AAT2803 AAT, AAT2803 Datasheet
AAT2803
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AAT2803 Summary of contents
Page 1
... General Description The AAT2803 is a dual charge pump designed to sup- port both white LED backlight and flash applications for systems operating with lithium-ion/polymer batter- ies. The backlight charge pump is capable of driving up to six LEDs at a total of 180mA. The current sinks may be operated in group or in parallel for driving higher current LEDs ...
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... This pin should not be left floating. EP Exposed paddle (bottom); connect to GND directly beneath package. Pin Configuration 2 Six-Channel White LED Backlight QFN44-24 (Top View VOUT_FL AAT2803 VIN GND 4 15 EN_FL VIN 5 14 N/C GND 6 13 Charge Pump with Flash . When con- IN 2803.2006.04.1.5 ...
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Absolute Maximum Ratings Symbol Description V Input Voltage IN V EN/SET to GND Voltage EN/SET T Operating Junction Temperature Range J T Maximum Soldering Temperature (at leads, 10 sec) LEAD Thermal Information 2 Symbol Description P Maximum Power Dissipation D ...
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... V Enable Threshold High EN(H) 1. The AAT2803 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls. 2. Determined by the average of all active channels. 3. Current matching is defined as the deviation of any sink current from the average of all active channels. ...
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... OFF T EN/SET Latch Timeout LAT I Input Leakage EN/SET;EN_FL 1. The AAT2803 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls. 2803.2006.04.1.5 Six-Channel White LED Backlight 1.0μ -40°C to +85°C, unless otherwise noted. ...
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Typical Characteristics–Flash Driver Charge Pump Section Output Voltage vs. Output Current (V = 4.5V; EN_FL = V ; EN/SET = GND) OUT_FL IN 4.60 4.56 3.6V 4.52 4.48 3.0V 3.3V 4.44 2.7V 4.40 0.1 1.0 10.0 Output Current (mA) Start-Up ...
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Typical Characteristics–Flash Driver Charge Pump Section Output Ripple Voltage vs. Time (I = 50mA @ V = 3.5V) OUT (10mV/div) V OUT (10mV/div (10mA/div) 500ns/div Supply Current vs. Supply Voltage 3. 0μA OUT ...
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Typical Characteristics–White LED Backlight Driver Section Unless otherwise noted 3.6V Efficiency vs. Supply Voltage 100 4.1mA 10.2mA 2.8 3.0 3.2 3.4 3.6 Supply ...
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Typical Characteristics–White LED Backlight Driver Section Unless otherwise noted 3.6V Load Characteristics (V = 3.8V; 1.5X Mode; 15mA Load (40mV/div) CP (40mV/div) V SINK (40mV/div) 500ns/div Load Characteristics (V = 4.0V; 1.5X Mode; ...
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Typical Characteristics–White LED Backlight Driver Section Unless otherwise noted 3.6V vs. V LAT IN 350 300 -40°C 250 200 150 25°C 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 ...
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... AS Cwire EN/SET Interface Functional Description The AAT2803 is a dual charge pump targeted for backlight and flash applications. The charge pump for white LED applications is a tri-mode load switch (1X) and high efficiency (1.5X or 2X) charge pump device. To maximize power conversion efficiency, an internal sensing circuit monitors the voltage ...
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Constant Current Output Level Settings The constant current sink levels for the white LED backlight (D1 to D6) are set via the serial interface according to a logarithmic scale where each code is 1dB lower than the previous code. In ...
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AS Cwire Serial Interface Timing 2 EN/SET Address Data Reg 1 Data Reg 2 AS Cwire Addressing 2 Five addresses are available to enable all of the part's functionality. Two 4-bit registers control the main and sub-channels, giving 16 settings ...
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... In some instances (e.g., in high-luminous-output 0 applications such as photo flash), it may be neces- 0 sary to drive high-V 0 current sinks in the AAT2803 make it capable of 0.05 driving LEDs with forward voltages as high as 4.7V 0.5 at full current from an input supply as low as 3.0V. Outputs can be paralleled to drive high-current 1 LEDs without complication. ...
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... Capacitor Characteristics Ceramic composition capacitors are highly recom- mended over all other types of capacitors for use with the AAT2803. Ceramic capacitors offer many advantages over their tantalum and aluminum elec- trolytic counterparts. A ceramic capacitor typically has very low ESR, is lowest cost, has a smaller PCB footprint, and is non-polarized ...
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... Phone (408) 737-4600 Fax (408) 737-4611 16 Six-Channel White LED Backlight Marking Part Number (Tape and Reel) 1 OFXYY QFN44-24 0.305 ± 0.075 R0.030Max 2.7 ± 0.05 Bottom View 0.214 ± 0.036 Side View Charge Pump with Flash 2 AAT2803ISK-4.5-T1 Pin 1 Identification 1 6 2803.2006.04.1.5 ...