TCS3771 Color Light-To-Digital Converter with Proximity Sensing General Description The TCS3771 family of devices provides red, green, blue, and clear (RGBC) light sensing and proximity detection (when coupled with an external IR LED). They detect light intensity under a variety of lighting conditions and through a variety of attenuation materials. The proximity detection feature allows a large dynamic range of operation for use in short distance detection behind dark glass such as in a cell phone or for longer distance measurements for applications such as presence detection for monitors or laptops. The programmable proximity detection enables continuous measurements across the entire range. In addition, an internal state machine provides the ability to put the device into a low power mode in between RGBC and proximity measurements providing very low average power consumption. The TCS3771 is directly useful in lighting conditions containing minimal IR content such as LED RGB backlight control, reflected LED color sampler, or fluorescent light color temperature detector. With the addition of an IR blocking filter, the device is an excellent ambient light sensor, color temperature monitor, and general purpose color sensor. The proximity function is targeted specifically towards battery-powered mobile devices, LCD monitor, laptop, and flat-panel television applications. In cell phones, the proximity detection can detect when the user positions the phone close to their ear. The device is fast enough to provide proximity information at a high repetition rate needed when answering a phone call. It can also detect both close and far distances so the application can implement more complex algorithms to provide a more robust interface. In laptop or monitor applications, the product is sensitive enough to determine whether a user is in front of the laptop using the keyboard or away from the desk. This provides both improved green power saving capability and the added security to lock the computer when the user is not present. Ordering Information and Content Guide appear at end of datasheet. ams Datasheet [v1-30] 2014-Sep-01 Page 1 Document Feedback TCS3771 − General Description Key Benefits & Features The benefits and features of the TCS3771 are listed below: Figure 1: Added Value of using TCS3771 Benefits Features Single Device reduces board space RGB Color Sensing and Proximity Detection in a Single Device Enables both Correlated Color Temperature and Ambient Light Sensing across wide range of lighting condition applications Color Light Sensing • Programmable Analog Gain, Integration Time, and Interrupt Function with Upper and Lower Thresholds • Resolution Up to 16 bits • Very High Sensitivity - Ideally Suited for Operation Behind Dark Glass • Up to 1,000,000:1 Dynamic Range Enables versatile Infra-red proximity based object detection Proximity Detection • Programmable Number of IR Pulses, Current Sink for the IR LED - No Limiting Resistor Needed, and Interrupt Function with Upper and Lower Thresholds • Covers a 2000:1 Dynamic Range Low power wait state programmability reduces average power consumption Low Power Wait State • 65μA Typical Current • Wait Timer is Programmable from 2.4ms to > 7 seconds Digital interfaces are less susceptible to noise I2C Interface Compatible • Up to 400kHz (I2C Fast Mode) Reduces micro-processor Interrupt Overhead with both up persist and no-persist interrupt thresholds Dedicated Interrupt Pin Enables drop-in and foot-print compatible solutions Pin and Register Set Compatible with the TCS3x7x Family of Devices Reduces board space requirements while simplifying designs Small 2mm × 2.4mm Dual Flat No-Lead Package Low power sleep state reduces average power consumption Sleep Mode - 2.5μA Typical Current Applications The applications of TCS3771 include: • RGB LED Backlight Control • Ambient Color Temperature Sensing • Cell Phone Touch Screen Disable • Notebook/Monitor Security • Automatic Menu Popup • Industrial Process Control • Medical Diagnostics Page 2 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − General Description End Products and Market Segments • HDTVs, Mobile Handsets, Tablets, Laptops, Monitors, PMP (Portable Media Payers) • Medical and Commercial Instrumentation • Consumer Toys • Industrial/Commercial Lighting Block Diagram The functional blocks of this device for reference are shown below: Figure 2: TCS3771 Block Diagram ams Datasheet [v1-30] 2014-Sep-01 Page 3 Document Feedback TCS3771 − Detailed Description Detailed Description The TCS3771 light-to-digital device contains a 4 × 4 photodiode array, integrating amplifiers, ADCs, accumulators, clocks, buffers, comparators, a state machine, and an I 2C interface. The 4 × 4 photodiode array is composed of red-filtered, green-filtered, blue-filtered, and clear photodiodes - four of each type. Four integrating ADCs simultaneously convert the amplified photodiode currents to a digital value providing up to 16 bits of resolution. Upon completion of the conversion cycle, the conversion result is transferred to the data registers. The transfers are double-buffered to ensure that the integrity of the data is maintained. Communication to the device is accomplished through a fast (up to 400kHz), two-wire I2C serial bus for easy connection to a microcontroller or embedded controller. The TCS3771 provides a separate pin for level-style interrupts. When interrupts are enabled and a preset value is exceeded, the interrupt pin is asserted and remains asserted until cleared by the controlling firmware. The interrupt feature simplifies and improves system efficiency by eliminating the need to poll a sensor for a light intensity or proximity value. An interrupt is generated when the value of an RGBC or proximity conversion exceeds either an upper or lower threshold. In addition, a programmable interrupt persistence feature allows the user to determine how many consecutive exceeded thresholds are necessary to trigger an interrupt. Interrupt thresholds and persistence settings are configured independently for both RGBC and proximity. Proximity detection requires only a single external IR LED. An internal LED driver can be configured to provide a constant current sink of 12.5mA, 25mA, 50mA or 100mA of current. No