AAT2842INJ-EE-T1 Advanced Analog Technology, Inc., AAT2842INJ-EE-T1 Datasheet
AAT2842INJ-EE-T1
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AAT2842INJ-EE-T1 Summary of contents
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General Description The AAT2842 is a highly integrated charge pump with dual linear regulators optimized for systems operating with lithium-ion/polymer batteries. The charge pump provides power for both white LED backlight/keypad and flash four backlight LEDs can be ...
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Pin Descriptions Pin # Symbol Description 1 BL1 Backlight LED 1 current sink. BL1 controls the current through Backlight LED 1. Connect the cathode of Backlight LED 1 to BL1. If not used, connect BL1 to OUT. 2 BSET Backlight ...
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Pin Descriptions (continued) Pin # Symbol Description 24 FENS Flash enable and serial control input. FENS is the on/off control for the flash and the S input to serially control the flash LED brightness relative to the maximum current set ...
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Absolute Maximum Ratings Symbol Description IN, OUT, FL1, FL2, FL3, FL4, BL1, BL2, BL3, BL4 Voltage to AGND C1+, C1-, C2+, C2- Voltage to AGND BSET, FSET, CT, FBB, OUTA, FBA, OUTB, ENL, REF, FENS, BENS Voltage to AGND PGND ...
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Electrical Characteristics V = 3.6V 4.7µ 2.2µ OUT otherwise noted. Typical values are at T Symbol Description V IN Operating Voltage Range Operating Current IN( Shutdown Current IN(SHDN) ...
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Electrical Characteristics V = 3.6V 4.7µ 2.2µ OUT otherwise noted. Typical values are at T Symbol Description Enable/Set V , BENS(L) BENS, FENS Low Threshold V FENS( BENS(H) BENS, FENS High ...
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Typical Characteristics V = 3.6V 4.7µ 2.2µ OUT otherwise noted. Typical values are at T Backlight Efficiency vs. Supply Voltage 100 2.1mA/ch 7.5mA/ 2. ...
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Typical Characteristics V = 3.6V 4.7µ 2.2µ OUT otherwise noted. Typical values are at T BENS, FENS High Threshold Voltage vs. Supply Voltage 1.2 -40°C 1.1 1.0 0.9 0.8 25°C 0.7 85°C 0.6 ...
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Typical Characteristics V = 3.6V 4.7µ 2.2µ OUT otherwise noted. Typical values are at T LDOs A and B Load Regulation 1.00 0.50 0.00 -0.50 -1.00 0 Load Current (mA) LDOs ...
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Functional Block Diagram C1+ C1- C2+ C2- ENL BENS FENS CT BSET FSET Functional Description The AAT2842 is a highly integrated LED driver with two LDO linear regulators. The charge pump LED driver simultaneously drives the backlight and flash LEDs ...
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The backlight and flash LED currents are controlled by a combination of an external programming resistor from BSET (for backlight) or FSET (for flash) to AGND and the backlight or flash serial S 2 Cwire interface BENS or FENS. The ...
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Data FL Table 2: Flash Current Register: FL1-FL4 (R = 280kΩ). FSET Shutdown Since the sink switches are the only power returns ...
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R2 Standard 1% Values (R1 = 120K) V (V) OUT 2.8 2.5 2.0 1.8 1.5 Table 3: Example Output Voltages and Corresponding Resistor Values. Altering the Maximum LED Current Level from 30mA for Backlight and 150mA for Flash The value ...
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Using an additional resistor to connect the BSET pin with a digital output provides a LO/HI control. When the digital output is asserted high, the result- ing brightness level for the backlighting section is LO and the individual LED current ...
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Similarly, when the input falls further, such that 1.5X mode can no longer sustain LED drive cur- rent, the device will automatically switch to 2X mode mode, the output voltage can be boosted to twice the input voltage. ...
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Evaluation Board Layout Figure 2: AAT2842 Evaluation Board Top Layer. Evaluation Board User Interface The user interface for the AAT2842 evaluation board is provided through four buttons and a num- ber of connection terminals. The board is operated by supplying ...
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Button(s) Pushed 1 Description DATA Increment the data setting for the most recently activated mode. With backlight or movie mode activated, hold down the button to auto-cycle through the brightness levels. LIGHT Toggle ON/OFF the backlighting section. Set the brightness ...
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C11 0.1μF VIN DATA SW1 LIGHT SW2 MOVIE SW3 FLASH SW4 DC- Figure 5: MCU and I/O Expander Section Schematic. 18 High-Current Charge Pump with S Control and Dual LDO for Backlight and Flash ...
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... Evaluation Board Component Listing Component Part Number U1 AAT2842INJ-EE-T1, AAT2842IBJ-EE-T1 U2 PIC12F675 U3 AAT4291IJS-1- M673 D5, D6 LXCL-PWF1 C1, C2, C10 GRM18x C3, C5, C6, C7 GRM18x C4 GRM18x C8, C9, C11 GRM18x C12 TAJBx Chip Resistor R5 Chip Resistor Chip Resistor R9, R10 Chip Resistor R11 Chip Resistor ...
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... XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD. 20 High-Current Charge Pump with S Control and Dual LDO for Backlight and Flash 1 Part Number (Tape and Reel) AAT2842IBJ-EE-T1 AAT2842INJ-EE-T1 AAT2842 2 Cwire™ 2 Comments Not recommended for new designs Recommended for new designs ...
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Package Information 1 Pin 1 Dot by Marking 4.000 ± 0.050 Top View 0.750 ± 0.050 0.050 ± 0.050 Side View All dimensions in millimeters. 1. The leadless package family, which includes QFN, TQFN, DFN, TDFN and STDFN, has exposed ...
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N.B.: Not recommended for new designs. Index Area (D/2 x E/2) 4.00 ± 0.05 Top View 0.75 ± 0.05 0.05 ± 0.05 Side View All dimensions in millimeters. © Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of ...