TSL2671 DIGITAL PROXIMITY DETECTOR r r TAOS118 - JANUARY 2011 Features PACKAGE FN DUAL FLAT NO-LEAD (TOP VIEW) D Proximity Detection with an Integrated LED Driver in a Single Device D Proximity Detection D D D D - Programmable Number of IR Pulses - Programmable Current Sink for the IR LED -- No Limiting Resistor Needed - Programmable Interrupt Function with Upper and Lower Threshold - Covers a 2000:1 Dynamic Range Programmable Wait Timer - Programmable from 2.72 ms to > 8 Seconds - Wait State -- 65 mA Typical Current I2C Interface Compatible - Up to 400 kHz (I2C Fast Mode) - Dedicated Interrupt Pin Small 2 mm 2 mm ODFN Package Sleep Mode -- 2.5 mA Typical Current VDD 1 6 SDA SCL 2 5 INT GND 3 4 LDR Package Image Not Actual Size Applications D D D D Cell Phone Touch Screen Disable Notebook/Monitor Security Automatic Speakerphone Enable Automatic Menu Popup Description The TSL2671 family of devices provides a complete proximity detection system and digital interface logic in a single 6-pin package. The device includes a digital proximity sensor with integrated LED driver for the required external IR LED. The proximity function offers a wide range of performance, with four programmable LED drive currents and a pulse repetition range of 1 to 32 pulses. The proximity detection circuitry compensates for ambient light, allowing it to operate in environments ranging from bright sunlight to dark rooms. This wide dynamic range also allows operation in short-distance detection applications behind dark glass, such as cell phones. An internal state machine provides the ability to put the device into a low-power mode for very low average power consumption. The proximity function specifically targets near-field proximity applications. In cell phones, for example, the proximity detection function can detect when the user positions the phone close to their ear. The device is fast enough to provide proximity information at the high repetition rate needed when answering a phone call. This provides both improved green power saving capability and the added security to lock the screen when the user may accidently deploy a touch. Communication with the device is accomplished through a simple two-wire I2C interface with data rates up to 400 kHz. An interrupt output pin is provided for connection to the host processor. This interrupt pin can be used to eliminate the need to poll the device on a repetitive basis. There is also a digital filter that compares the proximity ADC results to programmed values so that an interrupt is generated only upon a proximity event. The TSL2671 is supplied in a very small form factor 2-mm x 2-mm, 6-pin optical package, requiring very little PCB area. Also, the package height is only 0.65 mm high, which makes the TSL2671 suitable for very thin mechanical applications. The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r Texas Advanced Optoelectronic Solutions Inc. 1001 Klein Road S Suite 300 S Plano, TX 75074 S (972) r 673-0759 www.taosinc.com 1 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Functional Block Diagram Prox Integration Prox ADC INT I2C Interface Prox Control VDD Interrupt IR LED Constant Current Sink LDR Upper Limit Prox Data Lower Limit SCL SDA Wait Control GND CH0 CH1 Detailed Description The TSL2671 light-to-digital device provides on-chip photodiodes, integrating amplifiers, ADCs, accumulators, clocks, buffers, comparators, a state machine, and an I2C interface. Each device combines a Channel 0 photodiode (CH0), which is responsive to both visible and infrared light, and a channel 1 photodiode (CH1), which is responsive primarily to infrared light. Proximity detection can occur using either or both photodiodes. Two integrating ADCs simultaneously convert the amplified photodiode currents into 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. Proximity detection requires only a single external IR LED. An internal LED driver can be configured to provide a constant current sink of 12.5 mA, 25 mA, 50 mA, or 100 mA 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 16-s period. This LED current, coupled with the programmable number of pulses, provides a 2000:1 contiguous dynamic range. Communication to the device is accomplished through a fast (up to 400 kHz), two-wire I2C serial bus for easy connection to a microcontroller or embedded controller. The digital output of the device is inherently more immune to noise when compared to an analog interface. The device provides a separate pin for level-style interrupts. When interrupts are enabled and a pre-set 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 proximity value. An interrupt is generated when the value of a 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. Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 2 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Terminal Functions TERMINAL TYPE DESCRIPTION NAME NO. GND 3 INT 5 O Interrupt -- open drain. LDR 4 O LED driver for proximity emitter -- up to 100 mA, open drain. SCL 2 I I2C serial clock input terminal -- clock signal for I2C serial data. SDA 6 I/O VDD 1 Power supply ground. All voltages are referenced to GND. I2C serial data I/O terminal -- serial data I/O for I2C . Supply voltage. Available Options DEVICE ADDRESS PACKAGE - LEADS INTERFACE DESCRIPTION ORDERING NUMBER TSL26711 0x39 FN-6 I2C Vbus = VDD Interface TSL26711FN TSL26713 0x39 FN-6 I2C Vbus = 1.8 V Interface TSL26713FN TSL26715 0x29 FN-6 I2C Vbus = VDD Interface TSL26715FN FN-6 I2C TSL26717FN TSL26717 0x29 Vbus = 1.8 V Interface Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted) Supply voltage, VDD (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.8 V Digital output voltage range, VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5 V to 3.8 V Digital output current, IO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -1 mA to 20 mA Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40C to 85C ESD tolerance, human body model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2000 V Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTE 1: All voltages are with respect to GND. Recommended Operating Conditions MIN NOM MAX Supply voltage, VDD Supply voltage accuracy, VDD total error including transients 2.6 3 3.6 -3 3 % Operating free-air temperature, TA -30 70 C The LUMENOLOGY r Company UNIT V Copyright E 2011, TAOS Inc. r r www.taosinc.com 3 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Operating Characteristics, VDD = 3 V, TA = 25C (unless otherwise noted) PARAMETER TEST CONDITIONS MIN Active -- LDR pulse off IDD Supply current VOL INT SDA output low voltage INT, I LEAK Leakage current, SDA, SCL, INT pins I LEAK Leakage current, LDR pin VIH SCL SDA input high voltage SCL, VIL SCL SDA input low voltage SCL, TYP MAX 175 250 Wait mode 65 Sleep mode 2.5 A 4 3 mA sink current 0 0.4 6 mA sink current 0 0.6 -5 5 10 TSL26711, TSL26715 0.7 VDD TSL26713, TSL26717 1.25 UNIT V A A V TSL26711, TSL26715 0.3 VDD TSL26713, TSL26717 0.54 V Proximity Characteristics, VDD = 3 V, TA = 25C, PEN = 1 (unless otherwise noted) PARAMETER IDD TEST CONDITIONS Supply current LDR pulse on ADC conversion time step size PTIME = 0xFF CONDITION TYP 2.58 2.72 PTIME = 0xFF IR LED pulse count LED Drive mA 2.9 ms 256 steps 0 1023 counts 0 255 pulses Pulse -- LED on time PDRIVE=0 UNIT 1 Pulse period ISINK sink current @ 600 mV, LDR pin MAX 3 ADC number of integration steps ADC counts per step MIN 75 16.3 s 7.2 s 100 PDRIVE=1 50 PDRIVE=2 25 PDRIVE=3 12.5 Operating distance (See note 1) 125 mA 18 inches NOTE 1: 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 850 nm and a 20 half angle. The proximity surface used is 90% reflective (white surface) 16 x 20-inch Kodak Gray Card. 60 mw/SR, 100 mA, 64 pulses, open view (no glass). Note: Greater distances are achievable with appropriate system considerations. Wait Characteristics, VDD = 3 V, TA = 25C, WEN = 1 (unless otherwise noted) PARAMETER Wait step size TEST CONDITIONS CHANNEL WTIME = 0xFF Wait number of integration steps Copyright E 2011, TAOS Inc. TYP 2.58 2.72 1 MAX UNIT 2.9 ms 256 steps The LUMENOLOGY r Company r r 4 MIN www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 AC Electrical Characteristics, VDD = 3 V, TA = 25C (unless otherwise noted) PARAMETER (I2C TEST CONDITIONS MIN only) TYP 0 MAX UNIT 400 kHz f(SCL) Clock frequency t(BUF) Bus free time between start and stop condition 1.3 s t(HDSTA) Hold time after (repeated) start condition. After this period, the first clock is generated. 