes Dark condition, ADC output 0.01 lux per ADC code Half-power angle 50% of full-power reading 44 degrees Power-supply rejection ratio VDD at 3.6 V and 1.6 V 0.1 %/V (4) lux POWER SUPPLY VDD Operating range VI²C Operating range of I2C pull-up resistor I2C pullup resistor, VDD ≤ VI²C Dark IQ Quiescent current Full-scale lux POR Power-on-reset threshold 1.6 3.6 1.6 5.5 V V Active, VDD = 3.6 V 1.8 2.5 µA Shutdown (M[1:0] = 00) (1), VDD = 3.6 V 0.3 0.47 µA Active, VDD = 3.6 V 3.7 µA Shutdown, (M[1:0] = 00) (1) 0.4 µA 0.8 V TA = 25°C DIGITAL I/O pin capacitance Total integration time (5) 3 pF (CT = 1) (1), 800-ms mode, fixed lux range 720 800 880 ms (CT = 0) (1), 100-ms mode, fixed lux range 90 100 110 ms VIL Low-level input voltage (SDA and SCL) 0 0.3 × VDD V VIH High-level input voltage (SDA and SCL) 0.7 × VDD 5.5 V IIL Low-level input current (SDA and SCL) 0.25 (6) µA VOL Low-level output voltage (SDA) IOL= 3 mA 0.32 V IZH Output logic high, high-Z leakage current (SDA) Pin at VDD 0.25 (6) µA 85 °C 0.01 0.01 TEMPERATURE Specified temperature range (1) (2) (3) (4) (5) (6) –40 Refers to a control field within the configuration register. Tested with the white LED calibrated to 2k lux and an 850-nm LED. Characterized by measuring fixed near-full-scale light levels on the higher adjacent full-scale range setting. PSRR is the percent change of the measured lux output from its current value, divided by the change in power supply voltage, as characterized by results from 3.6-V and 1.6-V power supplies. The conversion time, from start of conversion until the data are ready to be read, is the integration time plus 3 ms. The specified leakage current is dominated by the production test equipment limitations. Typical values are much smaller. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 5 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 6.6 Timing Requirements (1) MIN TYP MAX UNIT 0.4 MHz I2C FAST MODE fSCL SCL operating frequency 0.01 tBUF Bus free time between stop and start 1300 ns tHDSTA Hold time after repeated start 600 ns tSUSTA Setup time for repeated start 600 ns tSUSTO Setup time for stop 600 ns tHDDAT Data hold time 20 tSUDAT Data setup time 100 ns tLOW SCL clock low period 1300 ns tHIGH SCL clock high period 600 tRC and tFC Clock rise and fall time 300 ns tRD and tFD Data rise and fall time 300 ns tTIMEO Bus timeout period. If the SCL line is held low for this duration of time, the bus state machine is reset. 900 ns ns 28 ms 2 I C HIGH-SPEED MODE fSCL SCL operating frequency 0.01 tBUF Bus free time between stop and start 160 ns tHDSTA Hold time after repeated start 160 ns tSUSTA Setup time for repeated start 160 ns tSUSTO Setup time for stop 160 tHDDAT Data hold time 20 tSUDAT Data setup time 20 ns tLOW SCL clock low period 240 ns tHIGH SCL clock high period 60 tRC and tFC Clock rise and fall time 40 ns tRD and tFD Data rise and fall time 80 ns tTIMEO Bus timeout period. If the SCL line is held low for this duration of time, the bus state machine is reset. (1) 2.6 MHz ns 140 ns ns 28 ms All timing parameters are referenced to low and high voltage thresholds of 30% and 70%, respectively, of final settled value. 1/fSCL tRC tFC 70% 30% SCL tLOW tHDDAT tHIGH tSUDAT tSUSTA tHDSTA tSUSTO 70% 30% SDA tBUF Stop Start tRD tFD Start Stop Figure 1. I2C Detailed Timing Diagram 6 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 6.7 Typical Characteristics At TA = 25°C, VDD = 3.3 V, 800-ms conversion time (CT = 1), automatic full-scale range (RN[3:0] = 1100b), white LED, and normal-angle incidence of light, unless otherwise specified. 300 1 OPT3007 Human Eye 0.9 Measurement (Lux) 0.8 Normalized Response Fluorescent Halogen Incandescent 250 0.7 0.6 0.5 0.4 0.3 0.2 200 150 100 50 0.1 0 0 300 400 500 600 700 Wavelength (nm) 800 900 0 1000 50 100 150 200 Input Light (Lux) 250 300 D002 D001 Figure 3. Output Response vs Input Illuminance, Multiple Light Sources (Fluorescent, Halogen, Incandescent) Figure 2. Spectral Response vs Wavelength 100 16000 Device Measurement (Lux) Device Measurement (Lux) 14000 12000 10000 8000 6000 4000 80 60 40 20 2000 0 0 0 2000 4000 0 6000 8000 10000 12000 14000 16000 Input Light (Lux) D003 Figure 4. Output Response vs Input Illuminance (Higher Range = 0 Lux to 16k Lux) 40 60 Input Light (Lux) 80 100 D004 Figure 5. Output Response vs Input Illuminance (Mid Range = 0 Lux to 100 Lux) 5 1.020 4 1.010 Relative Response Device Measurement (Lux) 20 3 2 1.005 1.000 1.000 1.001 1.003 1.000 1.000 0.990 1 0 0 1 2 3 Input Light (Lux) 4 5 0.980 40.95 D005 81.9 163.8 327.6 655.2 1310.4 Full-Scale Range (Lux) D006 Input illuminance = 30 lux, normalized to response of 40.95 lux full-scale Figure 6. Output Response vs Input Illuminance (Low Range = 0 Lux to 5 Lux) Figure 7. Full-Scale-Range Matching (Lowest 7 Ranges) Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 7 OPT3007 SBOS864 – AUGUST 2017 www.ti.com Typical Characteristics (continued) At TA = 25°C, VDD = 3.3 V, 800-ms conversion time (CT = 1), automatic full-scale range (RN[3:0] = 1100b), white LED, and normal-angle incidence of light, unless otherwise specified. 0.1 1.020 Dark Output Response (Lux) 0.09 Relative Response 1.010 1.000 1.000 1.000 1.000 0.999 0.998 0.997 0.997 0.990 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 -40 0.980 1310.4 2620.8 5241.6 10483.2 20966.4 41932.8 83865.6 Full-Scale Range (Lux) -20 0 D007 20 40 Temperature (qC) 60 80 100 D0016 Average of 30 devices Input illuminance = 960 lux, normalized to response of 2560 lux full-scale Figure 9. Dark Response vs Temperature Figure 8. Full-Scale-Range Matching (Highest 6 Ranges) 1.02 1000 Conversion Time (ms) Normalized Response 1.01 1 0.99 900 800 700 0.98 0.97 -40 -20 0 20 40 60 Temperature ( qC) 80 100 600 1.6 120 2 D008 Figure 10. Normalized Response vs Temperature 2.4 2.8 Power Supply (V) 3.2 3.6 D017 Figure 11. Conversion Time vs Power Supply 1 1.002 0.9 Normalized Response Normalized Response 0.8 1.001 1 0.999 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.998 1.6 2 2.4 2.8 Power Supply (V) 3.2 3.6 D009 Figure 12. Normalized Response vs Power-Supply Voltage 8 0 -90 -75 -60 -45 -30 -15 0 15 30 45 Incidence Angle (Degrees) 60 75 90 D010 Figure 13. Normalized Response vs Illuminance Angle Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 Typical Characteristics (continued) 4 0.5 3.5 0.45 Supply Current (PA) Supply Current (PA) At TA = 25°C, VDD = 3.3 V, 800-ms conversion time (CT = 1), automatic full-scale range (RN[3:0] = 1100b), white LED, and normal-angle incidence of light, unless otherwise specified. 