MAX1771CSA+ Maxim, MAX1771CSA+ Datasheet
MAX1771CSA+
Specifications of MAX1771CSA+
Related parts for MAX1771CSA+
MAX1771CSA+ Summary of contents
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... ON/OFF SHDN CS REF V+ FB AGND GND ________________________________________________________________ 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. Low I , Step-Up DC-DC Controller Q o 90% Efficiency for 30mA to 2A Load Currents 24W Output Power o 110µA (max) Supply Current o 5µ ...
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... CERDIP (derate 8.00mW/°C above +70°C) .................640mW Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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Adjustable, High-Efficiency, ELECTRICAL CHARACTERISTICS (continued) ( 0mA LOAD A MIN PARAMETERS SYMBOL FB Input Current I SHDN Input High Voltage V SHDN Input Low Voltage V SHDN Input Current ...
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... EXT RISE/FALL TIME vs. SUPPLY VOLTAGE 250 200 C = 2200pF EXT C = 1000pF EXT 150 C = 446pF EXT C = 100pF EXT 100 SUPPLY VOLTAGE (V) MAXIMUM SWITCH ON-TIME vs. TEMPERATURE 16.5 16.0 15.5 -60 - 120 150 90 TEMPERATURE (°C) MAXIMUM SWITCH ON-TIME/ MINIMUM SWITCH OFF-TIME RATIO vs. TEMPERATURE 8.0 7.5 7.0 6.5 6.0 -60 - 120 150 90 ...
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Adjustable, High-Efficiency, (Circuit of Figure 2a +25°C, unless otherwise noted.) A HEAVY-LOAD SWITCHING WAVEFORMS 2µs/div 900mA 12V IN OUT OUT A: EXT VOLTAGE, 10V/div B: INDUCTOR ...
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... Active-High TTL/CMOS Logic-Level Shutdown Input. In shutdown mode SHDN below V+ (due to the DC path from V+ to the output) and the supply current drops to 5µA maximum. Connect to ground for normal operation. 1.5V Reference Output that can source 100µA for external loads. Bypass to GND with 0.1µF. 5 REF The reference is disabled in shutdown ...
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... Figure 1. Functional Diagram _______________________________________________________________________________________ Low I , Step-Up DC-DC Controller Q range of load currents; and 3) the maximum supply current is only 110µA. The device has a shutdown mode that reduces the supply current to 5µA max. Bootstrapped/Non-Bootstrapped Modes Figure 2 shows the standard application circuits for bootstrapped and non-bootstrapped modes ...
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... PFM converters, the MAX1771 switch uses the com- bination of a peak current limit and a pair of one-shots that set the maximum on-time (16µs) and minimum off- time (2.3µs); there is no oscillator. Once off, the mini- mum off-time one-shot holds the switch off for 2.3µs. ...
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... The control circuitry allows the IC to operate in continu- ous-conduction mode (CCM) while maintaining high efficiency with heavy loads. When the power switch is turned on, it stays on until either 1) the maximum on- time one-shot turns it off (typically 16µs later the switch current reaches the peak current limit set by the current-sense resistor ...
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... OUT = 50mΩ = 100mΩ Figure 4d. Maximum Output Current vs. Input Voltage (V = 24V) OUT Inductors with a ferrite core or equivalent are recom- mended; powder iron cores are not recommended for use with high switching frequencies. Make sure the inductor’s saturation current rating (the current at which ...
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... Use the typical Q results; the maximum value is usually grossly over- specified since guaranteed limit and not the mea- sured value. The typical total gate charge should be 50nC or less. With larger numbers, the EXT pins may not be able to adequately drive the gate ...
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Adjustable, High-Efficiency, Low I , Step-Up DC-DC Controller Q Table 1. Component Suppliers PRODUCTION INDUCTORS Sumida CD54 series CDR125 series Coiltronics Surface Mount CTX20 series Coilcraft DO3316 series DO3340 series Sumida RCH855 series Through Hole RCH110 series SUPPLIER ...
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... LX switch pulses are captured by Schottky diode D2 to boost low input voltage, but also limits the maximum input supply to 11V. If the input voltage does not fall below 4V and logic threshold FET is used for Q1, you may omit D2 and connect V+ directly to the input supply. ...
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Adjustable, High-Efficiency, Low I , Step-Up DC-DC Controller 4.5V TO 15V C1 33µF L1 16V 2 20µH OFF V+ 4 C2* SHDN 1µF ON MAX1771 1 Q1** EXT AGND ...
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Adjustable, High-Efficiency, D03340 220µH–680µ EXT SHDN C5 0.1µ REF 2 MAX1771 AGND GND C6 10µF 100V Figure 7. -48V Input to 5V Output at 300mA, Without a Transformer ...
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... Figure 9. 5V/1A Boost Converter 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. 16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © ...