MAX1518BETJ Maxim Integrated Products, MAX1518BETJ Datasheet
MAX1518BETJ
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MAX1518BETJ Summary of contents
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... Automotive Displays Ordering Information TEMP PART PIN-PACKAGE RANGE -40°C to MAX1518BETJ 32 Thi n QFN +100°C ________________________________________________________________ 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. TFT-LCD DC-DC Converter with Operational Amplifiers ♦ ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ABSOLUTE MAXIMUM RATINGS IN, CTL to AGND ......................................................-0.3V to +7V COMP, FB, FBP, FBN, DEL, REF to AGND ....-0. PGND, BGND to AGND ......................................................±0. PGND ............................................................-0.3V to +14V SUP to ...
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ELECTRICAL CHARACTERISTICS (continued 3V 8V, PGND = AGND = BGND = SUP wise noted.) PARAMETER SYMBOL LX On-Resistance R LX Leakage Current LX Current Limit Current-Sense Transconductance Soft-Start Period Soft-Start Step Size OPERATIONAL ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ELECTRICAL CHARACTERISTICS (continued 3V 8V, PGND = AGND = BGND = SUP wise noted.) FBP Line (IN) Regulation Error DRVP Sink Current I DRVP DRVP Off-Leakage Current ...
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ELECTRICAL CHARACTERISTICS ( 8V, PGND = AGND = BGND = SUP PARAMETER SYMBOL IN Supply Range IN Undervoltage-Lockout Threshold IN Quiescent Current REF Output Voltage MAIN STEP-UP REGULATOR Output Voltage Range Operating Frequency ...
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TFT-LCD DC-DC Converter with Operational Amplifiers ELECTRICAL CHARACTERISTICS (continued 3V 8V, PGND = AGND = BGND = SUP FBP Effective Load-Regulation Error (Transconductance) FBP Line (IN) Regulation Error DRVP Sink Current I DRVP ...
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Figure 5V 13V MAIN unless otherwise noted.) STEP-UP EFFICIENCY vs. LOAD CURRENT 100 13V OUT ...
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TFT-LCD DC-DC Converter with Operational Amplifiers (Circuit of Figure 5V 13V MAIN unless otherwise noted.) GATE-ON REGULATOR LINE REGULATION 0.2 0 -0.2 -0.4 -0 23.5V GON -0 20mA GON ...
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Figure 5V 13V MAIN unless otherwise noted.) OPERATIONAL-AMPLIFIER LOAD-TRANSIENT RESPONSE MAX1518B toc15 0V +50mA 0 -50mA 400ns/div A: OUTPUT VOLTAGE, 1V/div, AC-COUPLED B: OUTPUT CURRENT, 50mA/div PIN NAME Switch Input. Source ...
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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 MAX1518B Typical Operating Circuit (Figure complete power-supply system for TFT LCDs. The cir- cuit generates a +13V source-driver supply and +24V and -8V gate-driver supplies. The input voltage range for the IC is ...
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TFT-LCD DC-DC Converter with Operational Amplifiers V IN 4.5V TO 5.5V C1 22µF R10 10Ω C18 0.1µF 180kΩ 220µF LX 0.1µF 6.8kΩ 0.1µ 332kΩ GOFF -8V/50mA 0.22µF R8 40.2kΩ 1% 0.22µF 0.033µF TO VCOM BACKPLANE ...
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V IN Figure 2. MAX1518B Functional Diagram ______________________________________________________________________________________ TFT-LCD DC-DC Converter with Operational Amplifiers STEP-UP CONTROLLER PGND COMP AGND MAX1518B DRVP GATE-ON CONTROLLER FBP SRC DEL COM SWITCH CONTROL CTL DRN DRVN GATE-OFF CONTROLLER SUP ...
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TFT-LCD DC-DC Converter with Operational Amplifiers CLOCK OSCILLATOR TO FAULT LATCH Figure 3. Step-Up Regulator Functional Diagram This discharge condition forces the current through the inductor to ramp back down, transferring the energy stored in the magnetic field to the ...
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V MAIN DRVP NPN CASCODE TRANSISTOR MAX1518B FBP Figure 4. Using Cascoded npn for Charge-Pump Output Voltages > 28V Gate-Off Linear-Regulator Controller, REG N The gate-off linear-regulator controller (REG analog gain block with an open-drain p-channel output. ...
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TFT-LCD DC-DC Converter with Operational Amplifiers Undervoltage Lockout (UVLO) The undervoltage-lockout (UVLO) circuit compares the input voltage at IN with the UVLO threshold (2.5V rising, 2.30V falling, typ) to ensure the input voltage is high enough for reliable operation. The ...
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IN 5µA DEL REF CTL Figure 7. Switch-Control Block During steady-state operation, if the output of the main regulator or any of the linear-regulator outputs does not exceed its respective fault-detection threshold, the MAX1518B activates an internal fault timer. If ...
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TFT-LCD DC-DC Converter with Operational Amplifiers Design Procedure Main Step-Up Regulator The minimum inductance value, peak current rating, and series resistance are factors to consider when selecting the inductor. These factors influence the con- verter’s efficiency, maximum output load capability, ...
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Output-Capacitor Selection The total output voltage ripple has two components: the capacitive ripple caused by the charging and discharg- ing of the output capacitance, and the ohmic ripple due to the capacitor’s equivalent series resistance (ESR ...
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TFT-LCD DC-DC Converter with Operational Amplifiers STEP-UP CONTROLLER PGND MAX1518B Figure 8. Operation with Output Voltages >13V Using Cascoded MOSFET The number of negative charge-pump stages is given by: − GOFF DROPOUT = ...
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POSITIVE CHARGE-PUMP OUTPUT VOLTAGE vs 3-STAGE CHARGE PUMP 2-STAGE CHARGE PUMP 1-STAGE CHARGE PUMP (V) MAIN Figure 9. Positive Charge-Pump Output ...
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TFT-LCD DC-DC Converter with Operational Amplifiers The transconductance amplifier regulates the output voltage by controlling the pass transistor’s base cur- rent. The total DC loop gain is approximately: × BIAS ≅ × ...
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Applications Information Power Dissipation An IC’s maximum power dissipation depends on the thermal resistance from the die to the ambient environ- ment and the ambient temperature. The thermal resis- tance depends on the IC package, PC board copper area, other ...
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TFT-LCD DC-DC Converter with Operational Amplifiers TOP VIEW AGND PGND OUT1 NEG1 POS1 OUT2 24 ______________________________________________________________________________________ SRC 1 REF MAX1518B ...
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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 ____________________ 25 © 2005 Maxim Integrated Products ...