AAT2869 Advanced Analogic Technologies, Inc., AAT2869 Datasheet
AAT2869
Related parts for AAT2869
AAT2869 Summary of contents
Page 1
... LEDs, to enable/disable the LDOs, and to set the LDO's output. The programmable LED current ranges from 31mA to 0.4mA. Each output of the AAT2869 is equipped with built-in protection for short-circuit and auto-disable for load short-circuit conditions. The soft-start circuitry prevents excessive inrush current at charge pump start-up and mode transitions ...
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... LED driver current sink D4. Connect LED cathode to this pin. If not used, please tie to OUTCP. Charge pump enable/set. When in the low state, AAT2869 is powered down, and consumes less than 1μA. When EN/SET jumps from low to high, the charge pump is active and 20mA LED cur- ...
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... 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. Based on long-term current density limitation. 3. Mounted on an FR4 board. 2869.2010.01.1 PRODUCT DATASHEET AAT2869 Value Units -0.3 to 6.0 V -0 0.3 ...
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... Thermal Shutdown Hysteresis HYS J 1. The AAT2869 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assuredby 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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... LED = 5mA LED 0.06 0.04 0.02 0.00 -40 5.1 5.5 LDO Operating Current vs. Input Voltage 0.25 0.20 0.15 0.10 85°C 0.05 25°C -40°C 0.00 5.1 5.5 2 PRODUCT DATASHEET AAT2869 (1.5x Mode) 85°C 25°C -40°C 3.1 3.5 3.9 4.3 4.7 5.1 Input Voltage (V) Shutdown Current vs. Temperature 5. Temperature (° ° C) (LDOA Only) 85° ...
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... D2 0. 0.42 0.38 0.34 0. -40 LDO Load Regulation vs. Output Current 1.8 85°C 25°C 1.2 -40°C 0.6 0.0 -0.6 -1.2 -1.8 0.1 5.1 5 PRODUCT DATASHEET AAT2869 Frequency vs. Temperature - Temperature (° ° 3.6V 3.3V; 0.5mA/ch - Temperature (° 1.2V) OUT 85°C 25° ...
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... EN/SET Input Off Time vs. Input Voltage 360 300 240 180 85°C 25°C -40°C 120 5.1 5.5 2 PRODUCT DATASHEET AAT2869 EN Input Low Threshold Voltage vs. Input Voltage -40°C 25°C 85°C 3.1 3.5 3.9 4.3 4.7 5.1 Input Voltage (V) vs. Input Voltage -40°C 25° ...
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... Time (40μs/div) 8 (2V/div) (100mA/div) (2V/div) (20mA/div) (2V/div) (5V/div) (200mA/div) (20mA/div) = 2.2μF; LDOB (2V/div) (1A/div) (2V/div) (2V/div PRODUCT DATASHEET AAT2869 CP Turn Off (V = 3.6V 1μ 56nF; 31mA/ch OUT OUT ...
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... V LDOB (2V/div) (2V/div) (2V/div) (20mA/div 2.2μ 3.6V, V OUTB IN 100 PRODUCT DATASHEET AAT2869 LDO Turn Off (V = 3.6V 2.2μ 2.2μ LDOA LDOB V = 3.0V 1.8V) LDOA LDOB Time (1ms/div) ...
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... OUT I = 100mA 3.2 OUT I = 150mA OUT I = 200mA 3.0 OUT 2.8 2.6 2.4 3.1 3.2 2.7 (2V/div) V OUT (2V/div) I (20mA/div PRODUCT DATASHEET AAT2869 Dropout Characteristics (V = 3.0V) OUTA I = 0mA OUT I = 10mA OUT I = 50mA OUT I = 100mA OUT I = 150mA OUT I = 200mA OUT 2.8 2.9 3.0 3.1 Input Voltage (V) ...
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... LED current level. , and the pro- F The AAT2869 has five registers with up to four bits each to control LED backlighting enable/disable, LED current, enable/disable for the two LDOs, output voltages, etc. as shown in Table 1. Each data register can be written with EN/SET rising edges ...
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... Backlight LSBs BL[3] BL[ LDO[3] LDO[2] Table 1: AAT2869 AS Cwire Registers. 2 Address 1 – Backlight Fade Floor Settings When the fade-out function is enabled, the LED current decreases to the programmed floor level instead of decreasing to zero. The other bits of the register should be written with data 0. Addresses 2 and 3 – ...
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... Table 4: AS Cwire Register Addresses 2 and 3 2 2869.2010.01.1.0 Address 4 – LDO Enable Control LED Current The AAT2869 includes two low dropout (LDO) linear (mA) BL1 BL0 regulators. These regulators are powered from the bat- tery and produce a fixed output voltage which is set using ...
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... EN/SET pin to address and load the data registers. The timing diagram in Figure 1 shows the typical transmission protocol. The AAT2869 latches address or data after the EN/SET input has been held high for time t LAT AS Cwire interface. Address and data are differentiated by 2 the number of EN/SET rising edges ...
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... Figure 2: AAT2869 Total 32 LED Current Codes vs. LED Current. 2869.2010.01.1.0 Address LAT Figure 1: AS Cwire Timing Diagram. 2 address 3 registers after address 3 is written to determine which LED current code is programmed. The address 2 BL4 default value is 0 after one EN/SET rising edge ...
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... RC = 0.8 · C FADE-OUT F Charge Pump Efficiency 1x Mode Efficiency The AAT2869's 1x mode is operational at all times and functions alone to enhance device power conversion effi- ciency when V is higher than the voltage across the IN load. When in 1x mode, voltage conversion efficiency is defined as output power divided by input power. ...
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... Printed Circuit Board Layout Recommendations , When designing a PCB for the AAT2869, the key require- ments are: 1. Place the flying capacitors C1 and C2 as close to the chip as possible; otherwise 1.5x mode performance will be compromised. 2. Place the input and output decoupling capacitors as close to the chip as possible to reduce switching noise and output ripple ...
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... Schematic and Layout J1 DC+ DC- V _MCU R8 AAT2869 50k White LED Driver EN/SET R10 R11 R12 SELECT DETAIL SEND Figure 4: AAT2869 Evaluation Board Schematic. Figure 5: AAT2869 Evaluation Board Top Side Layout AAT2869 16 C2 C1+ C2- 1μ C1- OUTCP 7 IN ...
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... RS-0805UW LED1 0805KGCT LED2 0805KRCT CYCLE, UP, DOWN 6*6*5 Table 8: AAT2869IDT-DB1 Evaluation Board Bill of Materials. 2869.2010.01.1.0 Description Fade-in/Fade-out 4 Channel 1X/1.5X Charge Pump for White LEDs with Dual LDOs 8-Pin Flash-Based 8-Bit CMOS Microcontroller Res 0Ω 1/10W 1% 0603 SMD Res 49.9KΩ 1/10W 1% 0603 SMD Res 1KΩ ...
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... Marking 1 F3XYY TQFN3.0x2.2-18 3 0.20 ± 0.05 Pin 1 Indicator 0.40 BSC (optional) 0.30 ± 0.05 1.10 ± 0.05 Bottom View PRODUCT DATASHEET AAT2869 Part Number (Tape and Reel) 2 AAT2869IDT-T1 0.05 ± 0.05 Side View 2869.2010.01.1.0 ...