MAX8790AETP+T Maxim Integrated Products, MAX8790AETP+T Datasheet
MAX8790AETP+T
Specifications of MAX8790AETP+T
Related parts for MAX8790AETP+T
MAX8790AETP+T Summary of contents
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... Thin QFN MAX8790AETP+ -40°C to +85°C (4mm x 4mm) + Denotes a lead-free package. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. o Drives Six Parallel Strings with Multiple Series- Connected LEDs per String o ± ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications ABSOLUTE MAXIMUM RATINGS IN, SHDN, to GND .................................................-0.3V to +28V FB_ to GND ............................................................-0.3V to +28V V , BRT, ENA, OSC GND ...........................-0.3V to +6V CC ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 12V SHDN IN PARAMETER INPUT LEAKAGE Leakage Current CS Leakage Current V CS OSC Leakage Current ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications ELECTRICAL CHARACTERISTICS (Circuit of Figure 12V SHDN IN PARAMETER Input Voltage Range BRT = GND IN ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 12V SHDN IN PARAMETER LED CURRENT ISET = V Full-Scale FB_ Output Current R ISET R ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications (Circuit configuration 12V, V SHDN IN BOOST CONVERTER EFFICIENCY vs. INPUT VOLTAGE (BRT = 100 500kHz 92 750kHz 1MHz 88 ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications (Circuit configuration 12V, V SHDN IN SWITCHING WAVEFORMS (BRT = 15%, ANALOG DIMMING) MAX8790A toc10 V LX 10V/div 500mA/div 0mA 1μs/div LED ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications (Circuit configuration 12V, V SHDN IN LED-SHORT FAULT PROTECTION (BRT = 100%, 2 LEDs SHORT ON FB3) 10ms/div PIN NAME O sci l l ator ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications PIN NAME LED String 6 Cathode Connection. FB6 is the open-drain output of an internal regulator, which controls 11 FB6 current through FB6. FB6 can sink up to ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications Detailed Description The MAX8790A is a high-efficiency driver for arrays of white LEDs. It contains a fixed-frequency, current- mode, PWM step-up controller, 5V linear regulator, dim- ming control ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications IN 5V LINEAR REGULATOR OSCILLATOR TRI-LEVEL OSC COMPARATOR SHDN CCV REF ADJ ISET CLK OSC FSET 256 x f BRT V - 0.4V CC ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications Fixed-Frequency Step-Up Controller The MAX8790A’s fixed-frequency, current-mode, step- up controller automatically chooses the lowest active FB_ voltage to regulate the feedback voltage. Specifically, the difference between the lowest ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications At startup, the MAX8790A checks each FB_ pin to determine if the respective current string is enabled. Each FB_ pin is internally pulled up with a 180µA cur- ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications Open-Current Source Protection The MAX8790A step-up converter output voltage is reg- ulated according to the minimum value of the enable FB_ voltages individual LED string is ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications In digital dimming mode, the step-up controller and current source are directly turned on and off by the PWM signal. The current pulse magnitude, or full-scale current, is ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications The PLL is disabled in DPWM mode; consequently, the BRT frequency is not limited by f BRT frequency is determined by the minimum BRT on- time of 50µs ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications Table 4. Component Suppliers SUPPLIER Murata Nichia Sumida Toshiba Vishay Inductor Selection The inductance, peak current rating, series resistance, and physical size should all be considered when selecting ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications The minimum inductor value should be recalculated is determined (see the Sense-Resistor after the R S Selection section). Choose an available inductor value from an appropriate inductor family. ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications Output Capacitor Selection The total output voltage ripple has two components: the capacitive ripple caused by the charging and discharging on the output capacitor, and the ohmic ripple ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications Input Capacitor Selection The input capacitor (C ) filters the current peaks drawn IN from the input supply and reduces noise injection into the IC. A 10µF ceramic ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications PCB Layout Guidelines Careful PCB layout is important for proper operation. Use the following guidelines for good PCB layout: 1) Minimize the area of the high current-switching loop ...
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Six-String White LED Driver with Active Current Balancing for LCD Panel Applications (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 22 ______________________________________________________________________________________ Package Information ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 23 © 2007 Maxim Integrated Products Package Information (continued registered trademark of Maxim Integrated Products, Inc ...