3 2.5 2 0.4 0.35 0.3 0.25 1.5 0.2 1 100 1000 10000 Input Illuminance (Lux) 0 100000 20000 D011 M[1:0] = 10b Figure 14. Supply Current vs Input Illuminance D011 D012 Figure 15. Shutdown Current vs Input Illuminance 1.6 Shutdown Supply Current (PA) Vdd = 3.3V Vdd = 1.6V 3 Supply Current (PA) 80000 M[1:0] = 00b 3.5 2.5 2 1.5 1 -40 40000 60000 Input Illuminance (Lux) -20 0 20 40 Temperature (qC) 60 80 100 Vdd = 3.3V Vdd = 1.6V 1.4 1.2 1 0.8 0.6 0.4 0.2 -40 -20 D013 M[1:0] = 10b 0 20 40 Temperature (qC) 60 80 100 D014 M[1:0] = 00b, input illuminance = 0 lux Figure 16. Supply Current vs Temperature Figure 17. Shutdown Current vs Temperature 100 Shutdown Current (PA) Vdd = 3.3V Vdd = 1.6V 10 1 0.1 0.01 0.1 1 10 100 1000 Continuous I2C Frequency (KHz) 10000 D015 Input illuminance = 80 lux, SCL = SDA, continuously toggled at I2C frequency Note: A typical application runs at a lower duty cycle and thus consumes a lower current. Figure 18. Supply Current vs Continuous I2C Frequency Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 9 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 7 Detailed Description 7.1 Overview The OPT3007 measures the ambient light that illuminates the device. This device measures light with a spectral response very closely matched to the human eye, and with very good infrared rejection. Matching the sensor spectral response to that of the human eye response is vital because ambient light sensors are used to measure and help create ideal human lighting experiences. Strong rejection of infrared light, which a human does not see, is a crucial component of this matching. This matching makes the OPT3007 especially good for operation underneath windows that are visibly dark, but infrared transmissive. The OPT3007 is fully self-contained to measure the ambient light and report the result in lux digitally over the I2C bus. The OPT3007 can be configured into an automatic full-scale, range-setting mode that always selects the optimal full-scale range setting for the lighting conditions. This mode frees the user from having to program their software for potential iterative cycles of measurement and readjustment of the full-scale range until optimal for any given measurement. The device can be commanded to operate continuously or in single-shot measurement modes. The device integrates its result over either 100 ms or 800 ms, so the effects of 50-Hz and 60-Hz noise sources from typical light bulbs are nominally reduced to a minimum. The device starts up in a low-power shutdown state, such that the OPT3007 only consumes active-operation power after being programmed into an active state. The OPT3007 optical filtering system is not excessively sensitive to non-ideal particles and micro-shadows on the optical surface. This reduced sensitivity is a result of the relatively minor device dependency on uniformdensity optical illumination of the sensor area for infrared rejection. Proper optical surface cleanliness is always recommended for best results on all optical devices. 7.2 Functional Block Diagram VDD VDD OPT3007 Ambient Light Optical Filter ADC SCL I2C Interface SDA GND Copyright © 2017, Texas Instruments Incorporated 10 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 7.3 Feature Description 7.3.1 Human Eye Matching The OPT3007 spectral response closely matches that of the human eye. If the ambient light sensor measurement is used to help create a good human experience, or create optical conditions that are optimal for a human, the sensor must measure the same spectrum of light that a human sees. The device also has excellent infrared light (IR) rejection. This IR rejection is especially important because many real-world lighting sources have significant infrared content that humans do not see. If the sensor measures infrared light that the human eye does not see, then a true human experience is not accurately represented. Furthermore, if the ambient light sensor is hidden underneath a dark window (such that the end-product user cannot see the sensor) the infrared rejection of the OPT3007 becomes significantly more important because many dark windows attenuate visible light but transmit infrared light. This attenuation of visible light and lack of attenuation of IR light amplifies the ratio of the infrared light to visible light that illuminates the sensor. Results can still be well matched to the human eye under this condition because of the high infrared rejection of the OPT3007. 7.3.2 Automatic Full-Scale Range Setting The OPT3007 has an automatic full-scale range setting feature that eliminates the need to predict and set the optimal range for the device. In this mode, the OPT3007 automatically selects the optimal full-scale range for the given lighting condition. The OPT3007 has a high degree of result matching between the full-scale range settings. This matching eliminates the problem of varying results or the need for range-specific, user-calibrated gain factors when different full-scale ranges are chosen. For further details, see the Automatic Full-Scale Setting Mode section. 7.3.3 I2C Bus Overview The OPT3007 offers compatibility with both I2C and SMBus interfaces. The I2C and SMBus protocols are essentially compatible with one another. The I2C interface is used throughout this document as the primary example with the SMBus protocol specified only when a difference between the two protocols is discussed. The OPT3007 is connected to the bus with two pins: an SCL clock input pin and an SDA open-drain bidirectional data pin. The bus must be controlled by a master device that generates the serial clock (SCL), controls the bus access, and generates start and stop conditions. To address a specific device, the master initiates a start condition by pulling the data signal line (SDA) from a high logic level to a low logic level while SCL is high. All slaves on the bus shift in the slave address byte on the SCL rising edge, with the last bit indicating whether a read or write operation is intended. During the ninth clock pulse, the slave being addressed responds to the master by generating an acknowledge bit by pulling SDA low. Data transfer is then initiated and eight bits of data are sent, followed by an acknowledge bit. During data transfer, SDA must remain stable while SCL is high. Any change in SDA while SCL is high is interpreted as a start or stop condition. When all data are transferred, the master generates a stop condition, indicated by pulling SDA from low to high while SCL is high. The OPT3007 includes a 28-ms timeout on the I2C interface to prevent locking up the bus. If the SCL line is held low for this duration of time, the bus state machine is reset. 7.3.3.1 Serial Bus Address To communicate with the OPT3007, the master must first initiate an I2C start command. Then, the master must address slave devices via a slave address byte. The slave address byte consists of a seven bit address 1000101 and a direction bit that indicates whether the action is to be a read or write operation. 7.3.3.2 Serial Interface The OPT3007 operates as a slave device on both the I2C bus and SMBus. Connections to the bus are made via the SCL clock input line and the SDA open-drain I/O line. The OPT3007 supports the transmission protocol for standard mode (up to 100 kHz), fast mode (up to 400 kHz), and high-speed mode (up to 2.6 MHz). All data bytes are transmitted most-significant bits first. The SDA and SCL pins feature integrated spike-suppression filters and Schmitt triggers to minimize the effects of input spikes and bus noise. See the Electrical Interface section for further details of the I2C bus noise immunity. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 11 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 7.4 Device Functional Modes 7.4.1 Automatic Full-Scale Setting Mode The OPT3007 has an automatic full-scale-range setting mode that eliminates the need for a user to predict and set the optimal range for the device. This mode is entered when the configuration register range number field (RN[3:0]) is set to 1100b. The first measurement that the device takes in auto-range mode is a 10-ms range assessment measurement. The device then determines the appropriate full-scale range to take its first full measurement. For subsequent measurements, the full-scale range is set by the result of the previous measurement. If a measurement is towards the low side of full-scale, the full-scale range is decreased by one or two settings for the next measurement. If a measurement is towards the upper side of full-scale, the full-scale range is increased by one setting for the next measurement. If the measurement exceeds the full-scale range, resulting from a fast increasing optical transient event, the current measurement is aborted. This invalid measurement is not reported. If the scale is not at its maximum, the device increases the scale by one step and a new measurement is retaken with that scale. Therefore, during a fast increasing optical transient in this mode, a measurement can possibly take longer to complete and report than indicated by the configuration register conversion time field (CT). 