MAX8795AGCJ/V+T Maxim Integrated Products, MAX8795AGCJ/V+T Datasheet
MAX8795AGCJ/V+T
Specifications of MAX8795AGCJ/V+T
Related parts for MAX8795AGCJ/V+T
MAX8795AGCJ/V+T Summary of contents
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... Denotes a lead(Pb)-free/RoHS-compliant package. /V Denotes an automotive-qualified part. Pin Configurations appear at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. TFT-LCD DC-DC Converter with Operational Amplifiers o 2 ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ABSOLUTE MAXIMUM RATINGS IN, CTL to AGND ...................................................-0.3V to +7.5V COMP, FB, FBP, FBN, DEL, REF to AGND ....-0. PGND, BGND to AGND ......................................................±0. PGND ............................................................-0.3V to +20V SUP to ...
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ELECTRICAL CHARACTERISTICS (continued 3V 14V, V PGND IN MAIN SUP unless otherwise noted.) PARAMETER SYMBOL FB Transconductance FB Voltage Gain LX On-Resistance R LX Leakage Current LX Current Limit Current-Sense Transresistance Soft-Start Period Soft-Start ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ELECTRICAL CHARACTERISTICS (continued 3V 14V, V PGND IN MAIN SUP unless otherwise noted.) PARAMETER SYMBOL GATE-OFF LINEAR-REGULATOR CONTROLLER FBN Regulation Voltage FBN Fault Trip Level FBN Input Bias ...
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ELECTRICAL CHARACTERISTICS ( 14V, V PGND IN MAIN SUP PARAMETER SYMBOL IN Supply Range IN Undervoltage-Lockout V Threshold IN Quiescent Current REF Output Voltage REF Undervoltage-Lockout Threshold MAIN STEP-UP REGULATOR Output Voltage Range V ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ELECTRICAL CHARACTERISTICS (continued 3V 14V, V PGND IN MAIN SUP PARAMETER SYMBOL GATE-OFF LINEAR-REGULATOR CONTROLLER FBN Regulation Voltage FBN Effective Load-Regulation Error (Transconductance) FBN Line (IN) Regulation Error ...
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ELECTRICAL CHARACTERISTICS (continued 3V 14V, V PGND IN MAIN SUP unless otherwise noted.) PARAMETER SYMBOL MAIN STEP-UP REGULATOR Output Voltage Range V Operating Frequency Oscillator Maximum Duty Cycle FB Regulation Voltage FB Fault Trip ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ELECTRICAL CHARACTERISTICS (continued 3V 14V, V PGND IN MAIN SUP unless otherwise noted.) PARAMETER SYMBOL GATE-ON LINEAR-REGULATOR CONTROLLER FBP Regulation Voltage FBP Fault Trip Level FBP Input Bias ...
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ELECTRICAL CHARACTERISTICS ( 14V, V PGND IN MAIN SUP PARAMETER SYMBOL IN Supply Range IN Undervoltage-Lockout V Threshold IN Quiescent Current REF Output Voltage REF Undervoltage-Lockout Threshold MAIN STEP-UP REGULATOR Output Voltage Range V ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ELECTRICAL CHARACTERISTICS (continued 3V 14V, V PGND IN MAIN SUP PARAMETER SYMBOL GATE-ON LINEAR-REGULATOR CONTROLLER FBP Regulation Voltage V FBP Effective Load-Regulation Error (Transconductance) FBP Line (IN) Regulation ...
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Figure 5V 14V MAIN STEP-UP EFFICIENCY vs. LOAD CURRENT 13.9V MAIN 100 1000 LOAD CURRENT (mA) STEP-UP REGULATOR ...
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TFT-LCD DC-DC Converter with Operational Amplifiers (Circuit of Figure 5V 14V MAIN GATE-OFF REGULATOR LINE REGULATION 0.4 0.2 0 -0.2 -0.4 -0.6 -0 50mA NEG -1.0 -16 -14 -12 -10 INPUT ...
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Figure 5V 14V MAIN OPERATIONAL-AMPLIFIER LOAD-TRANSIENT RESPONSE MAX8795A toc15 A 0V +50mA B 0mA -50mA 400ns/div A: OUTPUT VOLTAGE, 1V/div, AC-COUPLED B: OUTPUT CURRENT, 50mA/div PIN NAME Switch Input. Source of ...
