AAT2846INJ-EE-T1 AnalogicTech, AAT2846INJ-EE-T1 Datasheet
AAT2846INJ-EE-T1
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AAT2846INJ-EE-T1 Summary of contents
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... The charge pump provides power for both white LED backlight and flash. Six backlight LEDs can be driv 30mA each, while up to two flash LEDs can be driven 600mA total. AnalogicTech Cwire™ (Advanced Simple Serial Control™) sin- ...
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Pin Descriptions Pin # Symbol Description 1 BL3 Backlight LED 3 current sink. BL3 controls the current through backlight LED 3. Connect the cathode of backlight LED 3 to BL3. If not used, connect BL3 to OUT. 2 BL2 Backlight ...
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Pin # Symbol Description 23 FEN Flash enable input. FEN is the on/off control for the flash LEDs. Drive FEN high to drive the maximum flash current, set by RFSET, through the flash LEDs. 24 FSET Flash current setting input. ...
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Absolute Maximum Ratings Symbol Description IN, OUT, FL1, FL2, BL1, BL2, BL3, BL4, BL5, BL6 Voltage to PGND FSET, CT, REF, FBB, OUTA, FBA, OUTB, ENA, ENB, FEN, ENS C1+, C1-, C2+, C2- Voltage to PGND PGND Voltage to AGND ...
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Electrical Characteristics V = 3.6V 4.7µ 2.2µ OUT noted. Typical values are T = 25°C. A Symbol Description V IN Operating Voltage Range Operating Current IN( Shutdown Current ...
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Electrical Characteristics V = 3.6V 4.7µ 2.2µ OUT noted. Typical values are T = 25°C. A Symbol Description ENS, FEN Logic Control (continued ENS(OFF) ENS, FEN Off Timeout t FEN(OFF) t ...
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Typical Characteristics Backlight Efficiency vs. Input Voltage 100 10.2mA/ch 1.6mA/ 2.7 3.1 3.5 3.9 4.3 Input Voltage (V) Backlight Current Matching vs. Temperature (20mA/ch; Data 21.0 20.5 20.0 19.5 19.0 18.5 -40 -15 ...
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Typical Characteristics Turn Mode Backlight (30mA/ch; Data (2V/div OUT (2V/div SINK (500mV/div (200mA/div) Time (200µs/div) BENS, FENS High Threshold Voltage vs. Input Voltage 1.4 1.3 ...
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Typical Characteristics LDOs A and B Turn On Characteristic V EN (2V/div OUT (500mV/div) 0V Time (50µs/div) LDOs A and B Load Regulation 1.0 0.5 0.0 -0.5 -1.0 0 Load Current (mA) LDOs A and B ...
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Typical Characteristics LDOs A and B Load Transient Response (10mA to 200mA Load Step OUT (100mA/div) V OUT (AC Coupled) (100mV/div) Time (50µs/div) 10 High Current Charge Pump with Dual LDO for Backlight and Flash Applications = 200mA ...
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Functional Block Diagram C1+ C1- 1x/1.5x/2x Charge Pump C2+ C2- ENA To LDO A ENB To LDO B ENS FEN CT FSET Functional Description The AAT2846 is a highly integrated backlight and flash LED driver with two LDO linear regulators. ...
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The backlight section has multiple current level scales and the maximum current level is fixed at 20mA or 30mA, depending on the scale chosen through programming. The flash section maximum current level is user programmable by an external set ...
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EN/SET Address Data Reg 1 Data Reg 2 Figure 1: AS Data 30mA Max (mA) 20mA Max (mA) 1 30.0 2 27.9 3 26.1 4 24.2 5 21.0 6 19.2 7 17.3 8 15.0 9 12.7 10 10.9 11 8.1 ...
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Flash Current FL1, FL2 (Address 4) The current level for the flash channels FL1 and FL2 is programmed by Address 4. Data 1 enables the maximum current level. The maximum current level is determined by the value of R and ...
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Backlight Independent Channel Control (Address 15) The AAT2846 has a unique independent channel control mode whereby individual backlight LED channels can be enabled and disabled to form a custom arrangement of active channels. To enable independent channel control mode, write ...
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R from FSET to AGND. Flash LED cur- FSET rent is set between 14% and 100% of the maximum current for both channels through Address 4. For lower current applications ...
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Applications Information LDO Output Voltage Programming The output voltages for LDOA and LDOB are pro- grammed by an external resistor divider network. As shown below, the selection of R1 and straight forward matter chosen by ...
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Selection of set resistor values outside of the typical application must be carefully evaluated to ensure that the application's performance requirements can still be met. Device Power Efficiency The AAT2846 power conversion efficiency depends on the charge pump mode. By ...
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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 compo- sition, and ambient temperature. Capacitor ...
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Evaluation Board Layout Figure 6: AAT2846 Evaluation Board Layout Top Side. Evaluation Board User Interface The user interface for the AAT2846 evaluation board is provided through 4 buttons and a number of connection terminals. The board is operated by supplying ...
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Button(s) Pushed 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 level ...
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C11 0.1μF VIN DATA SW1 LIGHT SW2 MOVIE SW3 FLASH SW4 DC- Figure 9: MCU and I/O Expander Section Schematic 22 High Current Charge Pump with Dual LDO for Backlight and Flash ...
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... Evaluation Board Component Listing Component Part# U1 AAT2846INJ-EE-T1 U2 PIC12F675 U3 AAT4290IJS-1-T1 D1-D6 LW M673 D7, D8 LXCL-PWF1 C1, C2 GRM18x C3-C7 GRM18x C4 GRM18x C8-C11 GRM18x C12 TAJBx R1-R4 Chip Resistor R5 Chip Resistor R6-R9 Chip Resistor R10 Chip Resistor R11 Chip Resistor R12, R14 Chip Resistor R13 Chip Resistor J1-J5 PRPN401PAEN LED7 ...
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... High Current Charge Pump with Dual LDO for Backlight and Flash Applications Marking 1 Part Number (Tape and Reel) UPXYY TQFN44-28-0.4 2.600 ± 0.050 Bottom View 0.400 ± 0.050 0.203 REF Pin 1 Indicator AAT2846 2 AAT2846INJ-EE-T1 Detail "A" C0.3 0.430 ± 0.050 Detail "A" 2846.2007.08.1.0 ...
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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’ ...