View AAT3128ITO-T1_4131491.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

AAT3128
RGB LED Fashion Lighting Controller 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 1F 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 1A. The AAT3128 is available in a 14-pin TSOPJW package.
Features
* * * * * * * * * * *
ChargePumpTM
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 1A 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 1F COUT 1F ISRC2 ISRC1 C1+ C1C2+ EN/SET RSET RSET 38.3k GND C2DR DG DB
AAT3128
C1 1F R C1 1F G B RGB LED 1 R G B RGB LED 2
EN/SET
3128.2007.09.1.0
1
AAT3128
RGB LED Fashion Lighting Controller Pin Descriptions
Pin #
1 2 3 4 5 6 7 8 9 10 11 12 13 14
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 1F ceramic capacitor from IN to GND. Flying Capacitor 2 Negative Node. Connect a 1F ceramic capacitor between C2+ and C2-. Flying Capacitor 2 Positive Node. Connect a 1F ceramic capacitor between C2+ and C2-. Flying Capacitor 1 Negative Node. Connect a 1F ceramic capacitor between C1+ and C1-. Flying Capacitor 1 Positive Node. Connect a 1F 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 1F 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 C2EN/SET ISRC2 ISRC1 CP C1+ C1C2+
1 2 3 4 5 6 7
14 13 12 11 10 9 8
2
3128.2007.09.1.0
AAT3128
RGB LED Fashion Lighting Controller Absolute Maximum Ratings1
Symbol
VIN, VCP VC1+, VC1-, VC2+, VC2VEN/SET, VRSET, VISRC1, VISRC2, VDG, VDR, VDB TJ TLEAD
Description
IN, CP to GND C1+, C1-, C2+, C2- to GND
Value
-0.3 to 6 -0.3 to VCP + 0.3 -0.3 to VIN + 0.3 -40 to 150 300
Units
V V
EN/SET, RSET, ISRC1, ISRC2, DG, DR, DB to GND Operating Junction Temperature Range Maximum Soldering Temperature (at leads, 10 sec)
V C C
Thermal Characteristics
Symbol
JA PD
Description
Maximum Thermal Resistance Maximum Power Dissipation2
2
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. 3128.2007.09.1.0
3
AAT3128
RGB LED Fashion Lighting Controller Electrical Characteristics
VIN = 3.6V, CIN = COUT = C1 = C2 = 1.0F; TA = -40 to +85C. Unless otherwise noted, typical values are TA = 25C Symbol Description Conditions Min
2.7 3.0 VIN 5.5, CP = 1.5x, No Load Current EN = 0 3.0 VIN 5.5 VIN = 3.5 3
Typ
Max
5.5 7 10 5
Units
V mA A % % s MHz %
Input Power Supply VIN Input Operation Range ICC ISHDN ISRC Charge Pump TSS FCLK Switches RDS(ON) EN/SET VEN(L) VEN(H) TEN/SET LO TEN/SET HI TOFF TLAT IEN/SET Operating Current Shutdown Current Output Current Accuracy Efficiency Soft-Start Time Clock Frequency Efficiency Switch On Resistance Enable Threshold Low Enable Threshold High EN/SET Low Time Minimum EN/SET High Time EN/SET Off Timeout EN/SET Latch Timeout EN/SET Input Leakage
-5 93 200 1 93 2
VIN = 3.5 VIN = 3.5, TA = 25C
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
-1
V V s ns s s A
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
3128.2007.09.1.0
AAT3128
RGB LED Fashion Lighting Controller Typical Characteristics
Current Source Output vs. Input Voltage
90 6.0
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 (A)
-40C
5.0 4.0 3.0 2.0 1.0
85C
25C
85C
25C
-40C
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
-40C
-40C
VIH (V)
VIL (V) 25C 85C
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
25C
85C
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
-40C
-40C TLAT (s)
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 (s)
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
25C
85C
25C
85C
Input Voltage (V)
Input Voltage (V)
3128.2007.09.1.0
5
AAT3128
RGB LED Fashion Lighting Controller Typical Characteristics
Input vs. Output Transient
(VIN = 2.7V; Data 1)
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 (500s/div)
Time (500s/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 (500s/div)
Time (500s/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 (500s/div)
Time (500s/div)
6
3128.2007.09.1.0
AAT3128
RGB LED Fashion Lighting Controller Functional Block Diagram
IN
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
S2Cwire Interface
GND
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
3128.2007.09.1.0