0.6 s t(SUSTA) Repeated start condition setup time 0.6 s t(SUSTO) Stop condition setup time 0.6 s t(HDDAT) Data hold time 0 s t(SUDAT) Data setup time 100 ns t(LOW) SCL clock low period 1.3 s t(HIGH) SCL clock high period 0.6 s tF Clock/data fall time 300 tR Clock/data rise time 300 ns Ci Input pin capacitance 10 pF ns Specified by design and characterization; not production tested. PARAMETER MEASUREMENT INFORMATION t(LOW) t(R) t(F) VIH SCL VIL t(HDSTA) t(BUF) t(HIGH) t(HDDAT) t(SUSTA) t(SUSTO) t(SUDAT) VIH SDA VIL P Stop Condition S S Start Condition Start P Stop t(LOWSEXT) SCLACK SCLACK t(LOWMEXT) t(LOWMEXT) t(LOWMEXT) SCL SDA Figure 1. Timing Diagrams The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 5 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 TYPICAL CHARACTERISTICS LDR OUTPUT COMPLIANCE SPECTRAL RESPONSIVITY 112.5 1 Ch 0 100 0.8 87.5 Load Current -- mA Normalized Responsivity 100 mA 0.6 0.4 Ch 1 75 62.5 50 mA 50 37.5 25 mA 25 0.2 12.5 mA 12.5 0 300 400 500 600 700 800 900 1000 1100 0 0 0.3 0.6 0.9 1.2 VOL - Output Low Voltage - V - Wavelength - nm Figure 2 Figure 3 NORMALIZED IDD vs. VDD and TEMPERATURE 110% 108% IDD Normalized @ 3 V, 25C 75C 106% 104% 50C 25C 102% 100% 0C 98% 96% 94% 92% 2.7 2.8 2.9 3 3.1 3.2 3.3 VDD -- V Figure 4 Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 6 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 PRINCIPLES OF OPERATION System State Machine The device provides control of proximity detection and power management functionality through an internal state machine. 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 cycle through the Proximity and Wait states. If these states are enabled, the device will execute each function. If the PON bit is set to a 0, the state machine will continue until the current conversion is complete and then go into a low-power sleep mode. Sleep PON = 1 (r0x00:b0) PON = 0 (r0x00:b0) Start Prox Wait Figure 5. Simplified State Diagram NOTE: 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 0x00, bit 0. This is represented as PON (r0x00:b0). The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 7 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 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 6). The amount of light detected from a reflected surface can then be used to determine an object's proximity to the sensor. Surface Reflectivity (SR) Glass Attenuation (GA) Distance (D) IR LED 2771 Background Energy (BGE) Optical Crosstalk (OC) Figure 6. Proximity Detection The device has controls for the number of IR pulses (PPCOUNT), the integration time (PTIME), the LED drive current (PDRIVE), and the photodiode configuration (PDIODE) (Figure 7). The photodiode configuration can be set to CH1 diode (recommended), CH0 diode, or a combination of both diodes. At the end of the integration cycle, the results are latched into the proximity data (PDATAx) registers. IR LED VDD PDRIVE(r0x0F, b7:6) PTIME(r0x02) IR LED Constant Current Sink Prox Control Prox Integration CH0 Prox ADC CH1 Prox Data PDATAH(r0x19), PDATAL(r0x18) PPCOUNT(r0x0E) Figure 7. Proximity Detection 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 12.5 mA, 25 mA, 50 mA, or 100 mA. For higher LED drive requirements, an external P type transistor can be used to control the LED current. Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 8 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 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 16-s period. Add IR + Background Subtract Background LED On LED Off 16 ms IR LED Pulses Figure 8. 