MAX1880EUG+T Maxim Integrated Products, MAX1880EUG+T Datasheet
MAX1880EUG+T
Specifications of MAX1880EUG+T
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MAX1880EUG+T Summary of contents
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... All devices are available in the ultra- thin TSSOP package (1.1mm max height). TFT LCD Notebook Displays TFT LCD Desktop Monitor Panels ________________________________________________________________ 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. Quad-Output TFT LCD DC-DC Converters with Buffer ♦ ...
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Quad-Output TFT LCD DC-DC Converters with Buffer ABSOLUTE MAXIMUM RATINGS IN, SHDN, TGND, FLTSET to GND...........................-0.3V to +6V DRVN to GND .........................................-0. DRVP to GND..........................................-0. PGND to GND.....................................................................±0.3V RDY, SUPB to GND ................................................-0.3V to +14V LX, ...
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ELECTRICAL CHARACTERISTICS (continued) = +3.0V, SHDN = IN SUPP SUPN PGND = GND 0.22µ 1µF, T REF BUF PARAMETER SYMBOL MAIN STEP-UP CONVERTER Main Output Voltage Range V MAIN FB Regulation ...
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Quad-Output TFT LCD DC-DC Converters with Buffer ELECTRICAL CHARACTERISTICS (continued) = +3.0V, SHDN = IN SUPP SUPN PGND = GND 0.22µ 1µF, T REF BUF SYMBOL PARAMETER NEGATIVE CHARGE PUMP (MAX1778/MAX1880/MAX1881/MAX1882 ...
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... FLTSET Input Voltage Range FLTSET Threshold Voltage FLTSET Input Current RDY Output Low Voltage RDY Output High Leakage Thermal Shutdown Dual Mode is a registered trademark of Maxim Integrated Products, Inc. _______________________________________________________________________________________ Quad-Output TFT LCD DC-DC Converters with Buffer = 10V, LDOOUT = FBL, BUF- = BUFOUT, BUF+ = FLTSET = TGND = ...
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Quad-Output TFT LCD DC-DC Converters with Buffer ELECTRICAL CHARACTERISTICS = +3.0V, SHDN = IN SUPP SUPN PGND = GND 0.22µ 1µF, T REF BUF PARAMETER SYMBOL Input Supply Range V IN ...
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ELECTRICAL CHARACTERISTICS (continued) = +3.0V, SHDN = IN SUPP SUPN PGND = GND 0.22µ 1µF, T REF BUF PARAMETER SYMBOL POSITIVE CHARGE PUMP (MAX1778/MAX1880/MAX1881/MAX1882 only) SUPP Input Supply Range V SUPP ...
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Quad-Output TFT LCD DC-DC Converters with Buffer ELECTRICAL CHARACTERISTICS (continued) = +3.0V, SHDN = IN SUPP SUPN PGND = GND 0.22µ 1µF, T REF BUF PARAMETER SYMBOL Input Bias Current I ...
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SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T MAIN 8V OUTPUT VOLTAGE vs. LOAD CURRENT 8.12 8. 3.3V IN 8.04 8. ...
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Quad-Output TFT LCD DC-DC Converters with Buffer = +3.3V, SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T NEGATIVE CHARGE-PUMP EFFICIENCY vs. LOAD CURRENT 100 V = -5V NEG ...
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SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T RIPPLE VOLTAGE WAVEFORMS MAX1778 toc16 8V -5V 20V 1μs/div 8V 200mA, 10mV/div MAIN ...
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Quad-Output TFT LCD DC-DC Converters with Buffer = +3.3V, SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T LDO OUTPUT VOLTAGE vs. LDO INPUT VOLTAGE (INTERNAL LINEAR REGULATOR) 5.05 ...
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SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 100 4.7μF LDOOUT I = 40mA LDOOUT ...
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Quad-Output TFT LCD DC-DC Converters with Buffer = +3.3V, SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T LINEAR-REGULATOR OUTPUT VOLTAGE vs. INPUT VOLTAGE (EXTERNAL LINEAR REGULATOR) 2.55 2.53 ...
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SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T INPUT OFFSET VOLTAGE DEVIATION vs. TEMPERATURE 1 13V SUPB SUPB ...
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Quad-Output TFT LCD DC-DC Converters with Buffer = +3.3V, SHDN = IN, V (Circuit of Figure BUF+ = FLTSET = TGND = PGND = GND, T VCOM BUFFER LARGE-SIGNAL RESPONSE MAX1778 toc48 4.50V 4.00V A 3.50V 4.50V ...
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PIN MAX1778 MAX1880 MAX1883 MAX1885 MAX1881 MAX1882 MAX1884 − − 11 ...
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Quad-Output TFT LCD DC-DC Converters with Buffer PIN MAX1778 MAX1880 MAX1883 MAX1885 MAX1881 MAX1882 MAX1884 − − − − − − ...
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INPUT RDY 4.7μF 100kΩ TO LOGIC LDO LDOOUT C LDO 4.7μF NEGATIVE V = -5V NEG C3 1.0μF Figure 1. Typical Application Circuit Detailed Description The MAX1778/MAX1880–MAX1885 are highly efficient ...
