MAX8740ETB+T Maxim Integrated Products, MAX8740ETB+T Datasheet
MAX8740ETB+T
Specifications of MAX8740ETB+T
Related parts for MAX8740ETB+T
MAX8740ETB+T Summary of contents
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... THIN DFN 3mm x 3mm ________________________________________________________________ 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. ♦ 90% Efficiency ♦ Adjustable Output from V ♦ 2.6V to 5.5V Input Supply Range ♦ Input Supply Undervoltage Lockout ♦ ...
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TFT-LCD Step-Up DC-DC Converter ABSOLUTE MAXIMUM RATINGS LX to GND ..............................................................-0.3V to +30V IN, SHDN, FREQ GND ...................................-0.3V to +6V COMP GND .......................................-0. Switch Maximum Continuous RMS Current .....................2.4A Continuous Power Dissipation (T ...
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TFT-LCD Step-Up DC-DC Converter ELECTRICAL CHARACTERISTICS (continued 3V 0°C to +85°C. Typical values are at T SHDN IN A PARAMETER CONTROL INPUTS SHDN, FREQ Input Low Voltage V IN SHDN, FREQ Input High Voltage ...
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TFT-LCD Step-Up DC-DC Converter (Circuit of Figure 5V 15V MAIN EFFICIENCY vs. LOAD CURRENT (1.2MHz OPERATION) 100 L = 2.7µ 1.2MHz OSC 3.3V ...
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TFT-LCD Step-Up DC-DC Converter PIN NAME Compensation Pin for Error Amplifier. Connect a series RC from COMP to ground. See the Loop 1 COMP Compensation section for component selection guidelines. Feedback Pin. The FB regulation voltage is 1.24V nominal. Connect ...
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TFT-LCD Step-Up DC-DC Converter SHDN COMP FB 1.24V FREQ OSCILLATOR 5µA Figure 2. Functional Diagram Detailed Description The MAX8740 is a highly efficient power supply that employs a current-mode, fixed-frequency, PWM archi- tecture for fast transient response and low-noise opera- ...
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TFT-LCD Step-Up DC-DC Converter The MAX8740 can be programmed for soft-start upon power-up with an external capacitor. When the shutdown pin is taken high, the soft-start capacitor (C ately charged to 0.4V. Then the capacitor is charged at a constant ...
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TFT-LCD Step-Up DC-DC Converter The equations used here include a constant LIR, which is the ratio of the inductor peak-to-peak ripple current to the average DC inductor current at the full load cur- rent. The best trade-off between inductor size ...
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TFT-LCD Step-Up DC-DC Converter Input Capacitor Selection The input capacitor (C ) reduces the current peaks IN drawn from the input supply and reduces noise injection into the IC. A 10µF ceramic capacitor is used in the typi- cal operating ...
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TFT-LCD Step-Up DC-DC Converter V2 +28V C9 1µ 4. 10µF 10Ω 6.3V C5 1µF C4 33nF Figure 3. Multiple-Output TFT-LCD Power Supply Multiple-Output Power Supply for TFT LCD Figure 3 shows a power supply ...
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TFT-LCD Step-Up DC-DC Converter 3) Place the feedback voltage-divider-resistors as close to the FB pin as possible. The divider’s center trace should be kept short. Placing the resistors far away causes the FB trace to become an antenna that can ...
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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 ____________________ 12 © 2005 Maxim Integrated Products ...