MAX1747EUP Maxim Integrated Products, MAX1747EUP Datasheet

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... Input Supply o Internal Power MOSFETs o 0.1µA Shutdown Current ) power ON o Internal Soft-Start o Power-Ready Output o Internal Supply Sequencing o Fast Transient Response o Ultra-Thin Solution (No Inductors) o Thin TSSOP Package (1.1mm max) PART MAX1747EUP Applications INPUT TO µC 20 OUT 19 CXP 18 SUPM NEGATIVE 17 CXN ...

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Triple Charge-Pump TFT LCD DC-DC Converter ABSOLUTE MAXIMUM RATINGS IN, SUPM, OUT, TGND to GND................................-0.3V to +6V SHDN........................................................................-0.3V to +1V PGND to GND.....................................................................±0.3V SUPM to IN .........................................................................±0.3V CXN to PGND.........................................-0. CXP to PGND ............................(V - 0.3V ...

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ELECTRICAL CHARACTERISTICS (continued +3.0V SUPM SUPP SUPN 1500pF +5V 0°C to +85°C, unless otherwise noted. Typical values are at T OUT A PARAMETER SYMBOL FBN Input Bias Current ...

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Triple Charge-Pump TFT LCD DC-DC Converter ELECTRICAL CHARACTERISTICS ( +3.0V SUPM SUPP SUPN 1500pF +5V -40°C to +85°C, unless otherwise noted.) (Note 1) OUT A PARAMETER SYMBOL Input ...

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ELECTRICAL CHARACTERISTICS (continued +3.0V SUPM SUPP SUPM 1500pF +5V -40°C to +85°C, unless otherwise noted.) (Note 1) OUT A PARAMETER SYMBOL REFERENCE Reference Voltage V Reference Undervoltage ...

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Triple Charge-Pump TFT LCD DC-DC Converter (Circuit of Figure +3.3V SUPM NO-LOAD SUPPLY CURRENT vs. SWITCHING FREQUENCY 0.5 1.0 1.5 2.0 FREQUENCY (MHz) ...

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Figure +3.3V SUPM MAXIMUM POSITIVE CHARGE-PUMP OUTPUT VOLTAGE vs. SUPPLY VOLTAGE 32V POS(NOMINAL 1mA POS 10mA POS ...

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... The main charge pump uses internal MOSFETs with low R to provide high output current. The adjustable ON output voltage of the main charge pump can be set up to 5.5V with external resistors. The dual low-power charge pumps independently regulate a positive output Pin Description is 125Ω (typ). ON (MHz) OSC , and low level is PGND ...

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... OUT The MAX1747 contains two individual low-power charge pumps. Using a single stage, the first charge pump inverts the supply voltage (V a regulated negative output voltage. The second charge pump doubles the supply voltage (V provides a regulated positive output voltage. The MAX1747 contains internal P-channel and N-channel MOSFETs to control the power transfer ...

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... SUPN OUT is pulled to ground through an internal 10Ω resis- tor. For the low-power charge pumps, the output capacitance and load current determine the rate at which each output voltage will decay. The device acti- vates (see Power-up Sequencing) once SHDN is for- ward biased (minimum of 3µ ...

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... REF and GND. During shutdown, the reference is disabled. The efficiency characteristics of the MAX1747 regulat- ed charge pumps are similar to a linear regulator. They are dominated by quiescent current at low output cur- rents and by the input voltage at higher output currents (see Typical Operating Characteristics) ...

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... For the low-power charge pumps, the output capacitor should be anywhere from 5-times to 20-times larger than the flying capacitor, depending on the ripple toler- ance. Increasing the output capacitance or decreasing the ESR reduces the output ripple voltage and the peak-to-peak transient voltage ...

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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 ____________________ 13 © 2000 Maxim Integrated Products PC board should feature separate analog and power ground areas connected at only one point under the IC ...