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Quad-Output TFT LCD DC-DC Converters with Buffer Main Step-up Controller During normal pulse-width modulation (PWM) opera- tion, the MAX1778/MAX1880–MAX1885 main step-up controllers switch at a constant frequency of 500kHz or 1MHz (see Selector Guide), allowing the use of low- profile ...
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The switching waveforms will appear noisy and asyn- chronous when light loading causes pulse-skipping operation; this is a normal operating condition that improves light-load efficiency OFF Figure 3. Discontinuous-to-Continuous Conduction Crossover Point V SUPP 2.7V TO 13V ...
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Quad-Output TFT LCD DC-DC Converters with Buffer Negative Charge Pump During the first half-cycle, the P-channel MOSFET turns on, and flying capacitor C X(NEG) minus a diode drop (Figure 4). During the second half- cycle, the P-channel MOSFET turns off, ...
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Figure 6. VCOM Buffer Block Diagram times, the amplifier’s transconductance increases as the output current increases (see Typical Operating Characteristics). The VCOM buffer’s positive feedback input features dual mode operation. The buffer’s output voltage can be internally set by a ...
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Quad-Output TFT LCD DC-DC Converters with Buffer ( the output does not reach regulation within LX(MAX) 1ms, soft-start enters phase II, and the current limit is increased by another 25%. This process is repeated for phase III. The ...
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I includes the primary load current and the MAIN input supply currents for the charge pumps (see Charge-Pump Input Power Considerations), linear regulator, and VCOM buffer. The linear regulator generates an output voltage by dis- sipating power across an ...
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Quad-Output TFT LCD DC-DC Converters with Buffer where η is the efficiency the oscillator frequen- OSC cy (see Electrical Characteristics), and I the primary load current and the input supply currents for the charge pumps (see Charge-Pump Input ...
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Use a Schottky diode with an average current rating equal to or greater than the peak inductor current, and a voltage rating at least 1.5 times the main output volt- age (V ). MAIN Charge Pumps (MAX1778/ MAX1880/ MAX1881/MAX1882 Only) ...
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Quad-Output TFT LCD DC-DC Converters with Buffer Table 2. MAX1881/MAX1882/MAX1884/MAX1885 Component Values (f CIRCUIT MAIN I 100mA MAIN(MAX) V -5V NEG I 2mA NEG V 24V POS I 2mA POS L 4.7µH I >1A ...
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Typical Operating Characteristics). So the maximum efficiency may be approximated by: V η ≅ POS + POS V V SUPD SUPP for the positive charge pump, and: V η ≅ NEG NEG V ...
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Quad-Output TFT LCD DC-DC Converters with Buffer 0.8µA (max). For less than 0.5% error due to FBL input bias current ( must be less than 8kΩ. FBL Capacitor Selection and Regulator Stability Capacitors are required at the input ...
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Input-Output (Dropout) Voltage and Startup A linear regulator’s minimum input-to-output voltage dif- ferential (dropout voltage) determines the lowest use- able supply voltage. Because the MAX1778/ MAX1881/MAX1883/MAX1884 use an internal PNP transistor (or external NPN transistor), their dropout voltage is a ...
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Quad-Output TFT LCD DC-DC Converters with Buffer regulator and charge-pump power ground plane, and the inner layer should contain the analog ground plane and power-ground plane/path for the V buffer and LDO. Connect all three ground COM planes together at ...
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Applications Information Low-Profile Components Notebook applications generally require low-profile components, potentially limiting the circuit’s perfor- mance. For example, low-profile inductors typically have lower saturation ratings and more series resis- tance, limiting output current and efficiency. Low-profile capacitors have lower voltage ...
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Quad-Output TFT LCD DC-DC Converters with Buffer INPUT 4.7μF IN SHDN C1 0.22μF INTG REF C REF 0.22μF R9 30kΩ FLTSET R10 100kΩ PGND Figure 10. Power-Up Sequencing and Fault Protection; converter steps up ...
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INPUT 4.7μF C1 0.22μF C REF 0.22μF Figure 11. VCOM Buffer Soft-Start; the Typical Operating Characteristics. Set the resistive divider to precharge BUFOUT, matching the buffer’s output set voltage: ⎡ ⎛ V SUPB = ...
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Quad-Output TFT LCD DC-DC Converters with Buffer INPUT TO LOGIC LDO OUTPUT NEGATIVE 36 ______________________________________________________________________________________ Typical Operating Circuit IN LX SHDN FB RDY SUPL LDOOUT SUPB SUPN SUPP MAX1778 FBL DRVP DRVN FBP FBN BUFOUT BUFFER OUTPUT BUF- REF BUF+ ...
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Quad-Output TFT LCD DC-DC TOP VIEW INTG BUF MAX1778 BUF MAX1881 SUPB 6 19 BUFOUT 7 18 GND 8 17 REF 9 16 FBP 10 15 FBN 11 ...
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Quad-Output TFT LCD DC-DC Converters with Buffer Chip Information TRANSISTOR COUNT: 3739 38 ______________________________________________________________________________________ ...
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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. 39 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Quad-Output TFT LCD DC/DC ...