7.5 Programming The OPT3007 supports the transmission protocol for standard mode (up to 100 kHz), fast mode (up to 400 kHz), and high-speed mode (up to 2.6 MHz). Fast and standard modes are described as the default protocol, referred to as F/S. High-speed mode is described in the High-Speed I2C Mode section. 7.5.1 Writing and Reading Accessing a specific register on the OPT3007 is accomplished by writing the appropriate register address during the I2C transaction sequence. Refer to Table 1 for a complete list of registers and their corresponding register addresses. The value for the register address (as shown in Figure 19) is the first byte transferred after the slave address byte with the R/W bit low. 1 9 1 9 SCL SDA 1 0 0 0 1 Start by Master 0 1 R/W RA 7 RA 6 RA 5 RA 4 RA 3 RA 2 RA 1 RA 0 ACK by Device Frame 1: Two-Wire Slave Address Byte (1) ACK by Device Stop by Master (optional) Frame 2: Register Address Byte Figure 19. Setting the I2C Register Address Writing to a register begins with the first byte transmitted by the master. This byte is the slave address with the R/W bit low. The OPT3007 then acknowledges receipt of a valid address. The next byte transmitted by the master is the address of the register that data are to be written to. The next two bytes are written to the register addressed by the register address. The OPT3007 acknowledges receipt of each data byte. The master may terminate the data transfer by generating a start or stop condition. When reading from the OPT3007, the last value stored in the register address by a write operation determines which register is read during a read operation. To change the register address for a read operation, a new partial I2C write transaction must be initiated. This partial write is accomplished by issuing a slave address byte with the R/W bit low, followed by the register address byte and a stop command. The master then generates a start condition and sends the slave address byte with the R/W bit high to initiate the read command. The next byte is 12 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 Programming (continued) transmitted by the slave and is the most significant byte of the register indicated by the register address. This byte is followed by an acknowledge from the master; then the slave transmits the least significant byte. The master acknowledges receipt of the data byte. The master may terminate the data transfer by generating a notacknowledge after receiving any data byte, or by generating a start or stop condition. If repeated reads from the same register are desired, continually sending the register address bytes is not necessary; the OPT3007 retains the register address until that number is changed by the next write operation. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 13 OPT3007 SBOS864 – AUGUST 2017 www.ti.com Programming (continued) Figure 20 and Figure 21 show the write and read operation timing diagrams, respectively. Note that register bytes are sent most significant byte first, followed by the least significant byte. 1 9 9 1 1 9 1 9 SCL SDA 1 0 0 0 1 0 1 Start by Master R/W RA 7 RA 6 RA 5 RA 4 RA 3 RA 2 RA 1 RA 0 ACK by Device Frame 1 Two-Wire Slave Address Byte (1) D15 D14 D13 D12 D11 D10 D9 Frame 2 Register Address Byte D8 D7 D6 D5 D4 D3 D2 D1 D0 ACK by Device ACK by Device ACK by Device Frame 3 Data MSByte Stop by Master Frame 4 Data LSByte Figure 20. I2C Write Example 1 9 1 9 1 9 SCL SDA 1 0 0 0 1 0 1 Start by Master D15 D14 D13 D12 D11 D10 D9 R/W ACK by Device Frame 1 Two-Wire Slave Address Byte (1) (1) From Device D8 D7 ACK by Master Frame 2 Data MSByte D6 D5 D4 D3 D2 D1 From Device D0 No ACK Stop by by Master Master(2) Frame 3 Data LSByte An ACK by the master can also be sent. Figure 21. I2C Read Example 7.5.1.1 High-Speed I2C Mode When the bus is idle, both the SDA and SCL lines are pulled high by the pullup resistors or active pullup devices. The master generates a start condition followed by a valid serial byte containing the high-speed (HS) master code 0000 1XXXb. This transmission is made in either standard mode or fast mode (up to 400 kHz). The OPT3007 does not acknowledge the HS master code but does recognize the code and switches its internal filters to support a 2.6-MHz operation. The master then generates a repeated start condition (a repeated start condition has the same timing as the start condition). After this repeated start condition, the protocol is the same as F/S mode, except that transmission speeds up to 2.6 MHz are allowed. Instead of using a stop condition, use repeated start conditions to secure the bus in HS mode. A stop condition ends the HS mode and switches all internal filters of the OPT3007 to support the F/S mode. 7.5.1.2 General-Call Reset Command The I2C general-call reset allows the host controller in one command to reset all devices on the bus that respond to the general-call reset command. The general call is initiated by writing to the I2C address 0 (0000 0000b). The reset command is initiated when the subsequent second address byte is 06h (0000 0110b). With this transaction, the device issues an acknowledge bit and sets all of its registers to the power-on-reset default condition. 14 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 7.6 Register Maps 7.6.1 Internal Registers The device is operated over the I2C bus with registers that contain configuration, status, and result information. All registers are 16 bits long. There are four main registers: result, configuration, low-limit, and high-limit. There are also two ID registers: manufacturer ID and device ID. Table 1 lists these registers. Table 1. Register Map REGISTER ADDRESS (HEX) (1) BIT 15 BIT 14 BIT 13 BIT 12 BIT 11 BIT 10 BIT 9 BIT 8 BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 Result 00h E3 E2 E1 E0 R11 R10 R9 R8 R7 R6 R5 R4 R3 R2 R1 R0 Configuration 01h RN3 RN2 RN1 RN0 CT M1 M0 OVF CRF FH FL L POL ME FC1 FC0 Low Limit 02h LE3 LE2 LE1 LE0 TL11 TL10 TL9 TL8 TL7 TL6 TL5 TL4 TL3 TL2 TL1 TL0 High Limit 03h HE3 HE2 HE1 HE0 TH11 TH10 TH9 TH8 TH7 TH6 TH5 TH4 TH3 TH2 TH1 TH0 Manufacturer ID 7Eh ID15 ID14 ID13 ID12 ID11 ID10 ID9 ID8 ID7 ID6 ID5 ID4 ID3 ID2 ID1 ID0 Device ID 7Fh DID15 DID14 DID13 DID12 DID11 DID10 DID9 DID8 DID7 DID6 DID5 DID4 DID3 DID2 DID1 DID0 (1) Register offset and register address are used interchangeably. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 15 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 7.6.1.1 Register Descriptions NOTE Register offset and register address are used interchangeably. 7.6.1.1.1 Result Register (Offset = 00h) This register contains the result of the most recent light to digital conversion. This 16-bit register has two fields: a 4-bit exponent and a 12-bit mantissa. Figure 22. Result Register (Read-Only) 15 E3 R 14 E2 R 13 E1 R 12 E0 R 11 R11 R 10 R10 R 9 R9 R 8 R8 R 7 R7 R 6 R6 R 5 R5 R 4 R4 R 3 R3 R 2 R2 R 1 R1 R 0 R0 R LEGEND: R = Read only Table 2. Result Register Field Descriptions Bit Field Type Reset Description 15:12 E[3:0] R 0h Exponent. These bits are the exponent bits. Table 3 provides further details. 