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 2.72 ms. The combination of LED power and number of pulses can be used to control the distance at which the sensor can detect proximity. Figure 9 shows an example of the distances covered with settings such that each curve covers 2x the distance. Counts up to 64 pulses provide a 16x range. PROXIMITY ADC COUNT vs. RELATIVE DISTANCE 1000 25 mA, 1 Pulse 100 mA, 64 Pulses Proximity ADC Count 800 100 mA, 16 Pulses 600 400 100 mA, 4 Pulses 100 mA, 1 Pulse 200 0 1 2 4 8 16 Relative Distance Figure 9 The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 9 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Interrupts The interrupt feature simplifies and improves system efficiency by eliminating the need to poll the sensor for a proximity value. The interrupt mode is determined by the state of the PIEN field in the ENABLE register. Two 16-bit-wide interrupt threshold registers allow the user to define upper and lower threshold limits. An interrupt can be generated when the proximity data (PDATA) exceeds the upper threshold value (PIHTx) or falls below the lower threshold (PILTx). To further control when an interrupt occurs, the device provides an interrupt persistence feature. This feature allows the user to specify a number of conversion cycles for which an event exceeding the proximity interrupt threshold must persist (PPERS) before actually generating an interrupt. See the register descriptions for details on the length of the persistence. Prox Integration Prox ADC PIHTH(r0x0B), PIHTL(r0x0A) PPERS(r0x0C, b7:4) Upper Limit Prox Persistence Prox Data Lower Limit CH0 CH1 PILTH(r0x09), PILTL(r0x08) Figure 10. Programmable Interrupt Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 10 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 State Diagram The following state diagram 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 2.72-ms Start Delay will occur before entering the start state. If the PEN bit is set, the state machine will step through the proximity accumulate, then proximity ADC conversion states. As soon as the conversion is complete, the state machine will move to the Wait Check 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 12x over normal operation. When the wait counter terminates, the state machine will move to the 2.72-ms Wait Delay state before returning to the Start state. PON = 1 Start Delay PON = 0 Start 2.72 ms 1 to 255 LED Pulses Pulse Frequency: 62.5 kHz Time: 16.3 ms - 4.2 ms PEN = 1 Sleep 5.44 ms Prox Check Wait Delay PEN = 0 WEN = 0 Prox Accum Wait Check WEN = 1 1 to 256 steps Prox Step: 2.72 ms ADC Time: 2.72 ms - 696 ms Recommended - 2.72 ms 1023 Counts Wait WLONG = 0 1 to 256 steps Step: 2.72 ms Time: 2.72 ms - 696 ms WLONG = 1 1 to 256 steps Step: 32.6 ms Time: 32.6 ms - 8.35 s Figure 11. Expanded State Diagram The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 11 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Power Management Power consumption can be controlled through the use of the wait state timing because the wait state consumes only 65 A of power. Figure 14 shows an example of using the power management feature to achieve an average power consumption of 138 A current with four 100-mA pulses of proximity detection. 4 IR LED Pulses Prox Accum Prox ADC 65 ms (29 ms LED On Time) 2.72 ms Example: ~49 ms Cycle TIme Wait Wait Delay 43.52 ms 5.44 ms State Duration (ms) Current (mA) Prox Accum LED On Prox ADC Wait Wait Delay 0.065 (Note 1) 0.029 (Note 2) 2.72 43.52 5.44 100.0 0.175 0.065 0.175 Average Current = ((0.029 100) + (2.72 0.175) + (43.52 0.065) + (5.44 0.175)) / 52 = 138 mA Note 1: Prox Accum = 16.3 ms per pulse 4 pulses = 65 ms = 0.065 ms Note 2: LED On = 7.2 ms per pulse 4 pulses = 29 ms = 0.029 ms Figure 12. Power Consumption Calculations Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 12 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 I2C Protocol Interface and control are accomplished through an I2C 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 I2C addressing protocol. Devices TSL26711 and TSL26713 are at slave address 0x39, while the TSL26715 and TSL26717 devices are at slave address 0x29. The I2C standard provides for three types of bus transaction: read, write, and a combined protocol (Figure 13). 