external current limiting resistor is required. The number of proximity LED pulses can be programmed from 1 to 255 pulses. Each pulse has a 14μs period. This LED current coupled with the programmable number of pulses provides a 2000:1 contiguous dynamic range. Page 4 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Pin Assignments The TCS3771 pin assignments are described below: Pin Assignments Figure 3: Pin Diagram of Package FN Dual Flat No-Lead (Top View) Package drawing not to scale. Figure 4: Terminal Functions Terminal Type Description Name No VDD 1 SCL 2 GND 3 LDR 4 O LED driver for proximity emitter - up to 100mA, open drain INT 5 O Interrupt - open drain (active low) SDA 6 I/O I2C serial data I/O terminal - serial data I/O for I2C ams Datasheet [v1-30] 2014-Sep-01 Supply voltage I I2C serial clock input terminal - clock signal for I2C serial data Power supply ground. All voltages are referenced to GND. Page 5 Document Feedback TCS3771 − Absolute Maximum Ratings Absolute Maximum Ratings Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only. Functional operation of the device at these or any other conditions beyond those indicated under “Recommended Operating Conditions” on page 7 is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Figure 5: Absolute Maximum Ratings over Operating Free-Air Temperature Range (unless otherwise noted) Symbol Parameter Min Max Unit 3.8 V -0.5 3.8 V VDD Supply voltage (1) VO Digital output voltage range IO Digital output current -1 20 mA Storage temperature range -40 85 °C 2000 V Tstg ESD tolerance, human body model Note(s) and/or Footnote(s): 1. All voltages are with respect to GND. Page 6 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Electrical Characteristics All limits are guaranteed. The parameters with min and max values are guaranteed with production tests or SQC (Statistical Quality Control) methods. Electrical Characteristics Figure 6: Recommended Operating Conditions Symbol VDD TA Parameter Min Nom Max Unit Supply voltage 2.7 3 3.3 V Operating free-air temperature -30 70 °C Typ Max Unit Active - LDR pulses off 235 330 Wait mode 65 Sleep mode - no I2C activity 2.5 Figure 7: Operating Characteristics, VDD = 3V, TA = 25°C (unless otherwise noted) Symbol IDD VOL Parameter Supply current INT, SDA output low voltage Test Conditions Min μA 10 3mA sink current 0 0.4 6mA sink current 0 0.6 V ILEAK Leakage current, SDA, SCL, INT pins -5 5 μA ILEAK Leakage current, LDR pin -10 +10 μA VIH SCL, SDA input high voltage VIL SCL, SDA input low voltage ams Datasheet [v1-30] 2014-Sep-01 TCS37711 & TCS37715 0.7 VDD TCS37713 & TCS37717 1.25 V TCS37711 & TCS37715 0.3 VDD TCS37713 & TCS37717 0.54 V Page 7 Document Feedback T C S 3 7 7 1 − Electrical Characteristics Figure 8: Optical Characteristics, VDD = 3V, TA = 25°C, Gain = 16, ATIME = 0xF6 (unless otherwise noted) (1) Parameter Re Irradiance responsivity Test Conditions Red Channel Green Channel Blue Channel Clear Channel Unit Min Typ Max Min Typ Max Min Typ Max Min Typ Max λD = 465nm, (2) 0% 15% 10% 42% 65% 88% 19.2 24 28.8 λD = 525nm, (3) 6% 25% 60% 85% 9% 35% 22.4 28 33.6 λD = 625nm, (4) 85% 110% 0% 15% 5% 25% 27.2 34 40.8 counts/ (μW/cm2) Note(s) and/or Footnote(s): 1. The percentage shown represents the ratio of the respective red, green, or blue channel value to the clear channel value. 2. The 465nm input irradiance is supplied by an InGaN light-emitting diode with the following characteristics: dominant wavelength λD = 465nm, spectral halfwidth Δλ½ = 22nm, and luminous efficacy = 75lm/W. 3. The 525nm input irradiance is supplied by an InGaN light-emitting diode with the following characteristics: dominant wavelength λD = 525nm, spectral halfwidth Δλ½ = 35nm, and luminous efficacy = 520lm/W. 4. The 625nm input irradiance is supplied by a AlInGaP light-emitting diode with the following characteristics: dominant wavelength λD = 625nm, spectral halfwidth Δλ½ = 9nm, and luminous efficacy = 155lm/W. Page 8 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Electrical Characteristics Figure 9: RGBC Characteristics, VDD = 3V, TA = 25°C, AGAIN = 16, AEN = 1 (unless otherwise noted) Parameter Test Conditions Dark ADC count value Ee = 0, AGAIN = 60×, ATIME = 0xD6 (100ms) ADC integration time step size ATIME = 0xFF Min Typ Max Unit 0 1 5 counts 2.27 2.4 2.56 ms ADC number of integration steps 1 256 steps ADC counts per step 0 1024 counts 0 65535 counts ADC count value Gain scaling, relative to 1× gain setting ams Datasheet [v1-30] 2014-Sep-01 ATIME = 0xC0 (153.6ms) 4× 3.8 4 4.2 16× 15 16 16.8 60× 58 60 63 % Page 9 Document Feedback TCS3771 − Electrical Characteristics Figure 10: Proximity Characteristics, VDD = 3V, TA = 25°C, Gain = 16, PEN = 1 (unless otherwise noted) Parameter IDD Test Conditions Supply current LDR pulse on ADC conversion time step size PTIME = 0xFF Condition Min Typ Max 3 2.27 Unit mA 2.4 2.56 ms ADC number of integration steps 1 256 steps ADC counts per step 0 1023 counts IR LED pulse count 0 255 pulses LED pulse period Two or more pulses LED pulse width - LED on time PDRIVE = 0 LED drive current ISINK sink current @ 600mV, LDR pin 80 14 μs 6.3 μs 106 PDRIVE = 1 50 PDRIVE = 2 25 PDRIVE = 3 12.5 132 mA Dark count value Ee = 0, PTIME = 0xFB, PPULSE = 2 Red channel λP = 850nm, Ee = 45.3μW/cm2, Clear channel λP = 850nm, Ee = 45.3μW/cm2, PTIME = 0xFB, PPULSE = 2 (1) PTIME = 0xFB, PPULSE = 2 (1) 900 counts 1000 3000 counts 1000 3000 counts Operating distance (2) 30 inches Note(s) and/or Footnote(s): 1. The specified light intensity is 100% modulated by the pulse output of the device so that during the pulse output low time, the light intensity is at the specified level, and 0 otherwise. 2. Proximity Operating Distance is dependent upon emitter properties and the reflective properties of the proximity surface. The nominal value shown uses an IR emitter with a peak wavelength of 850nm and a 20° half angle. The proximity surface used is a 90% reflective (white surface) 16 × 20-inch Kodak Gray Card. 60mw/SR, 100mA, 64 pulses, open view (no glass). Greater distances are achievable with appropriate system considerations. Figure 11: Wait Characteristics, VDD = 3V, TA = 25°C, Gain = 16, WEN = 1 (unless otherwise noted) Parameter Wait step size Wait number of steps Page 10 Document Feedback Test Conditions WTIME = 0xFF Channel Min Typ Max Unit 2.27 2.4 2.56 ms 256 steps 1 ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Electrical Characteristics Figure 12: AC Electrical Characteristics, VDD = 3V, TA = 25°C (unless otherwise noted) Parameter (1) Symbol Test Conditions Min Typ Max Unit 400 kHz f(SCL) Clock frequency (I2C only) t(BUF) Bus free time between start and stop condition 1.3 μs t(HDSTA) Hold time after (repeated) start condition. After this period, the first clock is generated. 