lp5526tlx National Semiconductor Corporation, lp5526tlx Datasheet

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... The device is controlled through 2-wire low voltage I compatible interface that reduces the number of required connections. Typical Application © 2006 National Semiconductor Corporation Features n High efficiency boost converter with programmable output voltage up to 20V n 2 individual drivers for serial display backlight LEDs ...

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Typical Application (Continued) Connection Diagrams Top View www.national.com 25-Bump Thin Micro SMD Package, Large Bump NS Package Number TLA25CCA 20179771 2 20179701 20179772 Bottom View ...

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... IRT Input Package Mark Ordering Information Order Number LP5526TL LP5526TLX Boost Converter Power Switch Boost Converter Feedback Red LED Output (Current Sink / Open Drain Switch) Green LED Output (Current Sink / Open Drain Switch) Blue LED Output (Current Sink / Open Drain Switch) ...

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Absolute Maximum Ratings 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. V (SW, FB, MAIN, SUB, RLED, GLED, BLED DD1 DD2 DDIO ...

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Electrical Characteristics Limits in standard typeface are for < < (- +85 C). Unless otherwise noted, specifications apply to the LP5526 Block Diagram with 100nF, C ...

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Block Diagram www.national.com 6 20179774 ...

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Modes of Operation RESET: In the RESET mode all the internal registers are reset to the default values. Reset is entered always if input NRST is LOW or internal Power On Reset is active. Power On Reset (POR) will activate ...

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Power-Up Sequence When powering up the device, V DD1 greater than V to prevent any damage to the device. DDIO Magnetic Boost DC/DC Converter The LP5526 Boost DC/DC Converter generates an 8…20V supply voltage for the LEDs from single Li-Ion ...

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Magnetic Boost DC/DC Converter MAGNETIC BOOST DC/DC CONVERTER ELECTRICAL CHARACTERISTICS Symbol Parameter I Maximum Non-Continuous LOAD Load Current I Maximum Continuous Load LOAD Current V Output Voltage Accuracy OUT (FB Pin) RDS Switch ON Resistance ON f PWM Mode Switching ...

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Boost Converter Typical Performance Characteristics Vin = 3.6V, Vout = 20.0V if not otherwise stated Boost Converter Efficiency Battery Current vs Voltage Boost Line Regulation 3.0V - 3.6V, no load www.national.com Boost Typical Waveforms at 150mA Load 20179779 Boost Output ...

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Boost Converter Typical Performance Characteristics Boost Load Transient Response 50mA – 150mA Boost Maximum Current vs. Output Voltage Autoload Effect on Input Current, No Load 20179785 20179795 11 (Continued) 20179786 www.national.com ...

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Functionality of Color LED Outputs (RLED, GLED, BLED) LP5526 has one RGB/color LED output, consisting of three individual LED output pins. Output pins can be used in switch mode or constant current mode. Output mode can be selected with the ...

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Functionality of Color LED Outputs (RLED, GLED, BLED) Overlapping Mode In overlapping mode the brightness is controlled using PWM duty cycle based control method as the following figure shows. Since RGB outputs are on simuneltaneously, the maximum load peak current ...

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Functionality of Color LED Outputs (RLED, GLED, BLED) (Continued) Switch Mode / Constant Current Mode Each RGB LED output can be set to act as a switch or a constant current sink. Selection of mode is done with the CC_SW ...

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Functionality of Color LED Outputs (RLED, GLED, BLED) (Continued) FLASH LED DRIVING USING RGB DRIVERS RGB drivers can be connected in parallel and used as a flash LED driver (see Typical application 2). Flash LEDs can be powered through the ...

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Functionality of Color LED Outputs (RLED, GLED, BLED) Controlling RGB Max Current Values to Introduce Flash www.national.com (Continued) 16 20179703 ...

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Functionality of Color LED Outputs (RLED, GLED, BLED) (Continued) When RLED, GLED and BLED are connected together as in Typical Application 1, flash current can be adjusted with 8.33% step in constant current mode by changing RGB max current register ...

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Functionality of Color LED Outputs (RLED, GLED, BLED) (Continued) FLASH SAFETY TIMER FUNCTION Flash safety function can be used to prevent damages due to possible overheating when flash or RGB LEDs have been stuck on because of software or user ...