11:0 R[11:0] R 000h Fractional result. These bits are the result in straight binary coding (zero to full-scale). Table 3. Full-Scale Range and LSB Size as a Function of Exponent Level E3 E2 E1 E0 FULL-SCALE RANGE (lux) LSB SIZE (lux per LSB) 0 0 0 0 40.95 0.01 0 0 0 1 81.90 0.02 0 0 1 0 163.80 0.04 0 0 1 1 327.60 0.08 0 1 0 0 655.20 0.16 0 1 0 1 1310.40 0.32 0 1 1 0 2620.80 0.64 0 1 1 1 5241.60 1.28 1 0 0 0 10483.20 2.56 1 0 0 1 20966.40 5.12 1 0 1 0 41932.80 10.24 1 0 1 1 83865.60 20.48 The formula to translate this register into lux is given in Equation 1: lux = LSB_Size × R[11:0] where • LSB_Size = 0.01 × 2E[3:0] (1) LSB_Size can also be taken from Table 3. The complete lux equation is shown in Equation 2: lux = 0.01 × (2E[3:0]) × R[11:0] (2) A series of result register output examples with the corresponding LSB weight and resulting lux are given in Table 4. Note that many combinations of exponents (E[3:0]) and fractional results (R[11:0]) can map onto the same lux result, as shown in the examples of Table 4. 16 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 Table 4. Examples of Decoding the Result Register into lux FRACTIONAL RESULT (R[11:0], HEX) LSB WEIGHT (LUX, DECIMAL) 00h 001h 0.01 0.01 00h FFFh 0.01 40.95 0011 0100 0101 0110b 03h 456h 0.08 88.80 0111 1000 1001 1010b 07h 89Ah 1.28 2818.56 1000 1000 0000 0000b 08h 800h 2.56 5242.88 1001 0100 0000 0000b 09h 400h 5.12 5242.88 1010 0010 0000 0000b 0Ah 200h 10.24 5242.88 1011 0001 0000 0000b 0Bh 100h 20.48 5242.88 1011 0000 0000 0001b 0Bh 001h 20.48 20.48 1011 1111 1111 1111b 0Bh FFFh 20.48 83865.60 RESULT REGISTER (BITS 15:0, BINARY) EXPONENT (E[3:0], HEX) 0000 0000 0000 0001b 0000 1111 1111 1111b RESULTING LUX (DECIMAL) Note that the exponent field can be disabled (set to zero) by enabling the exponent mask (configuration register, ME field = 1) and manually programming the full-scale range (configuration register, RN[3:0] < 1100b (0Ch)), allowing for simpler operation in a manually-programmed, full-scale mode. Calculating lux from the result register contents only requires multiplying the result register by the LSB weight (in lux) associated with the specific programmed full-scale range (see Table 3). See the Low-Limit Register for details. See the configuration register conversion time field (CT, bit 11) description for more information on lux resolution as a function of conversion time. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 17 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 7.6.1.1.2 Configuration Register (Offset = 01h) [Reset = C810h] This register controls the major operational modes of the device. This register has 11 fields, which are documented below. If a measurement conversion is in progress when the configuration register is written, the active measurement conversion immediately aborts. If the new configuration register directs a new conversion, that conversion is subsequently started. Figure 23. Configuration Register 15 RN3 R/W 14 RN2 R/W 13 RN1 R/W 12 RN0 R/W 11 CT R/W 10 M1 R/W 9 M0 R/W 8 OVF R 7 CRF R 6 FH R 5 FL R 4 L R/W 3 POL R/W 2 ME R/W 1 FC1 R/W 0 FC0 R/W LEGEND: R/W = Read/Write; R = Read only Table 5. Configuration Register Field Descriptions BIT 15:12 11 10:9 18 FIELD RN[3:0] CT M[1:0] TYPE R/W R/W R/W RESET DESCRIPTION 1100b Range number field (read or write). The range number field selects the full-scale lux range of the device. The format of this field is the same as the result register exponent field (E[3:0]); see Table 3. When RN[3:0] is set to 1100b (0Ch), the device operates in automatic full-scale setting mode, as described in the Automatic Full-Scale Setting Mode section. In this mode, the automatically chosen range is reported in the result exponent (register 00h, E[3:0]). The device powers up as 1100 in automatic full-scale setting mode. Codes 1101b, 1110b, and 1111b (0Dh, 0Eh, and 0Fh) are reserved for future use. 1b Conversion time field (read or write). The conversion time field determines the length of the light to digital conversion process. The choices are 100 ms and 800 ms. A longer integration time allows for a lower noise measurement. The conversion time also relates to the effective resolution of the data conversion process. The 800-ms conversion time allows for the fully specified lux resolution. The 100-ms conversion time with full-scale ranges above 0101b for E[3:0] in the result and configuration registers also allows for the fully specified lux resolution. The 100-ms conversion time with full-scale ranges below and including 0101b for E[3:0] can reduce the effective result resolution by up to three bits, as a function of the selected full-scale range. Range 0101b reduces by one bit. Ranges 0100b, 0011b, 0010b, and 0001b reduces by two bits. Range 0000b reduces by three bits. The result register format and associated LSB weight does not change as a function of the conversion time. 0 = 100 ms 1 = 800 ms 00b Mode of conversion operation field (read or write). The mode of conversion operation field controls whether the device is operating in continuous conversion, single-shot, or low-power shutdown mode. The default is 00b (shutdown mode), such that upon power-up, the device only consumes operational level power after appropriately programming the device. When single-shot mode is selected by writing 01b to this field, the field continues to read 01b while the device is actively converting. When the single-shot conversion is complete, the mode of conversion operation field is automatically set to 00b and the device is shut down. 00 = Shutdown (default) 01 = Single-shot 10, 11 = Continuous conversions Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 Table 5. Configuration Register Field Descriptions (continued) BIT 8 7 6 FIELD OVF CRF FH TYPE R R R RESET DESCRIPTION 0b Overflow flag field (read-only). The overflow flag field indicates when an overflow condition occurs in the data conversion process, typically because the light illuminating the device exceeds the programmed full-scale range of the device. Under this condition OVF is set to 1, otherwise OVF remains at 0. The field is reevaluated on every measurement. If the full-scale range is manually set (RN[3:0] field < 1100b), the overflow flag field can be set while the result register reports a value less than full-scale. This result occurs if the input light has a temporary high spike level that temporarily overloads the integrating ADC converter circuitry but returns to a level within range before the conversion is complete. Thus, the overflow flag reports a possible error in the conversion process. This behavior is common to integrating-style converters. If the full-scale range is automatically set (RN[3:0] field = 1100b), the only condition that sets the overflow flag field is if the input light is beyond the full-scale level of the entire device. When there is an overflow condition and the full-scale range is not at maximum, the OPT3007 aborts its current conversion, sets the full-scale range to a higher level, and starts a new conversion. The flag is set at the end of the process to indicate a scale increase and that a new measurement is being taken. This process repeats until there is either no overflow condition or until the full-scale range is set to its maximum range. 0b Conversion ready field (read-only). The conversion ready field indicates when a conversion completes. The field is set to 1 at the end of a conversion and is cleared (set to 0) when the configuration register is subsequently read or written with any value except one containing the shutdown mode (mode of operation field, M[1:0] = 00b). Writing a shutdown mode does not affect the state of this field. 