0.6 μs t(SUSTA) Repeated start condition setup time 0.6 μs t(SUSTO) Stop condition setup time 0.6 μs t(HDDAT) Data hold time 0 μs t(SUDAT) Data setup time 100 ns t(LOW) SCL clock low period 1.3 μs t(HIGH) SCL clock high period 0.6 μs tF Clock/data fall time 300 ns tR Clock/data rise time 300 ns Ci Input pin capacitance 10 pF 0 Note(s) and/or Footnote(s): 1. Specified by design and characterization; not production tested. ams Datasheet [v1-30] 2014-Sep-01 Page 11 Document Feedback TCS3771 − Parameter Measurement Information Parameter Measurement Information Figure 13: Timing Diagrams Page 12 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Typical Characteristics Typical Characteristics Relative Responsivity Figure 14: Photodiode Spectral Responsivity λ - Wavelength - nm LDR Current - mA Figure 15: Typical LDR Current vs. Voltage LDR Voltage - V ams Datasheet [v1-30] 2014-Sep-01 Page 13 Document Feedback TCS3771 − Typical Characteristics IDD Normalized @ 3V, 25°C Figure 16: Normalized IDD vs. VDD and Temperature VDD - V Normalized Responsivity Figure 17: Normalized Responsivity vs. Angular Displacement Θ - Angular Displacement - ° Page 14 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Typical Characteristics Temperature Coefficient - ppm/°C Figure 18: Responsivity Temperature Coefficient λ - Wavelength - nm ams Datasheet [v1-30] 2014-Sep-01 Page 15 Document Feedback TCS3771 − Principles of Operation Principles of Operation System State Machine The TCS3771 provides control of RGBC, proximity detection, and power management functionality through an internal state machine (Figure 19). After a power-on-reset, the device is in the sleep mode. As soon as the PON bit is set, the device will move to the start state. It will then continue through the Prox, Wait, and RGBC states. If these states are enabled, the device will execute each function. If the PON bit is set to 0, the state machine will continue until all conversions are completed and then go into a low power sleep mode. Figure 19: Simplified State Diagram Note(s): In this document, the nomenclature uses the bit field name in italics followed by the register number and bit number to allow the user to easily identify the register and bit that controls the function. For example, the power on (PON) is in register 0, bit 0. This is represented as PON (r0:b0). Page 16 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation RGBC Operation The RGBC engine contains RGBC gain control (AGAIN) and four integrating analog-to-digital converters (ADC) for the RGBC photodiodes. The RGBC integration time (ATIME) impacts both the resolution and the sensitivity of the RGBC reading. Integration of all four channels occurs simultaneously and upon completion of the conversion cycle, the results are transferred to the color data registers. This data is also referred to as channel count. The transfers are double-buffered to ensure that invalid data is not read during the transfer. After the transfer, the device automatically moves to the next state in accordance with the configured state machine. Figure 20: RGBC Operation The registers for programming the integration and wait times are a 2’s compliment values. The actual time can be calculated as follows: ATIME = 256 - Integration Time / 2.4ms Inversely, the time can be calculated from the register value as follows: Integration Time = 2.4ms × (256 - ATIME) For example, if a 100-ms integration time is needed, the device needs to be programmed to: 256 - (100 / 2.4) = 256 - 42 = 214 = 0xD6 Conversely, the programmed value of 0xC0 would correspond to: (256 - 0xC0) × 2.4 = 64 × 2.4 = 154ms ams Datasheet [v1-30] 2014-Sep-01 Page 17 Document Feedback TCS3771 − Principles of Operation Proximity Detection Proximity sensing uses an external light source (generally an infrared emitter) to emit light, which is then viewed by the integrated light detector to measure the amount of reflected light when an object is in the light path (Figure 21). The amount of light detected from a reflected surface can then be used to determine an object’s proximity to the sensor. Figure 21: Proximity Detection The TCS3771 has controls for the number of IR pulses (PPCOUNT), the integration time (PTIME), the LED drive current (PDRIVE) and the photodiode configuration (PDIODE). The photodiode configuration can be set to red diode (recommended), clear diode, or a combination of both diodes. At the end of the integration cycle, the results are latched into the proximity data (PDATA) register. Figure 22: Proximity Detection Operation Page 18 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation The LED drive current is controlled by a regulated current sink on the LDR pin. This feature eliminates the need to use a current limiting resistor to control LED current. The LED drive current can be configured for 12.5mA, 25mA, 50mA, or 100mA. For higher LED drive requirements, an external P-FET transistor can be used to control the LED current. The number of LED pulses can be programmed to any value between 1 and 255 pulses as needed. Increasing the number of LED pulses at a given current will increase the sensor sensitivity. Sensitivity grows by the square root of the number of pulses. Each pulse has a 14μs period. Figure 23: Proximity IR LED Waveform The proximity integration time (PTIME) is the period of time that the internal ADC converts the analog signal to a digital count. It is recommend that this be set to a minimum of PTIME = 0xFF or 2.4ms. ams Datasheet [v1-30] 2014-Sep-01 Page 19 Document Feedback TCS3771 − Principles of Operation The combination of LED power and number of pulses can be used to control the distance at which the sensor can detect proximity. Figure 24 shows an example of the distances covered with