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Backlight Drivers LP5526 has 2 independent backlight drivers. Both drivers are regulated constant current sinks. LED current for both LED strings are controlled by the 8-bit current mode DACs with 0.1 mA step. MAIN and SUB LEDs can be also ...

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Backlight Drivers (Continued) FADE IN / FADE OUT LP5526 has an automatic fade in and out for main and sub backlight. The fade function is enabled with EN_FADE bit. The slope of the fade curve is set by the SLOPE ...

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Backlight Driver Electrical Characteristics Symbol Parameter I Maximum Sink Current MAX I Leakage Current LEAKAGE I MAIN Current tolerance MAIN I SUB Current tolerance SUB Match Sink Current Matching Error MAIN-SUB Match Sink Current Matching Error MAIN-SUB V 95% Saturation ...

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General Purpose I/O Functionality LP5526 has three general purpose I/O pins: GPIO[0]/PWM, GPIO[1] and GPIO[2]. GPIO[0]/PWM can also be used as a PWM input for the external LED PWM controlling. GPIO bi-directional drivers are operating from the V domain. Registers ...

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I C Compatible Interface SIGNALS 2 The SCL pin is used for the I C clock and the SDA pin is used for bidirectional data transfer. Both these signals need 2 a pull-up resistor according to ...

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I C Compatible Interface w = write (SDA = “0” read (SDA = “1”) ack = acknowledge (SDA pulled down by either master or slave repeated start id = 7-bit chip address, 59H (101 1001b) ...

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I C Compatible Interface TIMING PARAMETERS (V = 3.0 to 4.5V, V DD1,2 Symbol 1 Hold Time (repeated) START Condition 2 Clock Low Time 3 Clock High Time 4 Setup Time for a Repeated START Condition ...

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Recommended External Components OUTPUT CAPACITOR, C OUT The output capacitor C directly affects the magnitude of OUT the output ripple voltage. In general, the higher the value the lower the output ripple magnitude. Multilayer ce- OUT ramic ...

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LP5526 Register Bit Explanations Each register is shown with a key indicating the accessibility of the each individual bit, and the initial condition: CONTROL REGISTER (00H) – RGB LEDS CONTROL REGISTER D7 D6 RGB_PWM EN_RGB ...

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LP5526 Register Bit Explanations RGB MAX CURRENT (02H) – MAXIMUM RGB CURRENT CONTROL REGISTER D7 D6 SAFETY_SET SAFETY_SET IR[1:0] IG[1:0] IB[1:0] IR,IG,IB[1:0] WLED CONTROL (03H) – WLED CONTROL REGISTER SLOPE R ...

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LP5526 Register Bit Explanations MAIN CURRENT (04H) – MAIN CURRENT CONTROL REGISTER SUB CURRENT (05H) – SUB CURRENT CONTROL REGISTER GPIO CONTROL (06H) – ...

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LP5526 Register Bit Explanations ENABLES (0BH) – ENABLES REGISTER NSTBY EN_BOOST NSTBY EN_BOOST EN_FLASH EN_AUTOLOAD BOOST OUTPUT (0DH) – BOOST OUTPUT VOLTAGE CONTROL REGISTER ...

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LP5526 Register Bit Explanations PWM ENABLE (2BH) – EXTERNAL PWM CONTROL REGISTER D7 D6 EN_SAFETY_R EN_SAFETY_G EN_SAFETY_R EN_SAFETY_G EN_SAFETY_B EN_EXT_R_PWM EN_EXT_G_PWM EN_EXT_B_PWM EN_EXT_MAIN_PWM EN_EXT_SUB_PWM www.national.com (Continued EN_EXT EN_EXT EN_SAFETY_B R_PWM G_PWM ...

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Physical Dimensions inches (millimeters) unless otherwise noted The dimension for X1 ,X2 and X3 are as given: • X1=2.543mm ± 0.03mm • X2=2.543mm ± 0.03mm • X3=0.60mm ± 0.075mm 25-bump micro SMD Package, 2.54 x 2.54 x 0.6mm, 0.5mm pitch ...