ADP1650ACBZ-R7

1.5 A LED Flash Driver with I2C-Compatible Interface ADP1650 FEATURES APPLICATIONS Camera-enabled cellular phones and smart phones Digital still cameras, camcorders, and PDAs FUNCTIONAL BLOCK DIAGRAM INPUT VOLTAGE = 2.7V TO 5.0V 10µF 1.0µH TX1/TORCH VIN GPIO1 SW VOUT TX2/ILED/ADC GPIO2 10µF ADP1650 STROBE LED_OUT MAX 1.5A SCL SGND PGND 08837-001 SDA EN Figure 1. Li-ION + C1 L1 PGND Li-ION + C2 INDUCTOR DIGITAL INPUT/ OUTPUT AREA = 16.4mm 2 LED ANODE 08837-002 Ultracompact solution Small, 2 mm × 1.5 mm, 12-ball WLCSP package Thin, 3 mm × 3 mm × 0.75 mm, 10-lead LFCSP package Smallest footprint, 1 mm height, 1 μH power inductor LED current source for local LED grounding Simplified routing to/from LED Improved LED thermals Synchronous 3 MHz PWM boost converter, no external diode High efficiency: 90% peak Reduces high levels of input battery current during flash Limits battery current drain in torch mode I2C programmable Currents up to 1500 mA in flash mode for 1 LED with ±7% accuracy over all conditions Currents up to 200 mA in torch mode Programmable dc battery current limit (4 settings) Programmable flash timer up to 1600 ms Low VBAT mode to reduce LED current automatically 4-bit ADC for LED VF, die/LED temperature readback Control I2C-compatible control registers External STROBE and torch input pins 2 transmitter mask (TxMASK) inputs Safety Thermal overload protection Inductor fault detection LED short-/open-circuit protection Figure 2. PCB Layout (WLCSP) GENERAL DESCRIPTION The ADP1650 is a very compact, highly efficient, single white LED flash driver for high resolution camera phones that improves picture and video quality in low light environments. The device integrates a programmable 1.5 MHz or 3 MHz synchronous inductive boost converter, an I2C-compatible interface, and a 1500 mA current source. The high switching frequency enables the use of a tiny, 1 mm high, low cost, 1 μH power inductor, and the current source permits LED cathode grounding for thermally enhanced, low EMI, and compact layouts. The LED driver maximizes efficiency over the entire battery voltage range to maximize the input-power-to-LED-power conversion and to minimize battery current draw during flash events. A programmable dc battery current limit safely maximizes LED current for all LED VF and battery voltage conditions. Two independent TxMASK inputs permit the flash LED current and battery current to reduce quickly during a power amplifier current burst. The I2C-compatible interface enables the programmability of timers, currents, and status bit readback for operation monitoring and safety control. The ADP1650 is available in a compact 12-ball, 0.5 mm pitch WLCSP package and a 10-lead LFCSP package, and operates within specification over the full −40°C to +125°C junction temperature range. Rev. C Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2010–2011 Analog Devices, Inc. All rights reserved. ADP1650 TABLE OF CONTENTS Features .............................................................................................. 1  Indicator LED Driver................................................................. 14  Applications....................................................................................... 1  Low Battery LED Current Foldback ........................................ 14  Functional Block Diagram .............................................................. 1  Programmable Battery DC Current Limit.............................. 15  General Description ......................................................................... 1  Analog-to-Digital Converter Operation ................................. 15  Revision History ............................................................................... 2  5 V Output Operation ............................................................... 16  Specifications..................................................................................... 3  Safety Features................................................................................. 18  Recommended Specifications: Input and Output Capacitance and Inductance ............................................................................. 5  Short-Circuit Fault ..................................................................... 18  I2C-Compatible Interface Timing Specifications ..................... 5  Dynamic Overvoltage Mode (DOVP) .................................... 18  Absolute Maximum Ratings............................................................ 6  Timeout Fault.............................................................................. 