MAX1986ETE+T Maxim Integrated Products, MAX1986ETE+T Datasheet
MAX1986ETE+T
Specifications of MAX1986ETE+T
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MAX1986ETE+T Summary of contents
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... THIN QFN ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Ultra-High-Efficiency White o Synchronous Step-Up Regulator Achieves >95% Efficiency Internal Switch and Synchronous Rectifier Eliminates External MOSFETs and Diodes ...
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Ultra-High-Efficiency White LED Drivers ABSOLUTE MAXIMUM RATINGS OUT, IN, BITA, BITB, BITC, LD1, LD2, LD3, LD4, LD5, LD6, LD7, LD8 to GND ................................-0.3V to +6V LDG to GND........................................................................±0. GND ................................................-0. SETI, REF, MODE, SEL to GND ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 3.3V, SETI = BITA = BITB = BITC = SEL = IN, MODE = GND unless otherwise noted. Typical values are at T PARAMETER SEL Input Logic Low Level ...
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Ultra-High-Efficiency White LED Drivers ELECTRICAL CHARACTERISTICS (Circuit of Figure 3.3V, SETI = BITA = BITB = BITC = SEL = IN, MODE = GND +85°C, unless otherwise noted.) (Note 3) PARAMETER IN Supply Range IN ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 3.3V, SETI = BITA = BITB = BITC = SEL = IN, MODE = GND +85°C, unless otherwise noted.) (Note 3) PARAMETER LD1 to LD8 Regulation Voltage SETI High-Level ...
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Ultra-High-Efficiency White LED Drivers (Circuit of Figure 3.3V, SETI = IN, MODE = IN STEP-UP REGULATOR EFFICIENCY vs. LED CURRENT (8 LEDs) 100 3. 4. ...
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Figure 3.3V, SETI = IN, MODE = IN TOTAL EFFICIENCY vs. INPUT VOLTAGE (4mA LED CURRENT ) 100 LEDs 6 LEDs 50 4 LEDs 40 2.5 3.0 3.5 ...
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Ultra-High-Efficiency White LED Drivers PIN NAME MAX1984 MAX1985 MAX1986 OUT GND — — N. LD1 LD2 LD3 ...
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PIN MAX1984 MAX1985 MAX1986 2. 2.2µF L1 10µ GND REF OUT C3 ...
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Ultra-High-Efficiency White LED Drivers UVLO COMP 2.4V REF C REF MODE DIMMING BITA CONTROL BITB BITC SETI R SETI LED SELECT SEL Figure 2. System Functional Diagram 10 ______________________________________________________________________________________ L FB STEP-UP CONTROLLER MAX1984 MAX1985 ...
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Standard Application Circuits The standard application circuit of the MAX1984 drives eight white LEDs (Figure 1). The standard application cir- cuit of the MAX1985 drives six white LEDs (Figure 6). The standard application circuit of the MAX1986 drives four white ...
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Ultra-High-Efficiency White LED Drivers EN_ IREF 1Ω Figure 3. Current Regulator Functional Diagram for an LED’s presence. The current regulators are enabled and any regulator with an output voltage less than 45mV is detected and is ignored, preventing out- puts ...
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BITB to ground to increase the total time constant. Use the following equation to calculate the total time constant: τ = 0.2MΩ ✕ 0.098ms EXT where C is the external capacitance. EXT The ...
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Ultra-High-Efficiency White LED Drivers The MAX1984/MAX1985/MAX1986 provide a control input (SEL) to selectively turn on one subset, the other subset, or all of the LEDs. SEL is a three-level logic input that can be connected to logic low, logic high, ...
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Input Capacitor Selection The input capacitor reduces the current peaks drawn from the input supply and reduces noise injection into all devices running from that supply. The input voltage source impedance determines the required size of the input capacitor. The ...
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Ultra-High-Efficiency White LED Drivers V IN 2. 2.2µF L1 15µ GND REF OUT C3 0.22µF 13 SETI LD1 V IN MAX1985 LD2 16 BITA LD3 15 BITB LD4 BRIGHTNESS ...
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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 ____________________ 17 © 2003 Maxim Integrated Products ...