MAX8726EUE+T Maxim Integrated Products, MAX8726EUE+T Datasheet
MAX8726EUE+T
Specifications of MAX8726EUE+T
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MAX8726EUE+T Summary of contents
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... Passive-Matrix LCD Displays PDAs Digital Still Cameras Camcorders Typical Operating Circuit appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800. For small orders, phone 1-800-835-8769. Triple-Output TFT-LCD ♦ Three Integrated DC-DC Converters ♦ ...
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Triple-Output TFT-LCD DC-DC Converters ABSOLUTE MAXIMUM RATINGS IN, SHDN, TGND to GND .........................................-0.3V to +6V DRVN to GND .........................................-0. DRVP to GND..........................................-0. PGND to GND.....................................................................±0.3V RDY to GND ...........................................................-0.3V to +14V LX, SUPP, SUPN to PGND ...
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ELECTRICAL CHARACTERISTICS (continued) = +3.0V, SHDN = IN SUPP SUPN otherwise noted. Typical values are at T PARAMETER SYMBOL Operating Frequency FBP Regulation Voltage V FBP Input Bias Current I DRVP PCH On-Resistance DRVP NCH ...
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Triple-Output TFT-LCD DC-DC Converters ELECTRICAL CHARACTERISTICS (continued) = +3.0V, SHDN = IN SUPP SUPN unless otherwise noted.) (Note 1) PARAMETER SYMBOL Input Supply Range V Input Undervoltage Threshold V UVLO IN Quiescent Supply Current I ...
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ELECTRICAL CHARACTERISTICS (continued) = +3.0V, SHDN = IN SUPP SUPN unless otherwise noted.) (Note 1) PARAMETER SYMBOL LOGIC SIGNALS SHDN Input Low Voltage SHDN Input High Voltage SHDN Input Current I SHDN RDY Output Low ...
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Triple-Output TFT-LCD DC-DC Converters (Circuit of Figure 3.3V +25°C, unless otherwise noted MAXIMUM NEGATIVE CHARGE-PUMP OUTPUT VOLTAGE vs. SUPPLY VOLTAGE - 20mA NEG - 1mA ...
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Figure 3.3V +25°C, unless otherwise noted MAIN BOOST STARTUP WAVEFORM 2V 0 10V 0 0 1ms/div R = 1kΩ 10V MAIN MAIN MAX1748 POWER-UP SEQUENCING 2ms/div V = 10V, ...
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Triple-Output TFT-LCD DC-DC Converters PIN NAME 8 FBN Negative Charge-Pump Regulator Feedback Input. Regulates to 0V nominal. Active-Low Logic-Level Shutdown Input. Connect SHDN to IN for normal operation. SHDN 9 10 DRVN Negative Charge-Pump Driver Output. Output high level is ...
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OSC INTG C INTG Figure 1. PWM Boost Converter Block Diagram For the main boost regulator, soft-start allows a gradual increase of the internal current-limit level during startup to reduce input surge currents. The MAX1748/MAX8726 divide the soft-start period into ...
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Triple-Output TFT-LCD DC-DC Converters OSC MAX1748 MAX8726 Figure 2. Negative Charge-Pump Block Diagram OSC MAX1748 MAX8726 Figure 3. Positive Charge-Pump Block Diagram 10 ______________________________________________________________________________________ SUPN C5 DRVN FBN + - REF + 1.25V REF C GND PGND ...
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In the MAX1748, the reference powers up first, then the main DC-DC step-up converter powers up with soft- start enabled. Once the main step-up converter reach- es regulation, the negative charge pump turns on. When the negative output voltage reaches ...
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Triple-Output TFT-LCD DC-DC Converters The inductance value is then given by: 2 × × V Efficiency (V IN(MIN) MAIN = L 2 × × V LIR I (MAIN) MAIN(MAX) Considering the typical operating circuit, the maximum DC load current (I ...
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Efficiency Considerations The efficiency characteristics of the MAX1748/MAX8726 regulated charge pumps are similar to a linear regulator. They are dominated by quiescent current at low output currents and by the input voltage at higher output cur- rents (see the Typical ...
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Triple-Output TFT-LCD DC-DC Converters Figure 4. Power Supply Using Cascoded MOSFET 14 ______________________________________________________________________________________ ...
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Triple-Output TFT-LCD DC-DC Converters Typical Operating Circuit 15 ...
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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 © 2004 Maxim Integrated Products Package Information PACKAGE OUTLINE, TSSOP 4 ...