0b Flag high field (read-only). The flag high field (FH) identifies that the result of a conversion is larger than a specified level of interest. FH is set to 1 when the result is larger than the level in the high-limit register (register address 03h) for a consecutive number of measurements defined by the fault count field (FC[1:0]). 5 FL R 0b Flag low field (read-only). The flag low field (FL) identifies that the result of a conversion is smaller than a specified level of interest. FL is set to 1 when the result is smaller than the level in the low-limit register (register address 02h) for a consecutive number of measurements defined by the fault count field (FC[1:0]). 4 L R 1b Unused 0b Mask exponent field (read or write). The mask exponent field forces the result register exponent field (register 00h, bits E[3:0]) to 0000b when the full-scale range is manually set, which can simplify the processing of the result register when the full-scale range is manually programmed. This behavior occurs when the mask exponent field is set to 1 and the range number field (RN[3:0]) is set to less than 1100b. Note that the masking is only performed to the result register. 00b Fault count field (read or write). The fault count field instructs the device as to how many consecutive fault events are required to trigger the interrupt reporting mechanisms: the flag high field (FH) and the flag low field (FL). The fault events are described in the flag high field (FH), and flag low field (FL) descriptions. 00 = One fault count (default) 01 = Two fault counts 10 = Four fault counts 11 = Eight fault counts 2 1:0 ME FC[1:0] R/W R/W Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 19 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 7.6.1.1.3 Low-Limit Register (Offset = 02h) [Reset = C0000h] This register sets the lower comparison limit for the interrupt reporting mechanisms: the flag high field (FH) and the flag low field (FL). Figure 24. Low-Limit Register 15 LE3 R/W 14 LE2 R/W 13 LE1 R/W 12 LE0 R/W 11 TL11 R/W 10 TL10 R/W 9 TL9 R/W 8 TL8 R/W 7 TL7 R/W 6 TL6 R/W 5 TL5 R/W 4 TL4 R/W 3 TL3 R/W 2 TL2 R/W 1 TL1 R/W 0 TL0 R/W LEGEND: R/W = Read/Write Table 6. Low-Limit Register Field Descriptions BIT FIELD TYPE RESET DESCRIPTION 15:12 LE[3:0] R/W 0h Exponent. These bits are the exponent bits. Table 7 provides further details. 11:0 TL[11:0] R/W 000h Result. These bits are the result in straight binary coding (zero to full-scale). The format of this register is nearly identical to the format of the result register described in the Result Register. The low-limit register exponent (LE[3:0]) is similar to the result register exponent (E[3:0]). The low-limit register result (TL[11:0]) is similar to result register result (R[11:0]). The equation to translate this register into the lux threshold is given in Equation 3, which is similar to the equation for the result register, Equation 2. lux = 0.01 × (2LE[3:0]) × TL[11:0] (3) Table 7 gives the full-scale range and LSB size as it applies to the low-limit register. The detailed discussion and examples given in for the Result Register apply to the low-limit register as well. Table 7. Full-Scale Range and LSB Size as a Function of Exponent Level LE3 LE2 LE1 LE0 FULL-SCALE RANGE (lux) LSB SIZE (lux per LSB) 0 0 0 0 40.95 0.01 0 0 0 1 81.90 0.02 0 0 1 0 163.80 0.04 0 0 1 1 327.60 0.08 0 1 0 0 655.20 0.16 0 1 0 1 1310.40 0.32 0 1 1 0 2620.80 0.64 0 1 1 1 5241.60 1.28 1 0 0 0 10483.20 2.56 1 0 0 1 20966.40 5.12 1 0 1 0 41932.80 10.24 1 0 1 1 83865.60 20.48 NOTE The result and limit registers are all converted into lux values internally for comparison. These registers can have different exponent fields. However, when using a manually-set full-scale range (configuration register, RN < 0Ch, with mask enable (ME) active), programming the manually-set full-scale range into the LE[3:0] and HE[3:0] fields can simplify the choice of programming the register. This simplification results in the user only having to think about the fractional result and not the exponent part of the result. 20 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 7.6.1.1.4 High-Limit Register (Offset = 03h) [Reset = BFFFh] The high-limit register sets the upper comparison limit for the interrupt reporting mechanisms: the flag high field (FH) and the flag low field (FL). The format of this register is almost identical to the format of the low-limit register (described in the Low-Limit Register) and the result register (described in the Result Register). To explain the similarity in more detail, the high-limit register exponent (HE[3:0]) is similar to the low-limit register exponent (LE[3:0]) and the result register exponent (E[3:0]). The high-limit register result (TH[11:0]) is similar to the lowlimit result (TH[11:0]) and the result register result (R[11:0]). Note that the comparison of the high-limit register with the result register is unaffected by the ME bit. When using a manually-set, full-scale range with the mask enable (ME) active, programming the manually-set, full-scale range into the HE[3:0] bits can simplify the choice of values required to program into this register. The formula to translate this register into lux is similar to Equation 3. The full-scale values are similar to Table 3. Figure 25. High-Limit Register 15 HE3 R/W 14 HE2 R/W 13 HE1 R/W 12 HE0 R/W 11 TH11 R/W 10 TH10 R/W 9 TH9 R/W 8 TH8 R/W 7 TH7 R/W 6 TH6 R/W 5 TH5 R/W 4 TH4 R/W 3 TH3 R/W 2 TH2 R/W 1 TH1 R/W 0 TH0 R/W LEGEND: R/W = Read/Write Table 8. High-Limit Register Field Descriptions BIT FIELD TYPE RESET DESCRIPTION 15:12 HE[3:0] R/W Bh Exponent. These bits are the exponent bits. 11:0 TH[11:0] R/W FFFh Result. These bits are the result in straight binary coding (zero to full-scale). Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 21 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 7.6.1.1.5 Manufacturer ID Register (Offset = 7Eh) [Reset = 5449h] This register is intended to help uniquely identify the device. Figure 26. Manufacturer ID Register 15 ID15 R 14 ID14 R 13 ID13 R 12 ID12 R 11 ID11 R 10 ID10 R 9 ID9 R 8 ID8 R 7 ID7 R 6 ID6 R 5 ID5 R 4 ID4 R 3 ID3 R 2 ID2 R 1 ID1 R 0 ID0 R LEGEND: R = Read only Table 9. Manufacturer ID Register Field Descriptions BIT FIELD TYPE RESET DESCRIPTION 15:0 ID[15:0] R 5449h Manufacturer ID. The manufacturer ID reads 5449h. In ASCII code, this register reads TI. 7.6.1.1.6 Device ID Register (Offset = 7Fh) [Reset = 3001h] This register is also intended to help uniquely identify the device. Figure 27. Device ID Register 15 DID15 R 14 DID14 R 13 DID13 R 12 DID12 R 11 DID11 R 10 DID10 R 9 DID9 R 8 DID8 R 7 DID7 R 6 DID6 R 5 DID5 R 4 DID4 R 3 DID3 R 2 DID2 R 1 DID1 R 0 DID0 R LEGEND: R = Read only Table 10. Device ID Register Field Descriptions 22 BIT FIELD TYPE RESET DESCRIPTION 15:0 DID[15:0] R 3001h Device ID. The device ID reads 3001h. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 8 Application and Implementation NOTE Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality. 8.1 Application Information Ambient light sensors are used in a wide variety of applications that require control as a function of ambient light. Because ambient light sensors nominally match the human eye spectral response, they are superior to photodiodes when the goal is to create an experience for human beings. Very common applications include display optical-intensity control and industrial or home lighting control. There are two categories of interface to the OPT3007: electrical and optical. 