settings such that each curve covers 2× the distance. Counts up to 64 pulses provide a 16× range. Figure 24: Proximity ADC Count vs. Relative Distance Interrupts The interrupt feature simplifies and improves system efficiency by eliminating the need to poll the sensor for light intensity or proximity values outside of a user-defined range. While the interrupt function is always enabled and it’s status is available in the status register (0x13), the output of the interrupt state can be enabled using the proximity interrupt enable (PIEN) or RGBC interrupt enable (AIEN) fields in the Enable Register (0x00). Four 16-bit interrupt threshold registers allow the user to set limits below and above a desired light level and proximity range. An interrupt can be generated when the RGBC Clear data (CDATA) falls outside of the desired light level range, as determined by the values in the RGBC interrupt low threshold registers (AILTx) and RGBC interrupt high threshold registers (AIHTx). Likewise, an out-of-range proximity interrupt can be generated when the proximity data (PDATA) falls below the Page 20 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation proximity interrupt low threshold (PILTx) or exceeds the proximity interrupt high threshold (PIHTx). It is important to note that the low threshold value must be less than the high threshold value for proper operation. To further control when an interrupt occurs, the device provides a persistence filter. The persistence filter allows the user to specify the number of consecutive out-of-range RGBC or proximity occurrences before an interrupt is generated. The persistence register (0x0C) allows the user to set the RGBC persistence (APERS) and the proximity persistence (PPERS) values. See the persistence register for details on the persistence filter values. Once the persistence filter generates an interrupt, it will continue until a special function interrupt clear command is received (see “Command Register” on page 26). Figure 25: Programmable Interrupt ams Datasheet [v1-30] 2014-Sep-01 Page 21 Document Feedback TCS3771 − Principles of Operation State Diagram Figure 26 shows a more detailed flow for the state machine. The device starts in the sleep mode. The PON bit is written to enable the device. A 2.4ms delay will occur before entering the start state. If the PEN bit is set, the state machine will step through the proximity states of proximity accumulate and then proximity ADC conversion. As soon as the conversion is complete, the state machine will move to the following state. If the WEN bit is set, the state machine will then cycle through the wait state. If the WLONG bit is set, the wait cycles are extended by 12× over normal operation. When the wait counter terminates, the state machine will step to the RGBC state. The AEN should always be set, even in proximity-only operation. In this case, a minimum of 1 integration time step should be programmed. The RGBC state machine will continue until it reaches the terminal count at which point the data will be latched in the RGBC register and the interrupt set, if enabled. Figure 26: Expanded State Diagram Page 22 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation I 2 C Protocol Interface and control are accomplished through an I 2C serial compatible interface (standard or fast mode) to a set of registers that provide access to device control functions and output data. The devices support the 7-bit I 2C addressing protocol. The I 2C standard provides for three types of bus transaction: read, write, and a combined protocol (Figure 27). During a write operation, the first byte written is a command byte followed by data. In a combined protocol, the first byte written is the command byte followed by reading a series of bytes. If a read command is issued, the register address from the previous command will be used for data access. Likewise, if the MSB of the command is not set, the device will write a series of bytes at the address stored in the last valid command with a register address. The command byte contains either control information or a 5-bit register address. The control commands can also be used to clear interrupts. The I 2C bus protocol was developed by Philips (now NXP). For a complete description of the I2C protocol, please review the NXP I 2C design specification at http://www.i2c-bus.org/references. Figure 27: I2C Protocols A Acknowledge (0) N Not Acknowledged (1) P Stop Condition R Read (1) S Start Condition Sr Repeated Start Condition W Write (0) … Continuation of protocol Master-to-Slave Slave-to-Master 1 7 S Slave Address 1 1 W A 8 1 8 Command Code A Data Byte 1 1 A ... P I2C Write Protocol 1 7 1 1 8 1 8 S Slave Address R A Data A Data 1 1 A ... P I2C Read Protocol 1 7 S Slave Address 1 1 W A 8 Command Code 1 1 A Sr 7 1 1 Slave Address R A 8 Data A Data 1 1 A ... P I2C Read Protocol - Combined Format ams Datasheet [v1-30] 2014-Sep-01 Page 23 Document Feedback TCS3771 − Principles of Operation Register Set The TCS3771 is controlled and monitored by data registers and a command register accessed through the serial interface. These registers provide for a variety of control functions and can be read to determine results of the ADC conversions. The Register Set is summarized in Figure 28. Figure 28: Register Address Address Register Name R/W -- COMMAND W 0x00 ENABLE 0x01 Register Function Reset Value Specifies register address 0x00 R/W Enables states and interrupts 0x00 ATIME R/W RGBC ADC time 0xFF 0x02 PTIME R/W Proximity ADC time 0xFF 0x03 WTIME R/W Wait time 0xFF 0x04 AILTL R/W RGBC interrupt low threshold low byte 0x00 0x05 AILTH R/W RGBC interrupt low threshold high byte 0x00 0x06 AIHTL R/W RGBC interrupt high threshold low byte 0x00 0x07 AIHTH R/W RGBC interrupt high threshold high byte 0x00 0x08 PILTL R/W Proximity interrupt low threshold low byte 0x00 0x09 PILTH R/W Proximity interrupt low threshold high byte 0x00 0x0A PIHTL R/W Proximity interrupt high threshold low byte 0x00 0x0B PIHTH R/W Proximity interrupt high threshold high byte 0x00 0x0C PERS R/W Interrupt persistence filters 0x00 0x0D CONFIG R/W Configuration 0x00 0x0E PPCOUNT R/W Proximity pulse count 0x00 0x0F CONTROL R/W Gain control register 0x00 0x12 ID R Device ID 0x13 STATUS R Device status 0x00 0x14 