MAX1523EUT+T Maxim Integrated Products, MAX1523EUT+T Datasheet
MAX1523EUT+T
Specifications of MAX1523EUT+T
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MAX1523EUT+T Summary of contents
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... Output Fault Protection and Soft-Start o High Efficiency Over 1000 Pin-Selectable Maximum Duty Factor o Micropower Shutdown Mode o Small 6-Pin SOT23 Package o No Current-Sense Resistor PART MAX1522EUT-T MAX1523EUT-T MAX1524EUT-T MAX1522EUT+T MAX1523EUT+T MAX1524EUT+T + Denotes a lead(Pb)-free/RoHS-compliant package. - Denotes a package containing lead(Pb Tape and reel. __________Typical Operating Circuit 50% 85% ...
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Simple SOT23 Boost Controllers ABSOLUTE MAXIMUM RATINGS , FB, SHDN, SET to GND ...................................-0. EXT to GND ................................................-0. Continuous Power Dissipation (T = +70°C) A 6-Pin SOT23 (derate 8.7mW/°C above +70°C) ..........696mW Operating Temperature ...
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A EFFICIENCY vs. LOAD CURRENT (DESIGN EXAMPLE 1) 100 +5V OUT 100 1000 LOAD CURRENT (mA) EFFICIENCY vs. LOAD CURRENT ...
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Simple SOT23 Boost Controllers (T = +25°C, unless otherwise noted.) A SOFT-START RESPONSE 200Ω RESISTIVE LOAD 5V/div OUT 5V/div SHDN 1A/div L LINE-TRANSIENT RESPONSE A ...
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PIN NAME 1 GND Ground 2 FB Feedback Input. Connect FB to external resistive voltage-divider. FB regulates to 1.25V. On-Time Control. Connect SET SET GND to set the fixed 0.5µs on-time (50% duty cycle). See On-Time SET ...
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Simple SOT23 Boost Controllers guarantees startup with input voltages down to 1. The startup oscillator has a fixed 25% duty cycle CC and will toggle the MOSFET gate and begin boosting the output voltage. Once the output ...
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The selection of 30% ripple current causes this to happen at loads less than approximately 1/6th of maximum load. There are two common reasons not to run in CCM: 1) High output voltage. In this case, the ...
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Simple SOT23 Boost Controllers INPUT 3.3V ±10% R3 10Ω C3 0.1µF OFF ON Figure 2. MAX1524 Standard Operating Circuit For CCM, the ideal inductor value is given by: × TYP ( ) ON TYP = L IDEAL ...
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C typically needed. Output ripple due to ESR is: ≅ × RIPPLE ESR ( ) PEAK at light and medium loads, and three times as great at ...
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Simple SOT23 Boost Controllers Optional Feed-Forward Capacitor Selection For proper control of peak inductor current during soft- start and for stable switching, the ripple at FB should be greater than 25mV. Without a feed-forward capaci- tor connected between the output ...
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The MAX1522/MAX1523/MAX1524s’ high switching fre- quency demands a high-speed rectifier. Schottky diodes are recommended for most applications because of their fast recovery time and low forward voltage. Ensure that the diode’s current rating is ade- quate to withstand the diode’s ...
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Simple SOT23 Boost Controllers Table 1. Design Examples Using CCM PARAMETER 3.3V ±10 OUT I 700mA OUT(MAX) 274kΩ, 90.9kΩ R1, R2 Duty Cycle (max) 45.5% t 0.5µs (SET = GND) ON 691kHz to 909kHz f SWITCHING ...
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Table 2. Design Examples Using DCM PARAMETER EXAMPLE 4 V 2. 24V OUT I 30mA OUT(MAX) R1, R2 909kΩ, 49.9kΩ Duty Cycle (max) 89.0% 3µ (SET = 11.9µH IDEAL Sumida ...
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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. 14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2010 Maxim Integrated Products ...