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 I2C bus protocol was developed by Philips (now NXP). For a complete description of the I2C protocol, please review the NXP I2C design specification at http://www.i2c-bus.org/references/. A N P R S S W ... Acknowledge (0) Not Acknowledged (1) Stop Condition Read (1) Start Condition Repeated Start Condition Write (0) Continuation of protocol Master-to-Slave Slave-to-Master 1 S 7 Slave Address 1 W 1 A 8 1 Command Code 8 A 1 Data Byte A 8 1 1 ... P I2C Write Protocol 1 S 7 Slave Address 1 R 1 A 8 1 Data A Data A 1 ... P I2C Read Protocol 1 7 1 1 8 1 1 8 1 1 S Slave Address W A Command Code A S Data R A 8 Data 1 8 A Data 1 1 A ... P I2C Read Protocol -- Combined Format Figure 13. I2C Protocols The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 13 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Register Set The device 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 Table 1. Table 1. Register Address ADDRESS RESISTER NAME R/W -- COMMAND W 0x00 ENABLE 0x02 0x03 0x08 0x09 0x0A REGISTER FUNCTION RESET VALUE Specifies register address 0x00 R/W Enables states and interrupts 0x00 PTIME R/W Proximity ADC time 0xFF WTIME R/W Wait time 0xFF PILTL R/W Proximity interrupt low threshold low byte 0x00 PILTH R/W Proximity interrupt low threshold high byte 0x00 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 filter 0x00 0x0D CONFIG R/W Configuration 0x00 0x0E PPCOUNT R/W Proximity pulse count 0x00 0x0F CONTROL R/W Control register 0x00 0x12 ID R Device ID 0x13 STATUS R Device status 0x00 0x18 PDATAL R Proximity ADC low data register 0x00 0x19 PDATAH R Proximity ADC high data register 0x00 ID The mechanics of accessing a specific register depends on the specific protocol used. See the section on I2C 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. Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 14 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Command Register The command registers specifies the address of the target register for future write and read operations. Table 2. Command Register 7 6 COMMAND COMMAND FIELD BITS COMMAND 7 TYPE 6:5 5 4 3 2 TYPE 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: FIELD VALUE DESCRIPTION 00 Repeated byte protocol transaction 01 Auto-increment protocol transaction 10 Reserved -- Do not use 11 Special function -- See description below Transaction type 00 will repeatedly read the same register with each data access. Transaction type 01 will provide an auto-increment function to read successive register bytes. ADD 4:0 Address register/special function register. 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: FIELD VALUE DESCRIPTION 00000 Normal -- no action 00101 Proximity interrupt clear Proximity Interrupt Clear clears any pending proximity interrupt. This special function is self clearing. Enable Register (0x00) The ENABLE register is used to power the device on/off, enable functions, and interrupts. Table 3. Enable Register 7 6 Reserved ENABLE 5 4 3 PIEN Resv Reserved WEN 2 1 PEN 0 PON Address 0x00 FIELD BITS DESCRIPTION Reserved 7:6 PIEN 5 Proximity interrupt mask. When asserted, permits proximity interrupts to be generated. Reserved 4 Reserved. Write as 0. 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 2:1 Proximity enable. These bits activate the proximity function. Writing a 11b enables proximity. Writing a 00b disables proximity. The Wait Time register should be configured before asserting proximity enable. PON 1, 2 0 Power ON. This bit activates the internal oscillator to permit the timers and ADC channel to operate. Writing a 1 activates the oscillator. Writing a 0 disables the oscillator. Reserved. Write as 0. NOTES: 1. See Power Management section for more information. 2. A minimum interval of 2.72 ms must pass after PON is asserted before proximity can be initiated. This required time is enforced by the hardware in cases where the firmware does not provide it. The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 15 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Proximity Time Control Register (0x02) The proximity timing register controls the integration time of the proximity ADC in 2.72 ms increments. It is recommended that this register be programmed to a value of 0xFF (1 integration cycle). Table 4. Proximity Time Control Register FIELD BITS PTIME 7:0 DESCRIPTION VALUE INTEG_CYCLES TIME MAX COUNT 0xFF 1 2.72 ms 1023 Wait Time Register (0x03) Wait time is set 2.72 ms increments unless the WLONG bit is asserted, in which case the wait times are 12x longer. WTIME is programmed as a 2's complement number. Table 5. Wait Time Register FIELD BITS WTIME 7:0 DESCRIPTION REGISTER VALUE WAIT TIME TIME (WLONG = 0) TIME (WLONG = 1) 0xFF 1 2.72 ms 0.032 sec 0xB6 74 201 ms 2.4 sec 0x00 256 696 ms 8.3 sec NOTE: The Wait Time register should be configured before PEN is asserted. 