8.1.1 Electrical Interface The electrical interface is quite simple, as illustrated in Figure 28. Connect the OPT3007 I2C SDA and SCL pins to the same pins of an applications processor, microcontroller, or other digital processor. Connect pullup resistors between a power supply appropriate for digital communication and the SDA and SCL pins (because they have open-drain output structures).The resistor choice can be optimized in conjunction to the bus capacitance to balance the system speed, power, noise immunity, and other requirements. The power supply and grounding considerations are discussed in the Power-Supply Recommendations section. Although spike suppression is integrated in the SDA and SCL pin circuits, use proper layout practices to minimize the amount of coupling into the communication lines. One possible introduction of noise occurs from capacitively coupling signal edges between the two communication lines themselves. Another possible noise introduction comes from other switching noise sources present in the system, especially for long communication lines. In noisy environments, shield communication lines to reduce the possibility of unintended noise coupling into the digital I/O lines that could be incorrectly interpreted. 8.1.2 Optical Interface The optical interface is physically located on the same side of the device as the electrical interface, as shown in the Sensing Area of the mechanical packages at the end of this data sheet. At a system level, this configuration requires that the light that illuminates the sensor must come through the PCB or FPCB. Typically, the best solution is to create a cutout area in the PCB. Other solutions are possible, but with associated design tradeoffs. This cutout must be carefully designed because the dimensions and tolerances impact the net-system, optical field-of-view performance. The design of this cutout is discussed more in the Design Requirements section. Physical components, such as a plastic housing and a window that allows light from outside of the design to illuminate the sensor (see Figure 29), can help protect the OPT3007 and neighboring circuitry. Sometimes, a dark or opaque window is used to further enhance the visual appeal of the design by hiding the sensor from view. This window material is typically transparent plastic or glass. Any physical component that affects the light that illuminates the sensing area of a light sensor also affects the performance of that light sensor. Therefore, for optimal performance, make sure to understand and control the effect of these components. Design a window width and height to permit light from a sufficient field of view to illuminate the sensor. For best performance, use a field of view of at least ±35°, or ideally ±45° or more. Understanding and designing the field of view is discussed further in application report OPT3001: Ambient Light Sensor Application Guide (SBEA002). The visible-spectrum transmission for dark windows typically ranges between 5% to 30%, but can be less than 1%. Specify a visible-spectrum transmission as low as, but no more than, necessary to achieve sufficient visual appeal because decreased transmission decreases the available light for the sensor to measure. The windows are made dark by either applying an ink to a transparent window material, or including a dye or other optical substance within the window material itself. This attenuating transmission in the visible spectrum of the window creates a ratio between the light on the outside of the design and the light that is measured by the OPT3007. To accurately measure the light outside of the design, compensate the OPT3007 measurement for this ratio. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 23 OPT3007 SBOS864 – AUGUST 2017 www.ti.com Application Information (continued) Ambient light sensors are used to help create ideal lighting experiences for humans; therefore, the matching of the sensor spectral response to that of the human eye response is vital. Infrared light is not visible to the human eye, and can interfere with the measurement of visible light when sensors lack infrared rejection. Therefore, the ratio of visible light to interfering infrared light affects the accuracy of any practical system that represents the human eye. The strong rejection of infrared light by the OPT3007 allows measurements consistent with human perception under high-infrared lighting conditions, such as from incandescent, halogen, or sunlight sources. Although the inks and dyes of dark windows serve their primary purpose of being minimally transmissive to visible light, some inks and dyes can also be very transmissive to infrared light. The use of these inks and dyes further decreases the ratio of visible to infrared light, and thus decreases sensor measurement accuracy. However, because of the excellent infrared rejection of the OPT3007, this effect is minimized, and good results are achieved under a dark window with similar spectral responses to those shown in Figure 31. For best accuracy, avoid grill-like window structures, unless the designer understands the optical effects sufficiently. These grill-like window structures create a nonuniform illumination pattern at the sensor that make light measurement results vary with placement tolerances and angle of incidence of the light. If a grill-like structure is desired, the OPT3007 is an excellent sensor choice because it is minimally sensitive to illumination uniformity issues disrupting the measurement process. Light pipes can appear attractive for aiding in the optomechanical design that brings light to the sensor; however, do not use light pipes with any ambient light sensor unless the system designer fully understands the ramifications of the optical physics of light pipes within the full context of his design and objectives. 8.2 Typical Application Measuring the ambient light with the OPT3007 mounted on a flexible printed-circuit board (FPCB) is described in this section. The schematic for this design is shown in Figure 28. VDD VDD OPT3007 Ambient Light Optical Filter ADC I 2C Interface Digital Processor SCL SCL SDA SDA GND Copyright © 2017, Texas Instruments Incorporated Figure 28. Measuring Ambient Light on an FPCB 24 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 Typical Application (continued) 8.2.1 Design Requirements This design focuses on the field of view, or angular response, of an OPT3007 mounted on an FPCB with an area cut out that permits light to illuminate the sensor. As a result of the geometry of this cutout, the system field of view (angular response) depends on the axis of rotation. One axis of rotation has a less restricted field of view, and the other axis of rotation has a more restricted field of view. The basic requirements of this design are: • Mount the OPT3007 onto an FPCB with a cutout that allows light to illuminate the sensor. • The field of view along the axis of rotation with the less restricted field of view must match the device performance. • The field of view for the more restricted axis of rotation must be minimum of ±30°. Field of view is traditionally defined as the angle at which the angular response is 50% of the maximum value of the system response. 