18  Thermal Data ................................................................................ 6  Overtemperature Fault .............................................................. 18  Thermal Resistance ...................................................................... 6  Indicator LED Fault ................................................................... 18  ESD Caution.................................................................................. 6  Current Limit.............................................................................. 18  Pin Configurations and Function Descriptions ........................... 7  Input Undervoltage .................................................................... 18  Typical Performance Characteristics ............................................. 8  Soft Start ...................................................................................... 18  Theory of Operation ...................................................................... 12  Reset Using the Enable (EN) Pin ............................................. 18  White LED Driver ...................................................................... 12  Clearing Faults ............................................................................ 18  Modes of Operation ................................................................... 12  I2C Interface ................................................................................ 19  Assist Light .................................................................................. 13  I2C Register Map............................................................................. 20  Flash Mode .................................................................................. 13  Applications Information .............................................................. 26  Assist-to-Flash Operation ......................................................... 13  External Component Selection ................................................ 26  Torch Mode ................................................................................. 13  PCB Layout...................................................................................... 28  Torch-to-Flash Mode ................................................................. 14  Outline Dimensions ....................................................................... 29  TxMASK Operation................................................................... 14  Ordering Guide .......................................................................... 29  Overvoltage Fault ....................................................................... 18  Frequency Foldback ................................................................... 14  REVISION HISTORY 4/11—Rev. B to Rev. C Added 10-Lead LFCSP Package........................................Universal Changes to Features Section, General Description Section, and Figure 2 Caption ............................................................................... 1 Changes to Table 1............................................................................ 3 Changes to Table 5............................................................................ 6 Added Figure 5; Renumbered Sequentially .................................. 7 Changes to Table 6............................................................................ 7 Changes to PCB Layout Section and Figure 45 Caption........... 28 Added Figure 46.............................................................................. 28 Updated Outline Dimensions ....................................................... 29 Changes to Ordering Guide .......................................................... 29 Changed GND to Power Ground Throughout .............................6 Changed IL to IL, ILED to ILED, LED OUT to LED_OUT, and IBAT to IBAT Throughout ..................................................................8 Change to Figure 10 Caption ...........................................................8 Change to Figure 11 Caption ...........................................................9 Changed LED_MOD = 10 to LED_MOD = 11 in Figure 32 ... 14 Changes to Analog-to-Digital Converter Operation Section and Figure 37 .......................................................................................... 15 Changes to Selecting the Output Capacitor Section.................. 26 2/11—Rev. A to Rev. B Changes to Features Section and General Description Section . 