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. Table 6. Proximity Interrupt Threshold Registers REGISTER ADDRESS BITS PILTL 0x08 7:0 Proximity low threshold lower byte PILTH 0x09 7:0 Proximity low threshold upper byte PIHTL 0x0A 7:0 Proximity high threshold lower byte PIHTH 0x0B 7:0 Proximity high threshold upper byte Copyright E 2011, TAOS Inc. DESCRIPTION The LUMENOLOGY r Company r r 16 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 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 ADC integration cycle or if the ADC integration has produced a result that is outside of the values specified by threshold register for some specified amount of time. Table 7. Persistence Register 7 6 PERS 5 4 3 2 PPERS FIELD BITS PPERS 7:4 Reserved 1 0 Address 0x0C Reserved DESCRIPTION Proximity interrupt persistence. Controls rate of proximity interrupt to the host processor. 3:0 FIELD VALUE MEANING 0000 --- INTERRUPT PERSISTENCE FUNCTION 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 Default setting is 0x00. Configuration Register (0x0D) The configuration register sets the wait long time. Table 8. Configuration Register 7 6 5 CONFIG 4 3 2 Reserved 1 0 WLONG Reserved Address 0x0D FIELD BITS Reserved 7:2 DESCRIPTION WLONG 1 Wait Long. When asserted, the wait cycles are increased by a factor 12x from that programmed in the WTIME register. Reserved 0 Reserved. Write as 0. Reserved. Write as 0. The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 17 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 Proximity Pulse Count Register (0x0E) The proximity pulse count register sets the number of proximity pulses that will be transmitted. PPULSE defines the number of pulses to be transmitted at a 62.5-kHz rate. While the value can be programmed up to 255 pulses, the practical limit of the device is 32 pulses. It is recommended that 32 or fewer pulses be used to achieve maximum signal-to-noise ratio. Table 9. Proximity Pulse Count Register 7 6 5 4 PPULSE 3 2 1 0 Address 0x0E PPULSE FIELD BITS PPULSE 7:0 DESCRIPTION Proximity Pulse Count. Specifies the number of proximity pulses to be generated. Control Register (0x0F) The Control register provides four bits of control to the analog block. These bits control the diode drive current and diode selection functions. Table 10. Control Register 7 CONTROL 6 5 PDRIVE FIELD BITS PDRIVE 7:6 4 3 2 ResvPDIODE 5:4 3:0 Copyright E 2011, TAOS Inc. DESCRIPTION LED STRENGTH 00 100 mA 01 50 mA 10 25 mA 11 12.5 mA Proximity Diode Select. DIODE SELECTION 00 Reserved 01 Proximity uses the Channel 0 diode 10 Proximity uses the Channel 1 diode 11 Proximity uses both diodes Reserved. Write bits as 0. The LUMENOLOGY r Company r r 18 Address 0x0F LED Drive Strength. FIELD VALUE Reserved 0 Reserved FIELD VALUE PDIODE 1 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 ID Register (0x12) The ID Register provides the value for the part number. The ID register is a read-only register. Table 11. ID Register 7 6 5 4 ID 3 2 1 0 Address 0x12 ID FIELD BITS ID 7:0 DESCRIPTION 0x00 = TSL26711 and TSL26715 Part number identification 0x09 = TSL26713 and TSL26717 Status Register (0x13) The Status Register provides the internal status of the device. This register is read only. Table 12. Status Register 7 STATUS 6 Reserved FIELD BIT Reserved 7:6 PINT 5 Reserved 4:0 5 4 3 PINT Resv 2 1 Reserved 0 Address 0x13 DESCRIPTION Reserved. Proximity Interrupt. Indicates that the device is asserting a proximity interrupt. Reserved. Proximity Data Registers (0x18 - 0x19h) Proximity data is stored as a 16-bit value. To ensure the data is read correctly, a two-byte I2C read transaction should be utilized with auto increment protocol bits 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 the next ADC cycle ends between the reading of the lower and upper registers. Table 13. Proximity Data Registers REGISTER ADDRESS BITS PDATAL 0x18 7:0 Proximity data low byte PDATAH 0x19 7:0 Proximity data high byte The LUMENOLOGY r Company DESCRIPTION Copyright E 2011, TAOS Inc. r r www.taosinc.com 19 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 APPLICATION