CDATA R Clear ADC low data register 0x00 0x15 CDATAH R Clear ADC high data register 0x00 0x16 RDATA R Red ADC low data register 0x00 0x17 RDATAH R Red ADC high data register 0x00 0x18 GDATA R Green ADC low data register 0x00 Page 24 Document Feedback ID ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation Address Register Name R/W Register Function Reset Value 0x19 GDATAH R Green ADC high data register 0x00 0x1A BDATA R Blue ADC low data register 0x00 0x1B BDATAH R Blue ADC high data register 0x00 0x1C PDATA R Proximity ADC low data register 0x00 0x1D PDATAH R Proximity ADC high data register 0x00 The mechanics of accessing a specific register depends on the specific protocol used. See the section on I 2C protocols on the previous pages. In general, the Command register is written first to specify the specific control/status register for following read/write operations. ams Datasheet [v1-30] 2014-Sep-01 Page 25 Document Feedback TCS3771 − Principles of Operation Command Register The Command Registers specifies the address of the target register for future write and read operations. Figure 29: Command Register 7 6 COMMAND 5 4 TYPE Field Bits COMMAND 7 3 2 1 0 ADD Description Select Command Register. Must write as 1 when addressing Command Register. Selects type of transaction to follow in subsequent data transfers: TYPE 6:5 Field Value Integration Time 00 Repeated byte protocol transaction 01 Auto-increment protocol transaction 10 Reserved - Do not use 11 Special function - See description below Byte protocol will repeatedly read the same register with each data access. Block protocol will provide auto-increment function to read successive bytes. Address field/special function field. Depending on the transaction type, see above, this field either specifies a special function command or selects the specific control-status-register for following write and read transactions. The field values listed below apply only to special function commands: ADD 4:0 Field Value Read Value 00000 Normal - no action 00101 Proximity interrupt clear 00110 RGBC interrupt clear 00111 Proximity and RGBC interrupt clear other Reserved — Do not write RGBC/Proximity Interrupt Clear. Clears any pending RGBC/Proximity interrupt. This special function is self clearing. Page 26 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation Enable Register (0x00) The Enable Register is used primarily to power the TCS3771 device on and off, and enable functions and interrupts as shown in Figure 30. Figure 30: Enable Register 7 6 Reserved 5 4 3 2 1 0 PIEN AIEN WEN PEN AEN PON Field Bits Reserved 7:6 PIEN 5 Proximity interrupt enable. When asserted, permits proximity interrupts to be generated. AIEN 4 RGBC interrupt enable. When asserted, permits RGBC interrupts to be generated. WEN 3 Wait enable. This bit activates the wait feature. Writing a 1 activates the wait timer. Writing a 0 disables the wait timer. PEN 2 Proximity enable. This bit activates the proximity function. Writing a 1 enables proximity. Writing a 0 disables proximity. AEN 1 RGBC enable. This bit actives the two-channel ADC. Writing a 1 activates the RGBC. Writing a 0 disables the RGBC. 0 Power ON. This bit activates the internal oscillator to permit the timers and ADC channels to operate. Writing a 1 activates the oscillator. Writing a 0 disables the oscillator. During reads and writes over the I2C interface, this bit is temporarily overridden and the oscillator is enabled, independent of the state of PON. PON (1) Description Reserved. Write as 0. Note(s) and/or Footnote(s): 1. A minimum interval of 2.4ms must pass after PON is asserted before either a proximity or an RGBC can be initiated. This required time is enforced by the hardware in cases where the firmware does not provide it. ams Datasheet [v1-30] 2014-Sep-01 Page 27 Document Feedback TCS3771 − Principles of Operation RGBC Timing Register (0x01) The RGBC Timing Register controls the internal integration time of the RGBC clear and IR channel ADCs in 2.4ms increments. Figure 31: RGBC Timing Register Field ATIME Bits Description Value INTEG_CYCLES Time Max Count 0xFF 1 2.4ms 1024 0xF6 10 24ms 10240 0xD6 42 101ms 43008 0xAD 64 154ms 65535 0x00 256 614ms 65535 7:0 Proximity Time Control Register (0x02) The Proximity Timing Register controls the integration time of the proximity ADC in 2.4ms increments. It is recommended that this register be programmed to a value of 0xFF (1 cycle, 1023 bits). Max Prox Count = ((256 - PTIME) × 1024)) - 1 up to a maximum of 65535 Figure 32: Proximity Time Control Register Field Bits PTIME 7:0 Page 28 Document Feedback Description Value INTEG_CYCLES Time Max Count 0xFF 1 2.4ms 1023 ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation Wait Time Register (0x03) Wait time is set 2.4ms increments unless the WLONG bit is asserted in which case the wait times are 12× longer. WTIME is programmed as a 2’s complement number. Figure 33: Wait Time Register Field WTIME Bits Description Register Value Wait Time Time (WLONG = 0) Time (WLONG = 1) 0xFF 1 2.4ms 0.029 sec 0xAB 85 204ms 2.45 sec 0x00 256 614ms 7.4 sec 7:0 RGBC Interrupt Threshold Registers (0x04 − 0x07) The RGBC Interrupt Threshold Registers provides the values to be used as the high and low trigger points for the comparison function for interrupt generation. If the value generated by the clear channel crosses below the lower threshold specified, or above the higher threshold, an interrupt is asserted on the interrupt pin. Figure 34: RGBC Interrupt Threshold Registers Register Address Bits AILTL 0x04 7:0 RGBC clear channel low threshold lower byte AILTH 0x05 7:0 RGBC clear channel low threshold upper byte AIHTL 0x06 7:0 RGBC clear channel high threshold lower byte AIHTH 0x07 7:0 RGBC clear channel high threshold upper byte ams Datasheet [v1-30] 2014-Sep-01 Description Page 29 Document Feedback TCS3771 − Principles of Operation Proximity Interrupt Threshold Registers (0x08 − 0x0B) The Proximity Interrupt Threshold Registers provide the values to be used as the high and low trigger points for the comparison function for interrupt generation. If the value generated by proximity channel crosses below the lower threshold specified, or above the higher threshold, an interrupt is signaled to the host processor. Figure 