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 1F ceramic capacitors for the charge pump flying capacitors (C1 and C2), one 1F ceramic input capacitor (CIN) and one 1F 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 7
AAT3128
RGB LED Fashion Lighting Controller
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 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. set 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 500s 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 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 500s 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.
EN/SET Serial Interface
The lighting mood output is controlled by the EN/SET pin, using AnalogicTech's Simple Serial ControlTM (S2Cwire) interface. The interface records rising edges of the EN/SET pin, and decodes them into 16 individual settings based on an internal pre-
Mood
M1
Name
Rainbow 1
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
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
M2
Electric Beat
M3
Rainbow 2
M4
Firelight
Table 1: Programmable RGB LED Color Lighting "Moods."
Table 2: AAT3128 S2Cwire Programming Modes.
8
3128.2007.09.1.0
AAT3128
RGB LED Fashion Lighting Controller
EN/SET Timing
tHI tLO
tOFF
EN/SET Code
OFF
1
2
3
OFF
Figure 1: S2Cwire Timing Diagram.
Application Information
RSET Selection
The maximum output current for current sources ISRC1 and ISRC2 is programmed by the RSET resistor. A nominal value of 38.3k 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 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 highcurrent 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 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
RSET Value (k)
38.3 46.6 57.6 76.8 115 232
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
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: RSET = Where: VREF = 1.2V IOUT = Desired output current for ISRC1 and ISRC2 (ISRC1 = ISRC2 60mA) (1920 * VREF) IOUT
Forward Voltage (VF ) (V)
Figure 2: Typical RGB LED Forward Voltage vs. Forward Current Characteristics.
3128.2007.09.1.0
9
AAT3128
RGB LED Fashion Lighting Controller
Capacitor Selection
Careful selection of the four external capacitors CIN, C1, C2, and COUT is important because they will affect turn-on 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 50m. For best overall performance, 1F 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.
Ceramic Capacitor Materials
Capacitors used in AAT3128 applications range in value from 0.47F to 2.2F. Nominally a 1F 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. 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.
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 non-polarized. Low ESR ceramic capacitors help maximize charge pump transient response. Since ceramic capacitors are non-polarized, they are not prone to incorrect connection damage.
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.
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.
10
3128.2007.09.1.0
AAT3128
RGB LED Fashion Lighting Controller AAT3128 Evaluation Board Layout
Figure 3: AAT3128 Evaluation Board Component Side PCB Layout.
Figure 4: AAT3128 Evaluation Board Solder Side PCB Layout.
3128.2007.09.1.0
11
AAT3128
RGB LED Fashion Lighting Controller Ordering Information
Package
TSOPJW-14
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/pbfree.
Package Information
TSOPJW-14
2.40 0.10 0.40 BSC
Top View
2.85 0.20
7 NOM 3.05 + 0.05 - 0.10
0.9625 0.0375
0.04 REF
+ 0.10 1.00 - 0.065
0.055 0.045
4 4 2.75 0.25
0.15 0.05
0.45 0.15
Side View
All dimensions in millimeters.
End View
1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD.
12
3128.2007.09.1.0
AAT3128
RGB LED Fashion Lighting Controller
(c) 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.
Advanced Analogic Technologies, Inc.
3230 Scott Boulevard, Santa Clara, CA 95054 Phone (408) 737-4600 Fax (408) 737-4611
3128.2007.09.1.0
13

▲Up To Search▲

Price & Availability of AAT3128ITO-T1

	To Download AAT3128ITO-T1 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .