AAT3128ITO-T1

PRODUCT DATASHEET AAT3128 ChargePumpTM General Description The AAT3128 is a total solution controller for RGB LED fashion lighting. A simplified control scheme greatly reduces design complexity and accelerates time to market. The AAT3128 contains a high efficiency tri-mode charge pump DC/DC converter with 1X, 1.5X and 2X modes for color LED applications. Current source outputs drive two individual RGB LEDs for color displays, fashion and mood lighting. With a single-wire S2Cwire interface, an RGB LED module is easily controlled to display four distinct lighting mood effects. Low external parts count (two 1μF flying capacitors and two small bypass capacitors) and high conversion efficiency make the AAT3128 ideally suited for small battery-powered portable applications. The AAT3128 has a thermal management system to protect the device in the event of an output short circuit condition. Built-in soft-start circuitry prevents excessive inrush current during start-up. A low current shutdown feature disconnects the load from the input source and reduces quiescent current to less than 1μA. The AAT3128 is available in a 14-pin TSOPJW package. RGB LED Fashion Lighting Controller Features • • • • • • • • • • • 2.7V to 5.5V Input Voltage Range Compatible with Common Anode RGB LEDs Four S2Cwire Controlled Lighting Moods 0~60mA Programmable Current Source Low Noise Constant Frequency Operation No Inductors Small Application Circuit Regulated Output Current Integrated LED Control Switches Automatic Soft-Start Less than 1μA Shutdown Current Applications • • • • • • • Color Backlighting for Monochrome LCD Displays Color Display Lighting Fashion Lighting RGB LEDs Mobile Handsets MP3 Players PDAs Smart Phones Typical Application IN CP VBATTERY CIN 1μF COUT 1μF ISRC2 ISRC1 C1+ C1C2+ EN/SET RSET RSET 38.3kΩ GND C2DR DG DB AAT3128 C1 1μF R C1 1μF G B RGB LED 1 R G B RGB LED 2 EN/SET 3128.2008.02.1.1 www.analogictech.com 1 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM Pin Descriptions Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 RGB LED Fashion Lighting Controller Symbol RSET DG DR DB GND IN C2C2+ C1C1+ CP ISRC1 ISRC2 EN/SET Function Current Setting Resistor. Connect a resistor from RSET to GND to program the maximum LED current Green LED On/Off Switch. DG turns on/off the green LED. Connect the green LED cathode to DG. Red LED On/Off Switch. DR turns on/off the red LED. Connect the red LED cathode to DR. Blue LED On/Off Switch. DB turns on/off the blue LED. Connect the blue LED cathode to DB. Ground. Power Input. Connect the input power voltage source to IN. Connect a 1μF ceramic capacitor from IN to GND. Flying Capacitor 2 Negative Node. Connect a 1μF ceramic capacitor between C2+ and C2-. Flying Capacitor 2 Positive Node. Connect a 1μF ceramic capacitor between C2+ and C2-. Flying Capacitor 1 Negative Node. Connect a 1μF ceramic capacitor between C1+ and C1-. Flying Capacitor 1 Positive Node. Connect a 1μF ceramic capacitor between C1+ and C1-. Charge Pump Output. CP is the output voltage stage of the internal charge pump. Bypass CP to GND with a 1μF ceramic capacitor. LED Current Source 1. ISRC1 controls the current through the LEDs connected to it. Connect the RGB LED anode or LED array anodes to ISRC1. LED Current Source 2. ISRC2 controls the current through the LEDs connected to it. Connect the RGB LED anode or LED array anodes to ISRC2. Enable/Set Input. ENSET turns on/off the AAT3128 and is the S2Cwire serial interface input to control the LED color and brightness mood function. This node uses active high logic. Pin Configuration TSOPJW-14 (Top View) RSET DG DR DB GND IN C2- 1 2 3 4 5 6 7 14 13 12 11 10 9 8 EN/SET ISRC2 ISRC1 CP C1+ C1C2+ 2 www.analogictech.com 3128.2008.02.1.1 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM Absolute Maximum Ratings1 Symbol VIN, VCP VC1+, VC1-, VC2+, VC2VEN/SET, VRSET, VISRC1, VISRC2, VDG, VDR, VDB TJ TLEAD RGB LED Fashion Lighting Controller Description IN, CP to GND C1+, C1-, C2+, C2- to GND EN/SET, RSET, ISRC1, ISRC2, DG, DR, DB to GND Operating Junction Temperature Range Maximum Soldering Temperature (at leads, 10 sec) Value -0.3 to 6 -0.3 to VCP + 0.3 -0.3 to VIN + 0.3 -40 to 150 300 Units V V V °C °C Thermal Characteristics2 Symbol θJA PD Description Maximum Thermal Resistance Maximum Power Dissipation Value 160 625 Units °C/W mW 1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time. 2. Mounted on a FR4 board. 