35: Proximity Interrupt Threshold Register Register Address Bits PILTL 0x08 7:0 Proximity ADC channel low threshold lower byte PILTH 0x09 7:0 Proximity ADC channel low threshold upper byte PIHTL 0x0A 7:0 Proximity ADC channel high threshold lower byte PIHTH 0x0B 7:0 Proximity ADC channel high threshold upper byte Page 30 Document Feedback Description ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation Persistence Register (0x0C) The Persistence Register controls the filtering interrupt capabilities of the device. Configurable filtering is provided to allow interrupts to be generated after each integration cycle or if the integration has produced a result that is outside of the values specified by the threshold register for some specified amount of time. Separate filtering is provided for proximity and the RGBC clear channel. Figure 36: Persistence Register 7 6 5 4 3 2 PPERS Field 1 0 APERS Bits Description Proximity interrupt persistence. Controls rate of proximity interrupt to the host processor. PPERS ams Datasheet [v1-30] 2014-Sep-01 7:4 Field Value Meaning Interrupt Persistence Function 0000 ---- 0001 1 1 proximity value out of range 0010 2 2 consecutive proximity values out of range .... .... .... 1111 15 15 consecutive proximity values out of range Every proximity cycle generates an interrupt Page 31 Document Feedback TCS3771 − Principles of Operation Field Bits Description Interrupt persistence. Controls rate of interrupt to the host processor. APERS Page 32 Document Feedback Field Value Meaning Interrupt Persistence Function 0000 Every 0001 1 1 clear channel value outside of threshold range 0010 2 2 clear channel consecutive values out of range 0011 3 3 clear channel consecutive values out of range 0100 5 5 clear channel consecutive values out of range 0101 10 10 clear channel consecutive values out of range 0110 15 15 clear channel consecutive values out of range 0111 20 20 clear channel consecutive values out of range 1000 25 25 clear channel consecutive values out of range 1001 30 30 clear channel consecutive values out of range 1010 35 35 clear channel consecutive values out of range 1011 40 40 clear channel consecutive values out of range 1100 45 45 clear channel consecutive values out of range 1101 50 50 clear channel consecutive values out of range 1110 55 55 clear channel consecutive values out of range 1111 60 60 clear channel consecutive values out of range Every RGBC cycle generates an interrupt 3:0 ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation Configuration Register (0x0D) The Configuration Register sets the wait long time. Figure 37: Configuration Register 7 6 5 4 3 2 Reserved 1 0 WLONG Reserved Field Bits Description Reserved 7:2 WLONG 1 Wait Long. When asserted, the wait cycles are increased by a factor 12× from that programmed in the WTIME register. Reserved 0 Reserved. Write as 0. Reserved. Write as 0. Proximity Pulse Count Register (0x0E) The Proximity Pulse Count Register sets the number of proximity pulses that will be transmitted. When proximity detection is enabled, a proximity detect cycle occurs after each RGBC cycle. PPULSE defines the number of pulses to be transmitted. Note(s): The ATIME register will be used to time the interval between proximity detection events even if the RGBC function is disabled. Figure 38: Proximity Pulse Count Register 7 6 5 4 3 2 1 0 PPULSE Field Bits Description PPULSE 7:0 Proximity Pulse Count. Specifies the number of proximity pulses to be generated. ams Datasheet [v1-30] 2014-Sep-01 Page 33 Document Feedback TCS3771 − Principles of Operation Control Register (0x0F) The Control Register provides eight bits of miscellaneous control to the analog block. These bits typically control functions such as gain settings and/or diode selection. Figure 39: Control Register 7 6 PDRIVE Field 5 4 3 PDIODE Bits 2 1 Reserved 0 AGAIN Description LED Drive Strength. PDRIVE Field Value LED Strength 00 100mA 01 50mA 10 25mA 11 12.5mA 7:6 Proximity Diode Select. Field Value PDIODE Reserved Diode Selection 00 Reserved 01 Proximity uses the clear (broadband) diode 10 Proximity uses the IR diode 11 Proximity uses both the clear diode and the red diode 5:4 3:2 Reserved. Write bits as 0. RGBC Gain Control. AGAIN Page 34 Document Feedback Field Value RGBC Gain Value 00 1× gain 01 4× gain 10 16× gain 11 60× gain 1:0 ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Principles of Operation ID Register (0x12) The ID Register provides the value for the part number. The ID Register is a read-only register. Figure 40: ID Register 7 6 5 4 3 2 1 0 ID Field Bits ID 7:0 Description 0x10 = TCS37711 & TCS37715 Part number identification 0x19 = TCS37713 & TCS37717 Status Register (0x13) The Status Register provides the internal status of the device. This register is read only. Figure 41: Status Register 7 6 Reserved 5 4 PINT AINT 3 2 Reserved 1 0 PVALID AVALID Field Bits Reserved 7:6 PINT 5 Proximity Interrupt AINT 4 RGBC clear channel Interrupt Reserved 3:2 PVALID 1 Proximity Valid. Indicates that a RGBC cycle has completed since AEN was asserted. AVALID 0 RGBC Valid. Indicates that the RGBC channels have completed an integration cycle. ams Datasheet [v1-30] 2014-Sep-01 Description Reserved Reserved Page 35 Document Feedback TCS3771 − Principles of Operation RGBC Channel Data Registers (0x14 − 0x1B) Clear, red, green, and blue data is stored as 16-bit values. To ensure the data is read correctly, a two-byte read I2C transaction should be used with a read word protocol bit set in the Command Register. With this operation, when the lower byte register is read, the upper eight bits are stored into a shadow register, which is read by a subsequent read to the upper byte. The upper register will read the correct value even if additional ADC integration cycles end between the reading of the lower and upper registers. Figure 42: ADC Channel Data Registers Register Address Bits Description CDATA 0x14 7:0 Clear data low byte CDATAH 0x15 7:0 Clear data high byte RDATA 0x16 7:0 Red data low byte RDATAH 0x17 7:0 Red data high byte GDATA 0x18 7:0 Green data low byte GDATAH 0x19 7:0 Green data high byte BDATA 0x1A 7:0 Blue data low byte BDATAH 0x1B 7:0 Blue data high byte Proximity Data Registers (0x1C − 0x1D) Proximity data is stored as a 16-bit