1 Changes to Switching Regulator, Voltage Output Mode, VOUT Voltage Parameter and Digital Inputs/GPIO, Torch Glitch Filtering Delay Parameter, Table 1.................................................. 3 5/10—Revision 0: Initial Version 6/10—Rev. 0 to Rev. A Changes to Contact Information.....................................................1 Rev. C | Page 2 of 32 ADP1650 SPECIFICATIONS VIN 1 = 3.6 V, TJ = −40°C to +125°C for minimum/maximum specifications, and TA = 25°C for typical specifications, unless otherwise noted. Table 1. Parameter 2 SUPPLY Input Voltage Range Undervoltage Lockout Threshold Undervoltage Lockout Hysteresis Shutdown Current (IQ), EN = 0 V Standby Current (ISTBY), EN = 1.8 V Operating Quiescent Current SW Switch Leakage LED DRIVER LED Current Assist Light, Torch Flash LED Current Error—WLCSP LED Current Error—LFCSP LED Current Source Headroom—WLCSP LED Current Source Headroom—LFCSP LED_OUT Ramp-Up Time LED_OUT Ramp-Down Time SWITCHING REGULATOR Switching Frequency Minimum Duty Cycle nFET Resistance—WLCSP pFET Resistance—WLCSP nFET Resistance—LFCSP pFET Resistance—LFCSP Voltage Output Mode VOUT Voltage—WLCSP VOUT Voltage—LFCSP Output Current Line Regulation Load Regulation Conditions Min VIN falling 2.7 2.3 50 TJ = −40°C to +85°C, current into VIN pin, VIN = 2.7 V to 4.5 V TJ = −40°C to +85°C, current into VIN pin, VIN = 2.7 V to 4.5 V Torch mode, LED current = 100 mA TJ = −40°C to +85°C, VSW 3 = 4.5 V TJ = 25°C, VSW 3 = 4.5 V Assist light value setting = 0 (000 binary) Assist light value setting = 7 (111 binary) Flash value setting = 0 (00000 binary) Flash value setting = 24 (11000 binary) ILED = 700 mA to 1100 mA ILED = 300 mA to 650 mA, 1150 mA to 1500 mA ILED = 75 mA to 200 mA ILED = 25 mA to 50 mA ILED = 700 mA to 1100 mA ILED = 300 mA to 650 mA, 1150 mA to 1500 mA ILED = 75 mA to 200 mA ILED = 25 mA to 50 mA Flash, 1200 mA LED current Torch, 200 mA LED current Flash, 1200 mA LED current Torch, 200 mA LED current Typ 2.4 100 0.2 3 5.3 Max Unit 5.0 2.5 150 1 10 V V mV μA μA mA μA μA 2 0.5 25 200 300 1500 −6 −7 −10 −15 −6 −7 −10 −15 +6 +7 +10 +15 +6 +7 +10 +18 290 190 370 220 0.6 0.1 Switching frequency = 3 MHz Switching frequency = 1.5 MHz Switching frequency = 3 MHz Switching frequency = 1.5 MHz ILOAD at VOUT = 300 mA Rev. C | Page 3 of 32 mA mA mA mA % % % % % % % % mV mV mV mV ms ms 2.8 1.4 3 1.5 14 7 60 50 77 85 3.2 1.6 MHz MHz % % mΩ mΩ mΩ mΩ 4.575 4.575 5.000 5.000 5.425 5.500 500 V V mA %/V %/A 0.3 −0.7 ADP1650 Parameter 2 Pass-Through Mode Transition, Flash VIN to LED_OUT, Entry VIN to LED_OUT, Exit Pass-Through Mode Transition, Torch VIN to LED_OUT, Entry VIN to LED_OUT, Exit DIGITAL INPUTS/GPIO Input Logic Low Voltage Input Logic High Voltage GPIO1, GPIO2, STROBE Pull-Down Torch Glitch Filtering Delay INDICATOR LED LED Current Accuracy Short-Circuit Detection Threshold Open-Circuit Detection Threshold ADC Resolution Error Input Voltage Range, GPIO2 SAFETY FEATURES Maximum Timeout For Flash Timer Accuracy DC Current Limit Low VBAT Mode Transition Voltage Error Hysteresis Coil Peak Current Limit Conditions Min Typ Max Unit 1200 mA LED current 1200 mA LED current 580 435 mV mV 200 mA LED current 200 mA LED current 380 285 mV mV 0.54 1.26 From torch rising edge to device start 5.5 390 7 −22 7.5 +22 1.2 2.45 4 External voltage mode VF mode, TJ = 25°C VF mode, TJ = −40°C to +125°C External voltage mode 0 0 DC current value setting = 0 (00 binary) DC current value setting = 1 (01 binary) DC current value setting = 2 (10 binary) DC current value setting = 3 (11 binary) −7.0 1.35 1.55 1.8 2.02 Bits LSB LSB LSB V +7.0 1.65 1.95 2.2 2.5 ms % A A A A 3.2 Peak current value setting = 0 (00 binary) Peak current value setting = 1 (01 binary) Peak current value setting = 2 (10 binary) Peak current value setting = 3 (11 binary) Overvoltage Detection Threshold LED_OUT Short-Circuit Detection Comparator Reference Voltage Thermal Shutdown Threshold TJ Rising TJ Falling 1.55 2.02 2.47 2.7 5.15 50 1.75 2.25 2.75 3.0 5.5 1.2 150 140 1 VIN is the input voltage to the circuit. All limits at temperature extremes are guaranteed via correlation using standard statistical quality control (SQC). 3 VSW is the voltage on the SW switch pin. 2 Rev. C | Page 4 of 32 % V V ±1 ±1 ±1.5 0. 