INFORMATION: HARDWARE LED Driver Pin with Proximity Detection The application hardware circuit with proximity detection requires an LED connected as shown in Figure 14. Vbat may be an independent power source. The 1-F decoupling capacitors should be of the low-ESR type and be placed as close as possible to the load and VDD to reduce noise. To maximize system performance, the use of PCB power and ground planes are recommended. If mounted on a flexible circuit, the power and ground traces back to the PCB should be sufficiently wide enough to have a low resistance, such as < 1. The I2C bus protocol was developed by Philips (now NXP). The pull-up resistor value (RP) is a function of the I2C bus speed, the supply voltage, and the capacitive bus loading. Users should consult the NXP I2C design specification (http://www.i2c-bus.org/references/) for assistance. With a lightly loaded bus running at 400 kbps and VDD = 3 V, 1.5-k resistors have been found to be viable. VBUS VDD(analog) VDD(digital) LED 1 mF RP RP 1 mF TSL2671 RPI LDR INT SCL SDA Figure 14. Application Hardware Circuit for Proximity Sensing with Internal LED Driver The power supply connection -- PCB routing and supply decoupling -- has a significant effect on proximity performance. Contact TAOS or see the application notes available at www.TAOSinc.com for power supply guidance. Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 20 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 APPLICATION INFORMATION: HARDWARE If the hardware application requires more than 100 mA of current to drive the LED, then an external transistor should be used. Note, R2 should be sized adequately to bias the gate voltage given the LDR current mode setting. See Figure 15. VBUS VDD(analog) VDD(digital) R2 1 mF RP RP 1 mF LED RPI R1 TSL2671 LDR INT SCL SDA Figure 15. Application Hardware Circuit for Proximity Sensing with External LED Driver Using P-FET Transistor PCB Pad Layout Suggested PCB pad layout guidelines for the Dual Flat No-Lead (FN) surface mount package are shown in Figure 16. 2500 Note: Pads can be extended further if hand soldering is needed. 1000 1000 400 650 1700 650 400 NOTES: A. All linear dimensions are in micrometers. B. This drawing is subject to change without notice. Figure 16. Suggested FN Package PCB Layout The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 21 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 MECHANICAL DATA PACKAGE FN Dual Flat No-Lead TOP VIEW Pin 1 Marker PIN OUT TOP VIEW PIN 1 2000 75 2000 75 VDD 1 6 SDA SCL 2 5 INT GND 3 4 LDR Photo-Active Area END VIEW SIDE VIEW 650 50 203 8 Seating Plane 650 300 50 BOTTOM VIEW 650 300 50 PIN 1 Pb 750 150 Lead Free NOTES: A. All linear dimensions are in micrometers. Dimension tolerance is 20 m unless otherwise noted. B. The photodiode active area is 466 m square and its center is 140 m above and 20 m to the right of the package center. The die placement tolerance is 75 m in any direction. C. Package top surface is molded with an electrically nonconductive clear plastic compound having an index of refraction of 1.55. D. Contact finish is copper alloy A194 with pre-plated NiPdAu lead finish. E. This package contains no lead (Pb). F. This drawing is subject to change without notice. Figure 17. Package FN -- Dual Flat No-Lead Packaging Configuration Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 22 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 MECHANICAL DATA TOP VIEW 2.00 0.05 1.75 4.00 1.50 4.00 B + 0.30 8.00 - 0.10 3.50 0.05 1.00 0.25 A B A DETAIL B DETAIL A 5 Max 5 Max 0.254 0.02 2.18 0.05 NOTES: A. B. C. D. E. F. G. 2.18 0.05 0.83 0.05 Ao Bo Ko All linear dimensions are in millimeters. Dimension tolerance is 0.10 mm unless otherwise noted. The dimensions on this drawing are for illustrative purposes only. Dimensions of an actual carrier may vary slightly. Symbols on drawing Ao, Bo, and Ko are defined in ANSI EIA Standard 481-B 2001. Each reel is 178 millimeters in diameter and contains 3500 parts. TAOS packaging tape and reel conform to the requirements of EIA Standard 481-B. In accordance with EIA standard, device pin 1 is located next to the sprocket holes in the tape. This drawing is subject to change without notice. Figure 18. Package FN Carrier Tape The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 23 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 MANUFACTURING INFORMATION The FN package has been tested and has demonstrated an ability to be reflow soldered to a PCB substrate. The process, equipment, and materials used in these test are detailed below. 