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TFT-LCD DC-DC Converter with Operational Amplifiers PIN NAME 17 OUT4 Operational-Amplifier 4 Output 18 POS5 Operational-Amplifier 5 Noninverting Input 19 NEG5 Operational-Amplifier 5 Inverting Input 20 OUT5 Operational-Amplifier 5 Output n-Channel Power MOSFET Drain and Switching Node. Connect the inductor ...
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Typical Operating Circuit The MAX8795A typical operating circuit (Figure complete power-supply system for TFT LCDs. The circuit generates a +14V source-driver supply and +25V and V IN 4.5V TO 5.5V C1 22μF 180kΩ LX C12 C11 220μF ...
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TFT-LCD DC-DC Converter with Operational Amplifiers Table 2. Component Suppliers SUPPLIER PHONE Fairchild 408-822-2000 Sumida 847-545-6700 TDK 847-803-6100 Toshiba 949-455-2000 STEP-UP CONTROLLER PGND COMP AGND MAX8795A DRVP GATE-ON CONTROLLER SRC COM SWITCH CONTROL DRN ...
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RESET DOMINANT CLOCK ILIM COMPARATOR SOFT- START SLOPE COMP PWM Σ COMPARATOR OSCILLATOR FAULT COMPARATOR TO FAULT LATCH ERROR AMP 1.14V Figure 3. Step-Up Regulator Functional Diagram voltage, the controller resets the flip-flop and turns off the ...
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TFT-LCD DC-DC Converter with Operational Amplifiers REG P is enabled after the REF voltage exceeds 1.0V. Each time it is enabled, the controller goes through a soft-start routine that ramps up its internal reference DAC in 128 steps. Gate-Off Linear-Regulator ...
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INPUT SOFT- SOFT- SWITCH VOLTAGE START START CONTROL OK BEGINS ENDS ENABLED Figure 6. Power-Up Sequence IN 5μA DEL REF CTL Figure 7. Switch-Control Block ______________________________________________________________________________________ TFT-LCD DC-DC Converter with Operational Amplifiers C . Once the ...
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TFT-LCD DC-DC Converter with Operational Amplifiers 30Ω p-channel switch (Q2) between DRN and COM turns off. If CTL is low, Q1 turns off and Q2 turns on. During steady-state operation, if the output of the main regulator or any of ...
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Choosing an LIR of 0.5 and estimating efficiency of 85% at this operating point: ⎛ ⎞ 2 ⎛ − ⎞ ⎛ ⎜ ⎟ ⎜ ⎟ ⎜ L ...
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TFT-LCD DC-DC Converter with Operational Amplifiers The number of positive charge-pump stages is given by GON DROPOUT = n POS − × MAIN where n is the number of positive charge-pump POS stages ...
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Charge-Pump Output Capacitor Increasing the output capacitance or decreasing the ESR reduces the output ripple voltage and the peak-to- peak transient voltage. With ceramic capacitors, the output voltage ripple is dominated by the capacitance value. Use the following equation to ...
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TFT-LCD DC-DC Converter with Operational Amplifiers and gate-off linear-regulator controllers are 0.1mA. Therefore, the base-to-emitter resistor for both linear regulators should be chosen to set 0.1mA bias current ...
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The largest portions of power dissipation in the step-up regulator are the internal MOSFET, the inductor, and the output diode. If the step-up regulator has 90% efficiency, approximately the power is lost in the internal MOSFET, ...
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TFT-LCD DC-DC Converter with Operational Amplifiers TOP VIEW DRVP DRVN TOP VIEW DRVP DRVN 26 ______________________________________________________________________________________ FBP 25 26 FBN 27 28 MAX8795A DEL 29 CTL 30 DRN 31 COM ...
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For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing per- ...
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TFT-LCD DC-DC Converter with Operational Amplifiers For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different ...
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For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing per- ...
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TFT-LCD DC-DC Converter with Operational Amplifiers For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different ...
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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 ____________________ 31 © 2010 Maxim Integrated Products ...