value. To ensure the data is read correctly, a two-byte read I2C transaction should be used with a read word protocol bit set in the Command Register. With this operation, when the lower byte register is read, the upper eight bits are stored into a shadow register, which is read by a subsequent read to the upper byte. The upper register will read the correct value even if additional ADC integration cycles end between the reading of the lower and upper registers. Figure 43: PDATA Registers Register Address Bits PDATA 0x1C 7:0 Proximity data low byte PDATAH 0x1D 7:0 Proximity data high byte Page 36 Document Feedback Description ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Application Information Application Information LED Driver Pin with Proximity Detection In a proximity sensing system, the IR LED can be pulsed by the TCS3771 with more than 100mA of rapidly switching current, therefore, a few design considerations must be kept in mind to get the best performance. The key goal is to reduce the power supply noise coupled back into the device during the LED pulses. The first recommendation is to use two power supplies; one for the device V DD and the other for the IR LED. In many systems, there is a quiet analog supply and a noisy digital supply. By connecting the quiet supply to the V DD pin and the noisy supply to the LED, the key goal can be meet. Place a 1μF low-ESR decoupling capacitor as close as possible to the V DD pin and another at the LED anode, and a 22μF capacitor at the output of the LED voltage regulator to supply the 100mA current surge. Figure 44: Proximity Sensing Using Separate Power Supplies If it is not possible to provide two separate power supplies, the device can be operated from a single supply. A 22Ω resistor in series with the V DD supply line and a 1μF low ESR capacitor effectively filter any power supply noise. The previous capacitor placement considerations apply. Figure 45: Proximity Sensing Using Single Power Supply ams Datasheet [v1-30] 2014-Sep-01 Page 37 Document Feedback TCS3771 − Application Information V BUS in the above figures refers to the I 2C bus voltage which is either V DD or 1.8V. Be sure to apply the specified I 2C bus voltage shown in the Available Options table for the specific device being used. The I 2C signals and the Interrupt are open-drain outputs and require pull−up resistors. The pull-up resistor (RP) value is a function of the I 2C bus speed, the I 2C bus voltage, and the capacitive load. The ams EVM running at 400kbps, uses 1.5kΩ resistors. A 10kΩ pull-up resistor (RPI) can be used for the interrupt line. PCB Pad Layout Suggested PCB pad layout guidelines for the Dual Flat No-Lead (FN) surface mount package are shown in Figure 46. Figure 46: Suggested FN Package PCB Layout Note(s) and/or Footnote(s): 1. All linear dimensions are in millimeters. 2. This drawing is subject to change without notice. 3. Pads can be extended further if hand soldering is needed. Page 38 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Packaging Mechanical Data Packaging Mechanical Data Figure 47: Package FN - Dual Flat No-Lead Packaging Configuration Green RoHS Note(s) and/or Footnote(s): 1. All linear dimensions are in micrometers. 2. The die is centered within the package within a tolerance of ±75μm. 3. Package top surface is molded with an electrically nonconductive clear plastic compound having an index of refraction of 1.55. 4. Contact finish is copper alloy A194 with pre-plated NiPdAu lead finish. 5. This package contains no lead (Pb). 6. This drawing is subject to change without notice. ams Datasheet [v1-30] 2014-Sep-01 Page 39 Document Feedback TCS3771 − Packaging Mechanical Data Figure 48: Package FN Carrier Tape Note(s) and/or Footnote(s): 1. All linear dimensions are in millimeters. Dimension tolerance is ±0.10mm unless otherwise noted. 2. The dimensions on this drawing are for illustrative purposes only. Dimensions of an actual carrier may vary slightly. 3. Symbols on drawing Ao, Bo, and Ko are defined in ANSI EIA Standard 481-B 2001. 4. Each reel is 178 millimeters in diameter and contains 3500 parts. 5. ams AG packaging tape and reel conform to the requirements of EIA Standard 481-B. 6. In accordance with EIA standard, device pin 1 is located next to the sprocket holes in the tape. 7. This drawing is subject to change without notice. Page 40 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Manufacturing Information Manufacturing Information The FN package has been tested and has demonstrated an ability to be reflow soldered to a PCB substrate. The solder reflow profile describes the expected maximum heat exposure of components during the solder reflow process of product on a PCB. Temperature is measured on top of component. The components should be limited to a maximum of three passes through this solder reflow profile. Figure 49: TCS310x Solder Reflow Profile Parameter Reference Average temperature gradient in preheating TCS310x 2.5°C/sec tsoak 2 to 3 minutes Time above 217°C (T1) t1 Max 60 sec Time above 230°C (T2) t2 Max 50 sec Time above Tpeak - 10°C (T3) t3 Max 10 sec Peak temperature in reflow Tpeak 260° C Soak time Temperature gradient in cooling Max -5°C/sec Figure 50: Solder Reflow Profile Graph Note(s) and/or Footnote(s): 1. Not to scale - for reference only. ams Datasheet [v1-30] 2014-Sep-01 Page 41 Document Feedback TCS3771 − Manufacturing Information Moisture Sensitivity Optical characteristics of the device can be adversely affected during the soldering process by the release and vaporization of moisture that has been previously absorbed into the package. To ensure the package contains the smallest amount of absorbed moisture possible, each device is dry-baked prior to being packed for shipping. Devices are packed in a sealed aluminized envelope called a moisture barrier bag with silica gel to protect them from ambient moisture during shipping, handling, and storage before use. The FN package has been assigned a moisture sensitivity level of MSL 3 and the devices should be stored under the following conditions: • Temperature Range: 5°C to 50°C • Relative Humidity: 60% maximum • Total Time: 12 months from the date code on the aluminized envelope - if unopened • Opened Time: 168 hours or fewer Rebaking will be