MAX749CSA-T Maxim Integrated Products, MAX749CSA-T Datasheet
MAX749CSA-T
Specifications of MAX749CSA-T
Related parts for MAX749CSA-T
MAX749CSA-T Summary of contents
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... PWM Control Output Voltage Range Set by One Resistor Low, 60µA Max Quiescent Current 15µA Max Shutdown Mode Small Size – 8-Pin SO and Plastic DIP Packages ______________Ordering Information PART MAX749CPA MAX749CSA MAX749C/D MAX749EPA MAX749ESA * Contact factory for dice specifications. __________________Pin Configuration TOP VIEW R ...
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Digitally Adjustable LCD Bias Supply ABSOLUTE MAXIMUM RATINGS V+ ................................................................................-0.3V, +7V CTRL, ADJ, FB, DLOW, DHI, CS.....................-0.3V, (V+ + 0.3V) Continuous Power Dissipation (T = +70°C) A Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW SO (derate 5.88mW/°C above +70°C) .........................471mW ...
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Digitally Adjustable LCD Bias Supply __________________________________________Typical Operating Characteristics (T = +25° 47µH, unless otherwise noted.) A EFFICIENCY vs. OUTPUT CURRENT – PNP 85 80 -12V -24V - 470 BASE R = 0.25 ...
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Digitally Adjustable LCD Bias Supply ____________________________Typical Operating Characteristics (continued +25° 47µH, unless otherwise noted.) A LOAD-TRANSIENT RESPONSE OUTPUT VOLTAGE LOAD CURRENT V = -15V OUT TRANSISTOR = ZTX750 50 s/div V = -15V OUT TRANSISTOR = ...
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Digitally Adjustable LCD Bias Supply +2V TO +6V INPUT RESET 6-BIT POWER-ON COUNTER RESET CTRL LOGIC INCREMENT ADJ ON/OFF BIAS MAX749 Figure 1. Block Diagram, Showing External Circuitry Using a PNP Transistor _______________Detailed Description The MAX749 is a negative-output inverting ...
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Digitally Adjustable LCD Bias Supply Q TRIG MINIMUM OFF-TIME ONE-SHOT FLIP-FLOP S R MAXIMUM ON-TIME ONE-SHOT TRIG Q REF MAX749 Figure 2. Switch-Mode Power-Supply Section Block Diagram Once turned off, a one-shot holds the switch off for a minimum of ...
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Digitally Adjustable LCD Bias Supply ADJ CTRL SHUTDOWN RESET Figure 3. Shutdown-Reset-On-Shutdown Sequence of Operation. The device is not shut down during reset. ADJ CTRL Figure 4. Count-Up Operation ADJ CTRL t RS ...
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Digitally Adjustable LCD Bias Supply +4.5V to +6V 0 INPUT V+ CS MAX749 DHI CTRL DLOW ADJ R2 R1 GND C COMP V = -R1(13.33 A) OUT(MIN -(R1+R2)(13.33 A) OUT(MAX) Figure 8. ...
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Digitally Adjustable LCD Bias Supply Choosing an Inductor Practical inductor values range from 22µH to 100µH, and 47µH is normally a good choice. Inductors with a ferrite core or equivalent are recommended. The induc- tor’s saturation current rating – the ...
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Digitally Adjustable LCD Bias Supply The Sumida CD54-470N (47µH, 720mA, 370mΩ) is suit- able for a wide range of applications, and the larger CD105-470N (47µH, 1.17A, 170mΩ) permits higher cur- rent levels and efficiencies. Diode Selection The MAX749’s high switching ...
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Digitally Adjustable LCD Bias Supply Output Filter Capacitor A 22µF, 30V surface-mount (SMT) tantalum output filter capacitor typically maintains 100mVp-p output ripple when generating -24V at 40mA from a 5V input. Smaller capacitors, down to 10µF, may be used for ...
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Digitally Adjustable LCD Bias Supply _______________________________________________________Package Information ______________________________________________________________________________________ 0° - 15° Plastic DIP PKG. PLASTIC P P ...