3128.2008.02.1.1 www.analogictech.com 3 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM Electrical Characteristics VIN = 3.6V, CIN = COUT = C1 = C2 = 1.0μF; TA = -40 to +85˚C. Unless otherwise noted, typical values are TA = 25˚C. Symbol Description Conditions Min 2.7 3.0 ≤ EN = 3.0 ≤ VIN = VIN ≤ 5.5, CP = 1.5x, No Load Current 0 VIN ≤ 5.5 3.5 3 -5 93 200 1 93 2 0.4 VEN/SET VEN/SET VEN/SET VEN/SET VEN/SET < > < > = 0.6V 1.4V 0.6V 1.4V 5V 1.4 0.3 50 500 500 1 75 RGB LED Fashion Lighting Controller Typ Max 5.5 7 10 5 Units V mA μA % % μs MHz % Ω V V μs ns μs μs μA Input Power Supply VIN Input Operation Range ICC Operating Current ISHDN Shutdown Current ISRC Output Current Accuracy η Efficiency Charge Pump Soft-Start Time TSS FCLK Clock Frequency η Efficiency Switches RDS(ON) Switch On Resistance EN/SET VEN(L) Enable Threshold Low VEN(H) Enable Threshold High TEN/SET LO EN/SET Low Time TEN/SET HI Minimum EN/SET High Time TOFF EN/SET Off Timeout TLAT EN/SET Latch Timeout IEN/SET EN/SET Input Leakage VIN = 3.5 VIN = 3.5, TA = 25°C -1 1. The AAT3128 is guaranteed to meet performance specification over the –40 to +85°C operating temperature range, and are assured by design, characterization and correlation with statistical process controls. 4 www.analogictech.com 3128.2008.02.1.1 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM Typical Characteristics Current Source Output vs. Input Voltage 90 6.0 RGB LED Fashion Lighting Controller Shutdown Current vs. Input Voltage ISRC1 Current (mA) 80 70 60 50 40 30 20 2.5 2.8 3.1 3.4 Shutdown Current (µA) -40°C 5.0 4.0 3.0 2.0 1.0 85°C 25°C 85°C 25°C -40°C 3.7 4.0 4.3 4.6 4.9 5.2 5.5 0.0 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5 Input Voltage (V) Input Voltage (V) Enable Input High Threshold vs. Input Voltage 1.2 1.1 1.0 1.2 Enable Input Low Threshold vs. Input Voltage 1.1 1.0 -40°C -40°C VIH (V) VIL (V) 25°C 85°C 0.9 0.8 0.7 0.6 0.5 0.4 2.7 3.0 3.3 3.6 3.9 4.2 4.5 4.8 5.1 5.4 0.9 0.8 0.7 0.6 0.5 0.4 2.7 3.0 3.3 3.6 3.9 4.2 4.5 4.8 5.1 5.4 25°C 85°C Input Voltage (V) Input Voltage (V) EN/SET Turn-Off Time vs. Input Voltage 400 350 300 S2Cwire Latch Enable Time vs. Input Voltage 400 350 -40°C TLAT (µs) -40°C 300 250 200 150 100 50 0 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5 TOFF (µs) 250 200 150 100 50 0 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5 25°C 85°C 25°C 85°C Input Voltage (V) Input Voltage (V) 3128.2008.02.1.1 www.analogictech.com 5 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM Typical Characteristics Input vs. Output Transient (VIN = 2.7V; Data 1) RGB LED Fashion Lighting Controller Input vs. Output Transient (VIN = 2.7V; Data 5) VISRC1 (2V/div) VIN (200mV/div) IIN (200mA/div) VISRC1 (2V/div) VIN (200mV/div) IIN (200mA/div) Time (500µs/div) Time (500µs/div) Input vs. Output Transient (VIN = 3.6V; Data 1) Input vs. Output Transient (VIN = 3.6V; Data 5) VISRC1 (2V/div) VIN (200mV/div) IIN (200mA/div) VISRC1 (2V/div) VIN (200mV/div) IIN (200mA/div) Time (500µs/div) Time (500µs/div) Input vs. Output Transient (VIN = 4.2V; Data 1) Input vs. Output Transient (VIN = 4.2V; Data 5) VISRC1 (2V/div) VIN (200mV/div) IIN (200mA/div) VISRC1 (2V/div) VIN (200mV/div) IIN (200mA/div) Time (500µs/div) Time (500µs/div) 6 www.analogictech.com 3128.2008.02.1.1 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM Functional Block Diagram RGB LED Fashion Lighting Controller Soft Start 1MHz Oscillator Voltage Reference RSET 1X 1.5X 2X Charge Pump C1+ C1C2+ C2CP ISRC1 Control ISRC2 Current Level Program and LED Switch / Mood DR DG DB EN/SET S Cwire Interface 2 Functional