5 1600 1.5 1.75 2.0 2.25 V V kΩ ms 1.95 2.5 3.0 3.3 5.9 1.3 % mV A A A A V V °C °C ADP1650 RECOMMENDED SPECIFICATIONS: INPUT AND OUTPUT CAPACITANCE AND INDUCTANCE Table 2. Parameter CAPACITANCE Input Output MINIMUM AND MAXIMUM INDUCTANCE Symbol CMIN L Conditions Min Typ Max Unit TA = −40°C to +125°C TA = −40°C to +125°C TA = −40°C to +125°C 4.0 3.0 0.6 10 10 1.0 20 1.5 μF μF μH I2C-COMPATIBLE INTERFACE TIMING SPECIFICATIONS Table 3. Parameter 1 fSCL tHIGH tLOW tSU, DAT tHD, DAT tSU, STA tHD, STA tBUF tSU, STO tR tF tSP CB 2 2 Max 400 0.6 1.3 100 0 0.6 0.6 1.3 0.6 20 + 0.1 CB 2 20 + 0.1 CB2 0 Unit kHz μs μs ns μs μs μs μs μs ns ns ns pF 0.9 300 300 50 400 Description SCL clock frequency SCL high time SCL low time Data setup time Data hold time Setup time for repeated start Hold time for start/repeated start Bus free time between a stop and a start condition Setup time for stop condition Rise time of SCL and SDA Fall time of SCL and SDA Pulse width of suppressed spike Capacitive load for each bus line Guaranteed by design. CB is the total capacitance of one bus line in picofarads. SDA tLOW tR tF tSU, DAT tF tHD, STA tSP tBUF tR SCL S tHD, DAT tHIGH tSU, STA Sr S = START CONDITION Sr = REPEATED START CONDITION P = STOP CONDITION tSU, STO P S 08837-003 1 Min Figure 3. I2C-Compatible Interface Timing Diagram Rev. C | Page 5 of 32 ADP1650 ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE Table 4. Parameter VIN, SDA, SCL, EN, GPIO1, GPIO2, STROBE, LED_OUT, SW, VOUT to Power Ground PGND to SGND Ambient Temperature Range (TA) Junction Temperature Range (TJ) Storage Temperature ESD Human Body Model ESD Charged Device Model ESD Machine Model Rating −0.3 V to +6 V −0.3 V to +0.3 V −40°C to +85°C −40°C to +125°C JEDEC J-STD-020 ±2000 V ±500 V ±150 V Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. θJA of the package is based on modeling and calculation using a 4-layer board. θJA is highly dependent on the application and board layout. In applications where high maximum power dissipation exists, attention to thermal board design is required. The value of θJA may vary, depending on PCB material, layout, and environmental conditions. The specified value of θJA is based on a 4-layer, 4 in × 3 in, 2 ½ oz copper board, per JEDEC standards. For more information, see the AN-617 Application Note, MicroCSP™ Wafer Level Chip Scale Package. θJA is specified for a device mounted on a JEDEC 2S2P PCB. Table 5. Thermal Resistance Package Type 12-Ball WLCSP 10-Lead LFCSP ESD CAUTION THERMAL DATA The ADP1650 may be damaged if the junction temperature limits are exceeded. Monitoring TA does not guarantee that TJ is within the specified temperature limits. In applications with high power dissipation and poor thermal resistance, the maximum TA may have to be derated. In applications with moderate power dissipation and low PCB thermal resistance, the maximum TA can exceed the maximum limit as long as the TJ is within specification limits. TJ of the device is dependent on the TA, the power dissipation (PD) of the device, and the junction-to-ambient thermal resistance (θJA) of the package. Maximum TJ is calculated from the TA and PD using the following formula: TJ = TA + (PD × θJA) Rev. C | Page 6 of 32 θJA 75 42.5 Unit °C/W °C/W ADP1650 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS BALL A1 INDICATOR 1 2 3 PGND SGND VIN SW GPIO2 GPIO1 VOUT STROBE EN A B VIN 1 GPIO2 2 GPIO1 3 LED_OUT SDA SDA 4 SCL SCL 5 D ADP1650 TOP VIEW 9 EN 8 SW 7 VOUT 6 LED_OUT NOTES 1. THE EXPOSED PADDLE MUST BE CONNECTED TO GROUND. 08837-004 TOP VIEW (BALL SIDE DOWN) Not to Scale 10 STROBE Figure 4. WLCSP Pin Configuration 08837-070 C Figure 5. LFCSP Pin Configuration Table 6. Pin Function Descriptions WLCSP A1 A2 A3 B1 B2 Pin No. LFCSP N/A 1 N/A1 1 8 2 Mnemonic PGND SGND VIN SW GPIO2 B3 3 GPIO1 C1 7 VOUT C2 10 STROBE C3 9 EN D1 D2 D3 6 4 5 0 LED_OUT SDA SCL EPAD 1 Description Power Ground. Signal Ground. Input Voltage for the Device. Connect an input bypass capacitor close to this pin. Boost Switch. Connect the power inductor between SW and the input capacitor. ILED/TX2/ADC. Mode is register selectable. Red indicator LED current source or TxMASK2 or ADC input. ILED Mode. Connect to red LED anode. Connect the LED cathode to power ground. TxMASK2 Mode. Reduces the current to the programmable TxMASK2 current. ADC Mode. This pin is used as the input pin for the ADC. Torch/TX1. Mode is register selectable. External torch mode or TxMASK1 input. Torch Mode. Enables the integrated circuit (IC) in direct torch mode. TxMASK1 Mode. Reduces the flash current to the programmable TxMASK1 current. Boost Output. Connect an output bypass capacitor very close to this pin. This is the output for the 5 V external voltage mode. Strobe Signal Input. This pin synchronizes the flash pulse to the image capture. In most cases, this signal comes directly from the image sensor. Enable. Set EN low to bring the quiescent current (IQ) to