required if the devices have been stored unopened for more than 12 months or if the aluminized envelope has been open for more than 168 hours. If rebaking is required, it should be done at 50°C for 12 hours. Page 42 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Ordering & Contact Information Ordering & Contact Information Figure 51: Ordering Information Device Address Package - Leads Interface Description Ordering Number TCS37711 (1) 0x39 FN-6 I2C Vbus = VDD Interface TCS37711FN TCS37713 (1) 0x39 FN-6 I2C Vbus = 1.8V Interface TCS37713FN TCS37715 0x29 FN-6 I2C Vbus = VDD Interface TCS37715FN TCS37717 0x29 FN-6 I2C Vbus = 1.8V Interface TCS37717FN Note(s) and/or Footnote(s): 1. Contact ams AG for availability. Buy our products or get free samples online at: www.ams.com/ICdirect Technical Support is available at: www.ams.com/Technical-Support Provide feedback about this document at: www.ams.com/Document-Feedback For further information and requests, e-mail us at: [email protected] For sales offices, distributors and representatives, please visit: www.ams.com/contact Headquarters ams AG Tobelbaderstrasse 30 8141 Unterpremstaetten Austria, Europe Tel: +43 (0) 3136 500 0 Website: www.ams.com ams Datasheet [v1-30] 2014-Sep-01 Page 43 Document Feedback TCS3771 − RoHS Compliant & ams Green Statement RoHS Compliant & ams Green Statement RoHS: The term RoHS compliant means that ams AG products fully comply with current RoHS directives. Our semiconductor products do not contain any chemicals for all 6 substance categories, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, RoHS compliant products are suitable for use in specified lead-free processes. ams Green (RoHS compliant and no Sb/Br): ams Green defines that in addition to RoHS compliance, our products are free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material). Important Information: The information provided in this statement represents ams AG knowledge and belief as of the date that it is provided. ams AG bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. ams AG has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. ams AG and ams AG suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. Page 44 Document Feedback ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Copyrights & Disclaimer Copyrights & Disclaimer Copyright ams AG, Tobelbader Strasse 30, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. Devices sold by ams AG are covered by the warranty and patent indemnification provisions appearing in its General Terms of Trade. ams AG makes no warranty, express, statutory, implied, or by description regarding the information set forth herein. ams AG reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with ams AG for current information. This product is intended for use in commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment are specifically not recommended without additional processing by ams AG for each application. This product is provided by ams AG “AS IS” and any express or implied warranties, including, but not limited to the implied warranties of merchantability and fitness for a particular purpose are disclaimed. ams AG shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of ams AG rendering of technical or other services. ams Datasheet [v1-30] 2014-Sep-01 Page 45 Document Feedback TCS3771 − Document Status Document Status Document Status Product Preview Preliminary Datasheet Datasheet Datasheet (discontinued) Page 46 Document Feedback Product Status Definition Pre-Development Information in this datasheet is based on product ideas in the planning phase of development. All specifications are design goals without any warranty and are subject to change without notice Pre-Production Information in this datasheet is based on products in the design, validation or qualification phase of development. The performance and parameters shown in this document are preliminary without any warranty and are subject to change without notice Production Information in this datasheet is based on products in ramp-up to full production or full production which conform to specifications in accordance with the terms of ams AG standard warranty as given in the General Terms of Trade Discontinued Information in this datasheet is based on products which conform to specifications in accordance with the terms of ams AG standard warranty as given in the General Terms of Trade, but these products have been superseded and should not be used for new designs ams Datasheet [v1-30] 2014-Sep-01 TCS3771 − Revision Information Revision Information Changes from 1-20 (2014-Aug-06) to current revision 1-30 (2014-Sep-01) The minimum Red Channel response to green light has been reduced from 8% to 6% Page(1) 8 Note(s) and/or Footnote(s): 1. Page numbers for the previous version may differ from page numbers in the current revision. ams Datasheet [v1-30] 2014-Sep-01 Page 47 Document Feedback TCS3771 − Content Guide Content Guide Page 48 Document Feedback 1 2 2 3 3 General Description Key Benefits & Features Applications End Products and Market Segments Block Diagram 4 5 6 7 12 13 Detailed Description Pin Assignments Absolute Maximum Ratings Electrical Characteristics Parameter Measurement Information Typical Characteristics 16 16 17 18 20 22 23 24 26 27 28 28 29 29 30 31 33 33 34 35 35 36 36 Principles of Operation System State Machine RGBC Operation Proximity Detection Interrupts State Diagram I2C Protocol Register Set Command Register Enable Register (0x00) RGBC Timing Register (0x01) Proximity Time Control Register (0x02) Wait Time Register (0x03) RGBC Interrupt Threshold Registers (0x04 − 0x07) Proximity Interrupt Threshold Registers (0x08 − 0x0B) Persistence Register (0x0C) Configuration Register (0x0D) Proximity Pulse Count Register (0x0E) Control Register (0x0F) ID Register (0x12) Status Register (0x13) RGBC Channel Data Registers (0x14 − 0x1B) Proximity Data Registers (0x1C − 0x1D) 37 37 38 Application Information LED Driver Pin with Proximity Detection PCB Pad Layout 39 Packaging Mechanical Data 41 42 Manufacturing Information Moisture Sensitivity 43 44 45 46 47 Ordering & Contact Information RoHS Compliant & ams Green Statement Copyrights & Disclaimer Document Status Revision Information ams Datasheet [v1-30] 2014-Sep-01