AAT2845AIML-EE-T1 AnalogicTech, AAT2845AIML-EE-T1 Datasheet
AAT2845AIML-EE-T1
Related parts for AAT2845AIML-EE-T1
AAT2845AIML-EE-T1 Summary of contents
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... Each of the four channels is capable of driving up to 20mA per channel. AnalogicTech Cwire™ (Simple Serial Control™) serial digital input is used to enable, disable, and set current for each LED with 16 available settings down to 50µ ...
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Pin Descriptions Pin # Symbol Function 1 D2 Current sink input # Current sink input #1. 3 LDOB Output of LDO B. Connect a 2.2µF or larger ceramic capacitor to ground Input power supply for charge ...
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Absolute Maximum Ratings T = 25°C, unless otherwise noted. A Symbol Description IN, OUT, D1,D2, D3, D4 Voltage to GND C1+, C1-, C2+, C2- Voltage to GND LDOA, LDOB, FBA, FBB, EN/SET, ENLDO, CBP Voltage to GND PGND Voltage to ...
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Electrical Characteristics 2.2µ 25°C and V = 3.6V Symbol Description Power Supply V Supply Voltage IN Total Shutdown Current at VIN ...
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Electrical Characteristics 2.2µ 25°C and V = 3.6V Symbol Description LDOs I IN Operating Current IN V Feedback Voltage FB V ...
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Typical Characteristics 2.2µ 25°C and V = 3.6V Backlight Efficiency vs. Supply Voltage 100 1mA/ch 50 15.2mA/ch ...
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Typical Characteristics 2.2µ 25°C and V = 3.6V Backlight Operating Characteristic (V = 2.9V; 2X Mode; 13.5mA/ch Load ...
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Typical Characteristics 2.2µ 25°C and V = 3.6V EN/SET Low Threshold Voltage vs. Supply Voltage 1 0.9 -40°C 0.8 0.7 0.6 ...
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Typical Characteristics 2.2µ 25°C and V = 3.6V LDOs A and B Load Transient Response (V = 2.5V) OUT I OUT ...
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Functional Block Diagram IN EN/SET IN ENLDO CBP Functional Description The AAT2845A is an integrated solution for LCD display applications with a built-in driver for white LED backlight and two LDO voltage regulators for logic power supplies. The backlight driver ...
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... S 2 Cwire Serial Interface The current sink magnitude is controlled by AnalogicTech Cwire serial digital input. The interface records rising edges of the EN/SET pin and decodes them into 16 different states. The 16 current level settings available are indicated in Table 1 ...
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EN/SET 1 Data Reg Applications Information LED Selection The AAT2845A is specifically intended for driving white LEDs. However, the device design will allow the AAT2845A to drive most types of LEDs with for- ward voltage specifications ranging from 2.0V to ...
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To select appropriate resistor values, first choose R9 such that the feedback network bias current is reasonable. Then, according to the desired V calculate R8 according to the equation below. An example calculation follows chosen to be 120K, ...
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Charge Pump Mode Efficiency The AAT2845A contains a fractional charge pump which will boost the input supply voltage in the event where V is less than the voltage required to IN supply the output. The efficiency (η) ...
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Evaluation Board Layout Figure 3: AAT2845A Evaluation Board Top Layer. Evaluation Board User Interface The user interface for the AAT2845A evaluation board is provided by three buttons and two connec- tion terminals. The board is operated by supplying external power ...
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DC 100μF Optional 100μF capacitor to bypass lab supply OUTB C6 R10 2.2μF Programmed for 2.8V output 160K R11 120K 16 Four-Channel Backlight Driver with Dual LDOs VOUT ...
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... VIN DATA SW1 LIGHT SW2 ENLDO SW3 DC- Evaluation Board Component Listing Component Part# U1 AAT2845AIML-EE-T1 U2 PIC12F675 M673 GRM18x GRM18x C7 GRM18x C8 GRM31x C9 TAJBx Chip Resistor R4, R7 Chip Resistor R5 Chip Resistor R6 Chip Resistor R8 Chip Resistor R9, R11 Chip Resistor ...
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... Four-Channel Backlight Driver with Dual LDOs Marking 1 Part Number (Tape and Reel) YEXYY TQFN34-20 3.00 ± 0.05 1.55 ± 0.05 Top View Bottom View 7.5° ± 7.5° 0.021 ± 0.004 AAT2845A 2 AAT2845AIML-EE-T1 Detail "A" 0.425 ± 0.05 Detail "A" 2845A.2007.05.1.0 ...
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... 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 with- out notice. Except as provided in AnalogicTech’ ...