Description The AAT3128 is specifically designed to drive RGB color LEDs. This device is externally programmed via the simple single wire serial S2Cwire interface to set one of 16 color lighting modes based on four distinct preset color light mood schemes. In addition to the four color lighting moods, there are two brightness levels and two lightning sequence change speeds that may be selected. The AAT3128 utilizes a tri mode load switch (1X) and high efficiency (1.5X or 2X) charge pump boost converter intended for RGB color LED lighting applications. To maximize power conversion efficiency, an internal sensing circuit monitors the voltage required for the constant current source outputs and sets the load switch or charge pump modes based on the input battery voltage. As the battery discharges over time, the AAT3128 charge pump is enabled when the current source outputs near dropout. The charge pump initially starts in 1.5X mode. If the charge pump output droops enough for the current source output to become close to dropout, the charge pump will automatically transition to 2X mode. This load switch to charge pump control system provides the maximum power conversion efficiency for any given operating condition. The AAT3128 requires only four external components: two 1μF ceramic capacitors for the charge pump flying capacitors (C1 and C2), one 1μF ceramic input capacitor (CIN) and one 1μF ceramic output capacitor (CP). RGB LED Lighting Set-Up and Control The AAT3128 has four preset RGB LED color lighting moods which may be selected via the EN/SET function. These four lighting color moods are outlined in Table 1. Each lighting color mood mode selects a preset group of 64 unique colors that the system controller repeatedly sequences through at a selected fast or slow rate. RGB LED brightness and color change timing may be varied by a choice of two levels for both. The Brightness control permits the full current to power the RGB LED 3128.2008.02.1.1 www.analogictech.com 7 PRODUCT DATASHEET AAT3128 ChargePumpTM based on the current set level programmed by the RSET resistor. The second dimming level is fixed at 6dB below that programmed by the RSET resistor. The pace of the color change for a given mood light option can be set to a fast or slow rate. Through the S2Cwire interface, mood options allow the user to select between four different moods, each with two brightness levels and two speeds, based on the number of rising edges of the EN/SET pin. 16 unique moods are selected based on the settings in Table 2. RGB LED Fashion Lighting Controller timeout period. After the TOFF time out time, all internal registers are reset and the charge pump is disabled. It is advisable to issue a 500μs low pulse to reset the data registers before send new sets of data to change lighting modes. This will avoid any possibility of losing synchronization between the AAT3128 and the system MCU. Mood M1 M2 M3 M4 Name Rainbow 1 Electric Beat Rainbow 2 Firelight Color Description Full color wheel control with continuous smooth transitions Pulsing Blue – White – Red color tones Full color wheel control with varied timing for transitions Red-Orange-Yellow flickering light EN/SET Serial Interface The lighting mood output is controlled by the EN/SET pin, using AnalogicTech’s Simple Serial Control™ (S2Cwire) interface. The interface records rising edges of the EN/SET pin, and decodes them into 16 individual settings based on an internal preset ROM table. The interface counter can be clocked at speeds up to 1MHz. The rising edges of EN/SET input enable the IC and are counted for 1 to 16 edges based on the desired mode. Once the final clock cycle is input for the desired mode the EN/SET pin is held high to enable the device output. The device is disabled 500μs after the EN/SET pin transitions to a logic low state. The EN/SET timing is designed to accommodate a wide range of data rates. After the first rising edge of EN/SET, the charge pump is enabled and reaches full capacity after the soft-start time (TSS). During the soft start time, multiple clock pulses may be entered on the EN/SET pin to set the final output current level with a single burst of clocks. A constant current is sourced and the programmed color mood is enabled as long as EN/SET remains in a logic high state. The current source outputs are switched off after EN/SET has remained in a low state for at least the TOFF Table 1: Programmable RGB LED Color Lighting “Moods.” Data 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Bright/Dim B B B B B B B B D D D D D D D D Fast/Slow F F F F S S S S F F F F S S S S Mood M1 M2 M3 M4 M1 M2 M3 M4 M1 M2 M3 M4 M1 M2 M3 M4 Table 2: AAT3128 S2Cwire Programming Modes. EN/SET Timing tLO tHI tOFF EN/SET Code OFF 1 2 3 OFF Figure 1: S2Cwire Timing Diagram. 8 www.analogictech.com 3128.2008.02.1.1 PRODUCT DATASHEET AAT3128 ChargePumpTM Application Information RSET Selection The maximum output current for current sources ISRC1 and ISRC2 is programmed by the RSET resistor. A nominal value of 38.3kΩ will set each current source output to 60mA each. Lower maximum current levels may be programmed by reducing the value of RSET. Refer to Table 3 for RSET resistor values to set the maximum brightness constant current rounded off to the closest 1% value. Current Source Output (mA) 60 50 40 30 20 10 RGB LED Fashion Lighting Controller with the AAT3128. Since the ISRC1 and ISRC2 output current sources are matched with negligible voltage dependence, RGB LED brightness and color will be matched regardless of specific LED forward voltage (VF) variations. 0.08 Forward Current (IF) (A) 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0.00 1.00 1.50 2.00 2.50 3.00 3.50 4.00 RSET Value (kΩ) 38.3 46.6 57.6 76.8 115 232 Forward Voltage (VF ) (V) Figure 2: Typical RGB LED Forward Voltage vs. Forward Current Characteristics. Table 3: RSET Programming Values. If a desired current source output level is not listed in Table 3, the RSET resistor value may be calculated using the following formula: Capacitor Selection Careful selection of the four external capacitors CIN, C1, C2, and COUT is important because they will affect turnon time, output ripple, and transient performance. Optimum performance will be obtained when low equivalent series resistance (ESR) ceramic capacitors are used. In general, low ESR may be defined as less than 50mΩ. For best overall performance, 1μF capacitors are recommended. Depending on ripple requirements, the input and output capacitor values can be increased or decreased accordingly. If lower ripple is desired, increase the capacitor value. The peak-to-peak ripple seen at the input or output increases or decreases with capacitor size. RSET = Where: (1920 · VREF) IOUT VREF = 1.2V IOUT = Desired output current for ISRC1 and ISRC2 (ISRC1 = ISRC2 ≤ 60mA) RGB LED Selection The AAT3128 is specifically intended for driving RGB color LEDs. However, the device design will allow the AAT3128 to drive most types of LEDs with forward voltage specifications ranging from 1.0V to 5.0V. The two current sink outputs provide up to 60mA each and may be paralleled to drive high-current LEDs up to 120mA without complication. Most RGB color LEDs have greatly varied forward voltage specifications for each red, green and blue LED for a given forward current operating condition. Refer to Figure 2 or the datasheet for a given RGB LED to be used Capacitor Characteristics Ceramic composition capacitors are highly recommended over all other types of capacitors for use with the AAT3128. Ceramic capacitors offer many advantages over their tantalum and aluminum electrolytic counterparts. A ceramic capacitor typically has very low ESR, is lowest cost, has a smaller PCB footprint, and is nonpolarized. Low ESR ceramic capacitors help maximize charge pump transient response. Since ceramic capacitors are non-polarized, they are not prone to incorrect connection damage. 