8.2.2 Detailed Design Procedure 8.2.2.1 Optomechanical Design After completing the electrical design (see Figure 28), the next task is the optomechanical design of the FPCB cutout. Design this cutout in conjunction with the tolerance capabilities of the FPCB manufacturer. Or, conversely, choose the FPCB manufacturer for its capabilities of optimally creating this cutout. A semirectangular shape of the cutout, created with a standard FPCB laser, is presented here. There are many alternate approaches with different cost, tolerance, and performance tradeoffs. An image of the created FPCB with the rectangular cutout is shown in Figure 29. The long (vertical) direction of the cutout obviously has no effect on the angular response because any shadows created from the FPCB do not come near the sensor. The long cutout direction defines the axis of rotation with the less restricted field of view. The narrow (horizontal) direction of the cutout, which is limited by the electrical connections to OPT3007, can create shadows that can have a minor impact on the angular response. The narrow cutout direction defines the axis of rotation of the more restricted view. The possibility of shadows are illustrated in Figure 30, a crosssectional diagram showing the OPT3007 device, with the sensing area, soldered to the FPCB with the cutout. Figure 29. Image of FPCB With OPT3007 Mounted, Receiving Light Through the Cutout Device Illuminated Sensor Copper Pillar Electrical Connection Shadowed Sensor Sensing Area Solder FPCB Shadow FPCB Shadow Limiting Point Light entering from 30 degree angle Figure 30. Cross-Sectional Diagram of OPT3007 Soldered to an FPCB With a Cutout, Including Light Entering From an Angle Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 25 OPT3007 SBOS864 – AUGUST 2017 www.ti.com Typical Application (continued) To design the angular response to have greater than 50% response at 30°, the optical mechanisms must be understood. This analysis is simplified by assuming a perfectly rectangular cutout. The concepts for this rectangular cutout apply to nonrectangular cutouts, but require a more complex 3D analysis. The analysis performed here is approximate because the actual cutout is not perfectly rectangular. The net system response is the response of the device without the shadowing effect, multiplied by the percentage of the device that is illuminated, per Equation 4: Net System Response (%) = Device Response (%) × Device Illumination (%) (4) The shadow impacts the percentage of the sensor that can be illuminated, as seen in Figure 30. The percent response of a shadowed sensor is the percent of the sensor that is illuminated. The percent of the sensor that must be illuminated to achieve > 50% response is derived by the sequence of Equation 5 through Equation 7. Net System Response > 50% Device Response × Device Illumination > 50% Device Illumination > 50% / Device Response (5) (6) (7) The device has a 75% response at 30°, as shown in Figure 13, and is a little less than the expected cosine of 30°. The resulting device illumination is shown inEquation 8. Device Illumination > 66% (8) Hence, the 3-dimensional geometry illustrated in Figure 30 must permit greater than 66% of the sensor to be illuminated at a 30° angle of incident light. To quantify the geometry of this design, the post-SMT solder thickness is approximately 37 µm (half the thickness of the pre-SMT solder paste thickness), the copper pillar electrical connection is 7 µm, and the FPCB is 105 µm. Therefore, the shadow limiting point is 37 µm + 7 µm + 105 µm = 149 µm, higher than the sensing surface. The 30° angle shadow extends beyond that shadow limiting point per Equation 9. Shadow = Tan (Illumination_Angle) × Shadow_limiting_height = Tan (30degrees) × 149 µm = 86 µm (9) For this instance of the design and tolerance, the shadow limiting point of FPCB cutout is roughly even with the sensor edge, so 86 µm of the sensor is under shadow. If the shadow limiting point was not even with the sensor edge because of either the design or the tolerances, an extra term is added per the system geometry. Given that the sensor width is 381 µm (per the attached mechanical drawing at the end of this data sheet), the amount of illuminated sensor is 381 µm – 86 µm = 295 µm = 77.4%. The net response at the 30° angle is predicted byEquation 10 Net System Response = Device Response × Device Illumination = 75% × 77.4% = 58% (10) There might be an additional need to put a product casing over the assembly of OPT3007 and the FPCB. The window sizing and placement for such an assembly is discussed in more rigorous detail in application report OPT3001: Ambient Light Sensor Application Guide (SBEA002). 26 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 Typical Application (continued) 8.2.3 Application Curves 1 1 0.9 0.9 0.8 0.8 Normalized Response Normalized Response To validate the angular response of the design, put a light source in a fixed position, allow the device assembly to rotate, and take device measurements at a series of angles. The resulting angular response of this design along the less-restricted rotational axis is shown in Figure 31. The resulting angular response of the morerestricted rotational axis is shown in Figure 32. The response of the device at a 30° angle is approximately 60%, and is very close to the 58% predicted by Equation 10 in the preceding analysis. 0.7 0.6 0.5 0.4 0.3 0.7 0.6 0.5 0.4 0.3 0.2 0.2 0.1 0.1 0 -90 -75 -60 -45 -30 -15 0 15 30 45 Incidence Angle (Degrees) 60 75 90 D010 Figure 31. Angular Response of this FPCB Design Along the Less-Restricted Rotational Axis 0 -90 -75 -60 -45 -30 -15 0 15 30 45 Incidence Angle (Degrees) 60 75 90 D022 Figure 32. Angular Response of this FPCB Design Along the More-Restricted Rotational Axis 8.3 Do's and Don'ts As with any optical product, take special care when handling the OPT3007. The OPT3007 is a piece of active silicon, without the mechanical protection of an epoxy-like package or other reenforcement. This design allows the device to be as thin as possible. Take extra care to handle the device gently in order to not crack or break the device. Use a properly-sized vacuum manipulation tool to handle the device. The optical surface of the device must be kept clean for optimal performance, both when prototyping with the device, and during mass production manufacturing procedures. Keep the optical surface clean of fingerprints, dust, and other optical-inhibiting contaminants. If the optical surface of the device requires cleaning, use a few gentle brushes with a soft swab of deionized water or isopropyl alcohol. Avoid potentially abrasive cleaning and manipulating tools and excessive force that can scratch the optical surface. If the OPT3007 performs less than optimally, inspect the optical surface for dirt, scratches, or other optical artifacts. 9 Power-Supply Recommendations Although the OPT3007 has low sensitivity to power-supply issues, good practices are always recommended. For best performance, the OPT3007 VDD pin must have a stable, low-noise power supply with a 100-nF bypass capacitor close to the device and solid grounding. There are many options for powering the OPT3007 because the device current consumption levels are very low. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 27 OPT3007 SBOS864 – AUGUST 2017 www.ti.com 10 Layout 10.1 Layout Guidelines The PCB layout design for the OPT3007 requires a couple of considerations. The design of the cutout to allow light to illuminate the sensor is a critical part of this design. See the Optomechanical Design section for a more detailed discussion of creating this cutout. The device layout is also critical for optimal SMT assembly. Two types of land pattern pads can be used for this package: solder mask defined pads (SMD) and non-solder mask defined pads (NSMD). SMD pads have a solder mask opening that is smaller than the metal pads, whereas NSMD has a solder mask opening that is larger than the metal pad.Figure 33 illustrates these types of landing-pattern pads. SMD is preferred because it provides a more accurate soldering-pad dimension with the trace connections. For further discussion of SMT and PCB recommendations, see the Soldering and Handling Recommendations section. Figure 33. Soldermask Defined Pad (SMD) and Non-Soldermask Defined Pad (NSMD) Stabilize the power supply with a capacitor placed close to the OPT3007 VDD and GND pins. Note that optically reflective surfaces of components also affect the performance of the design. The three-dimensional geometry of all components and structures around the sensor must be taken into consideration to prevent unexpected results from secondary optical reflections. Placing capacitors and components at a distance of at least twice the height of the component is usually sufficient, although further placement can still achieve good results. The most optimal optical layout is to place all close components on the opposite side of the PCB from the OPT3007. However, this approach may not be practical for the constraints of every design. An example PCB layout with the OPT3007 is shown in Figure 35. 10.2 Soldering and Handling Recommendations The OPT3007 is a very small device with special soldering and handling considerations. See Optomechanical Design for implications of alignment between the device and the cutout area. See Layout Guidelines for considerations of the soldering pads. As with most optical devices, handle the OPT3007 with special care to make sure optical surfaces stay clean and free from damage. See the Do's and Don'ts section for more detailed recommendations. For best optical performance, clean solder flux and any other possible debris after soldering processes. 28 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 Soldering and Handling Recommendations (continued) 10.2.1 Solder Paste For solder-paste deposition, use a stencil-printing process that involves the transfer of solder paste through predefined apertures with the application of pressure. Stencil parameters, such as aperture area ratio and fabrication process, have a significant impact on paste deposition. Cut the stencil apertures using a laser with an electropolish-fabrication method. Taper the stencil aperture walls by 5° to facilitate paste release. Shifting the solder-paste towards the outside of the device minimizes the possibility of solder getting into the device sensing area. See the mechanical packages attached to the end of this data sheet. Use solder paste selection type 4 or higher, no-clean, lead-free solder paste. If solder splatters in the reflow process, choose a solder paste with normal- or low-flux contents, or alter the reflow profile per the Reflow Profile section. 10.2.2 Package Placement Use a pick-and-place nozzle with a size number larger than 0.6 mm. If the placement method is done by programming the component thickness, add 0.04 mm to the actual component thickness so that the package sits halfway into the solder paste. If placement is by force, then choose minimum force no larger than 3N in order to avoid forcing out solder paste, or free falling the package, and to avoid soldering problems such as bridging and solder balling. 10.2.3 Reflow Profile Use the profile in Figure 34, and adjust if necessary. Use a slow solder reflow ramp rate of 1°C to 1.2°C/s to minimize chances of solder splattering onto the sensing area. Figure 34. Recommended Solder Reflow Temperature Profile Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 29 OPT3007 SBOS864 – AUGUST 2017 www.ti.com Soldering and Handling Recommendations (continued) 10.2.4 Special Flexible Printed-Circuit Board (FPCB) Recommendations Special flexible printed-circuit board (FPCB) design recommendations include: • Fabricate per IPC-6013. • Use material of flexible copper clad per IPC 4204/11 (Define polyimide and copper thickness per product application). • Finish: All exposed copper will be electroless Ni immersion gold (ENIG) per IPC 4556. • Solder mask per IPC SM840. • Use a laser to create the cutout for light sensing for better accuracy, and to avoid affecting the soldering pad dimension. Other options, such as punched cutouts, are possible. See the Optomechanical Design section for further discussion ranging from the implications of the device to cutout region size and alignment. The full design must be considered, including the tolerances. To assist the handling of the very thin flexible circuit, design and fabricate a fixture to hold the flexible circuit through the paste-printing, pick-and-place, and reflow processes. Contact the factory for examples of such fixtures. 10.2.5 Rework Process If the OPT3007 must be removed from a PCB, discard the device and do not reattach. To remove the package from the PCB/Flexi cable, heat the solder joints above liquidus temperature. Bake the board at 125°C for 4 hours prior to rework to remove moisture that may crack the PCB or causing delamination. Use a thermal heating profile to remove a package that is close to the profile that mounts the package. Clean the site to remove any excess solder and residue to prepare for installing a new package. Use a mini stencil (localized stencil) to apply solder paste to the land pattern. In case a mini stencil cannot be used because of spacing or other reasons, apply solder paste on the package pads directly, then mount, and reflow. 10.3 Layout Example GND SCL OPT3007 Device Cutout Microcontoller Capacitor VDD SDA Pins B1 and B2 unsoldered The center pads are no connect Figure 35. Example FPCB Layout With the OPT3007 30 Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 OPT3007 www.ti.com SBOS864 – AUGUST 2017 11 Device and Documentation Support 11.1 Documentation Support 11.1.1 Related Documentation For related documentation see the following: • OPT3001: Ambient Light Sensor Application Guide (SBEA002) • OPT3007EVM User's Guide (SBOU181) • QFN/SON PCB Attachment Application Report (SLUA271) 11.2 Receiving Notification of Documentation Updates To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper right corner, click on Alert me to register and receive a weekly digest of any product information that has changed. For change details, review the revision history included in any revised document. 11.3 Community Resources The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of Use. TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help solve problems with fellow engineers. Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and contact information for technical support. 11.4 Trademarks PicoStar, E2E are trademarks of Texas Instruments. All other trademarks are the property of their respective owners. 11.5 Electrostatic Discharge Caution This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. 11.6 Glossary SLYZ022 — TI Glossary. This glossary lists and explains terms, acronyms, and definitions. 12 Mechanical, Packaging, and Orderable Information The following pages include mechanical packaging and orderable information. This information is the most current data available for the designated devices. This data is subject to change without notice and revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation. Submit Documentation Feedback Copyright © 2017, Texas Instruments Incorporated Product Folder Links: OPT3007 31 PACKAGE OPTION ADDENDUM www.ti.com 30-Sep-2017 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (°C) Device Marking (4/5) OPT3007YMFR ACTIVE PICOSTAR YMF 6 3000 Green (RoHS & no Sb/Br) Call TI Level-1-260C-UNLIM -40 to 85 7F OPT3007YMFT ACTIVE PICOSTAR YMF 6 250 Green (RoHS & no Sb/Br) Call TI Level-1-260C-UNLIM -40 to 85 7F (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of