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. Table 14. Solder Reflow Profile PARAMETER REFERENCE DEVICE Average temperature gradient in preheating Soak time 2.5C/sec tsoak 2 to 3 minutes Time above 217C (T1) t1 Max 60 sec Time above 230C (T2) t2 Max 50 sec Time above Tpeak -10C (T3) t3 Max 10 sec Peak temperature in reflow Tpeak 260C Temperature gradient in cooling Tpeak Max -5C/sec Not to scale -- for reference only T3 T2 Temperature (C) T1 Time (sec) t3 t2 tsoak t1 Figure 19. Solder Reflow Profile Graph Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 24 www.taosinc.com TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 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 Moisture Barrier Bags should be stored under the following conditions: Temperature Range Relative Humidity Total Time < 40C < 90% No longer than 12 months from the date code on the aluminized envelope if unopened. Rebaking of the reel will be required if the devices have been stored unopened for more than 12 months and the Humidity Indicator Card shows the parts to be out of the allowable moisture region. Opened reels should be used within 168 hours if exposed to the following conditions: Temperature Range Relative Humidity < 30C < 60% If rebaking is required, it should be done at 50C for 12 hours. The FN package has been assigned a moisture sensitivity level of MSL 3. The LUMENOLOGY r Company Copyright E 2011, TAOS Inc. r r www.taosinc.com 25 TSL2671 DIGITAL PROXIMITY DETECTOR TAOS118 - JANUARY 2011 PRODUCTION DATA -- information in this document is current at publication date. Products conform to specifications in accordance with the terms of Texas Advanced Optoelectronic Solutions, Inc. standard warranty. Production processing does not necessarily include testing of all parameters. LEAD-FREE (Pb-FREE) and GREEN STATEMENT Pb-Free (RoHS) TAOS' terms Lead-Free or Pb-Free mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TAOS Pb-Free products are suitable for use in specified lead-free processes. Green (RoHS & no Sb/Br) TAOS defines Green to mean Pb-Free (RoHS compatible), and 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 and Disclaimer The information provided in this statement represents TAOS' knowledge and belief as of the date that it is provided. TAOS 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. TAOS 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. TAOS and TAOS suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. NOTICE Texas Advanced Optoelectronic Solutions, Inc. (TAOS) reserves the right to make changes to the products contained in this document to improve performance or for any other purpose, or to discontinue them without notice. Customers are advised to contact TAOS to obtain the latest product information before placing orders or designing TAOS products into systems. TAOS assumes no responsibility for the use of any products or circuits described in this document or customer product design, conveys no license, either expressed or implied, under any patent or other right, and makes no representation that the circuits are free of patent infringement. TAOS further makes no claim as to the suitability of its products for any particular purpose, nor does TAOS assume any liability arising out of the use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS, INC. PRODUCTS ARE NOT DESIGNED OR INTENDED FOR USE IN CRITICAL APPLICATIONS IN WHICH THE FAILURE OR MALFUNCTION OF THE TAOS PRODUCT MAY RESULT IN PERSONAL INJURY OR DEATH. USE OF TAOS PRODUCTS IN LIFE SUPPORT SYSTEMS IS EXPRESSLY UNAUTHORIZED AND ANY SUCH USE BY A CUSTOMER IS COMPLETELY AT THE CUSTOMER'S RISK. LUMENOLOGY, TAOS, the TAOS logo, and Texas Advanced Optoelectronic Solutions are registered trademarks of Texas Advanced Optoelectronic Solutions Incorporated. Copyright E 2011, TAOS Inc. The LUMENOLOGY r Company r r 26 www.taosinc.com