3128.2008.02.1.1 www.analogictech.com 9 PRODUCT DATASHEET AAT3128 ChargePumpTM Equivalent Series Resistance ESR is an important characteristic to consider when selecting a capacitor. ESR is a resistance internal to a capacitor that is caused by the leads, internal connections, size or area, material composition, and ambient temperature. Capacitor ESR is typically measured in milliohms for ceramic capacitors and can range to more than several ohms for tantalum or aluminum electrolytic capacitors. RGB LED Fashion Lighting Controller Capacitors that are physically larger will have a lower ESR when compared to a smaller case size capacitor made from an equivalent material. These larger devices can improve circuit transient response when compared to an equal value capacitor in a smaller package size. Layout Considerations The AAT3128 is a high-performance device that operates with a high switching frequency. To ensure optimal device performance and accommodate the fast switched capacitor transients generated by the AAT3128, special attention should be given to the printed circuit board (PCB) layout. The PCB traces connecting C1 and C2 experience fast current transients. As a result, the trace lengths for C1 and C2 should be minimized by placing the components as closely as possible to the IC. This will minimize path resistance and reduce ringing due to the inductance associated with trace length. For best IC performance, CIN and COUT are placed as closely as possible to the IN and CP pins and are connected to a solid ground. Ceramic Capacitor Materials Capacitors used in AAT3128 applications range in value from 0.47μF to 2.2μF. Nominally a 1μF capacitor with a minimum voltage specification exceeding 6V is recommended. Ceramic capacitors in this range are typically composed of X7R, X5R, Z5U, or Y5V dielectric materials. The use of X5R and X7R dielectric capacitors is strongly recommended due to their inherent low ESR characteristics and improved tolerance specifications over the device operating temperature range. AAT3128 Evaluation Board Layout Figure 3: AAT3128 Evaluation Board Component Side PCB Layout. Figure 4: AAT3128 Evaluation Board Solder Side PCB Layout. 10 www.analogictech.com 3128.2008.02.1.1 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM AAT3128 Evaluation Board Schematic RGB1 B G R B G RGB2 R RGB LED Fashion Lighting Controller JPx JPx R1 GND 38.3k 1 2 3 4 5 6 7 DC- DC+ 1 2 3 VIN JP1 C3 1μF RSET DG DR DB GND IN C2U1 EN/SET ISRC2 ISRC1 CP C1+ C1 C2+ AAT3128 14 13 12 11 10 9 8 C1 1μF C2 1μF C4 1μF GND J1 GND GND J2 R7 100K VIN GND R4 1k Cycle Up Down SW3 SW2 SW1 R3 1k R2 1k 1 2 3 4 VDD GP5 GP4 GP3 U2 VSS GP0 GP1 GP2 8 7 6 5 C5 1μF VR1 (opt) POT10K R5 1k LED2 RED PIC12F675 R6 1k LED1 GRN GND GND GND 3128.2008.02.1.1 www.analogictech.com 11 PRODUCT DATASHEET AAT3128 AAT3128 ChargePumpTM Ordering Information Package TSOPJW-14 RGB LED Fashion Lighting Controller Marking1 VMXYY Part Number (Tape and Reel)2 AAT3128ITO-T1 All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor products that are in compliance with current RoHS standards, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more information, please visit our website at http://www.analogictech.com/about/quality.aspx. Package Information TSOPJW-14 0.20 + 0.10 - 0.05 2.40 ± 0.10 0.40 BSC Top View 0.04 REF 3.05 + 0.05 - 0.10 + 0.000 1.00 - 0.075 2.85 ± 0.20 + 0.05 1.05 - 0.00 0.05 + 0.05 - 0.04 4° ± 4° 2.75 ± 0.25 0.15 ± 0.05 0.45 ± 0.15 Side View All dimensions in millimeters. 1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD. End View Advanced Analogic Technologies, Inc. 3230 Scott Boulevard, Santa Clara, CA 95054 Phone (408) 737-4600 Fax (408) 737-4611 © Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice. Except as provided in AnalogicTech’s terms and conditions of sale, AnalogicTech assumes no liability whatsoever, and AnalogicTech disclaims any express or implied warranty relating to the sale and/or use of AnalogicTech products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer’s applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders. 12 www.analogictech.com 3128.2008.02.1.1