MAX1677EEE Maxim Integrated Products, MAX1677EEE Datasheet
MAX1677EEE
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MAX1677EEE Summary of contents
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... Fixed-Frequency PWM Operation o Secondary Output Up to +28V or -28V for LCD Bias Programmable Current Limit o 0.7V to 5.5V Input Voltage Range o 20µA Quiescent Current o 1µA Shutdown Current o Low-Battery Comparator o Small 16-Pin QSOP Package PART MAX1677EEE Applications V 0. (UP TO MAIN 16 POUT 15 LX ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter ABSOLUTE MAXIMUM RATINGS OUT, LCDON, ON, POUT, LBI, LBO GND .............................................................-0.3V to +6V CLK/SEL, LCDPOL, REF, LCDFB GND .............................................-0. LCDLX to GND .......................................................-0.3V to +30V ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter ELECTRICAL CHARACTERISTICS (continued 3.3V 0.1µF, POUT = OUT, T OUT REF PARAMETER SYMBOL R LX(ON)N LX On-Resistance R LX(ON)P I LX(PWM) LX Current Limit I LX(PFM) P-Channel ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter ELECTRICAL CHARACTERISTICS (V = 3.3V 0.1µF, POUT = OUT, T OUT REF PARAMETER GENERAL Supply Current Main DC On, LCD Off Supply Current All On, Main DC-DC in PFM ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter (Circuits of Figures 2 and +25°C, unless otherwise noted.) A EFFICIENCY vs. LOAD CURRENT (V = 3.3V) OUT 100 PFM MODE 2.4V ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter (Circuits of Figures 2 and +25°C, unless otherwise noted.) A MAIN BOOST CONVERTER SWITCHING WAVEFORMS (PWM MODE) 2V/ div 100mA/ div 50mV/ div 1µs/div 2.4V , 3.3V , ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter (Circuits of Figures 2 and +25°C, unless otherwise noted.) A MAIN BOOST CONVERTER LINE TRANSIENT 1V/ div 0V 50mV/ div 5ms/div 3V ...
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... Boost DC-DC Converter Power Output. Source of internal P-channel MOSFET main boost-converter 16 POUT synchronous rectifier. Dual Mode is a trademark of Maxim Integrated Products. Detailed Description The MAX1677 is a highly-efficient, dual-output power supply for battery-powered devices. On-chip are two complete step-up DC-DC converters to power main logic and bias an LCD (Figure 1) ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter MAX1677 STARTUP OSC ON REF ON ON REF REFERENCE ISET/POL SENSE POL LCDPOL IN I LCDLX LCDFB GND Figure 1. Functional Block Diagram Table 1. Main Boost Converter Available Output Current ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter R3 10Ω OUT POUT C4 L1 MAX1677 0.1µF 10µH GND LX L2 10µH LCDLX LCDON REF C5 CLK/SEL 0.1µ LCDGND LCDPOL R1 LCDFB PGND R2 Figure 2. LCD Converter ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter During PFM operation, the error comparator detects when the output voltage is out of regulation and sets a flip-flop, turning on the N-channel MOSFET switch (Figure 5). When the inductor current ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter Table 3. Setting LCD Output Polarity and Peak Inductor Current LCD LCDPOL OUTPUT INDUCTOR CURRENT CONNECTED TO: POLARITY Positive OUT Negative GND Positive OUT through 50kΩ Negative GND through 50kΩ off ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter in the 10kΩ to 200kΩ range and calculate R1 using one of the following two equations (for positive or negative output). For a positive LCD output, connect LCDPOL to OUT as ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter Use inductors with a ferrite core or equivalent; powder iron cores are not recommended for use with the MAX1677’s high switching frequencies. The inductor’s incremental saturation rating ideally should exceed the ...
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Compact, High-Efficiency, Dual-Output Step-Up and LCD Bias DC-DC Converter reduce the output filter to 2.2µF. Ceramic capacitors will exhibit lower ripple than equivalent value (or even higher value) tantalums due to lower ESR. Layout Considerations The MAX1677’s high-frequency operation makes ...
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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. 16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products ...