MAX1847EEE+ Maxim Integrated Products, MAX1847EEE+ Datasheet
MAX1847EEE+
Specifications of MAX1847EEE+
Related parts for MAX1847EEE+
MAX1847EEE+ Summary of contents
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... Internal Soft-Start o Electrolytic or Ceramic Output Capacitor o The MAX1847 also offers: Synchronization to External Clock Shutdown N-Channel Inverting Flyback Option PART MAX1846EUB MAX1846EUB+ MAX1847EEE MAX1847EEE+ + Denotes a lead(Pb)-free/RoHS-compliant package. Applications Features Ordering Information TEMP RANGE PIN-PACKAGE -40°C to +85°C 10 µMAX -40°C to +85°C 10 µ ...
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High-Efficiency, Current-Mode, Inverting PWM Controller ABSOLUTE MAXIMUM RATINGS IN, SHDN to GND ...................................................-0.3V to +20V PGND to GND .......................................................-0.3V to +0.3V ≤ 5.7V...........................-0. PGND for PGND for V > 5.7V .......................................-0.3V to ...
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ELECTRICAL CHARACTERISTICS (continued +12V, SYNC = GND, PGND = GND, R SHDN IN otherwise noted.) OSCILLATOR R Oscillator Frequency Maximum Duty Cycle R R SYNC Input Signal Duty-Cycle Range Minimum SYNC Input Logic-Low ...
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High-Efficiency, Current-Mode, Inverting PWM Controller ELECTRICAL CHARACTERISTICS ( +12V, SYNC = GND, PGND = GND, R SHDN IN unless otherwise noted.) (Note 3) PARAMETER PWM CONTROLLER Operating Input Voltage Range V IN UVLO Threshold ...
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ELECTRICAL CHARACTERISTICS (continued +12V, SYNC = GND, PGND = GND, R SHDN IN unless otherwise noted.) (Note 3) PARAMETER POL, SYNC Input Current POL, SYNC = GND SHDN SHDN Input Current V SHDN ...
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High-Efficiency, Current-Mode, Inverting PWM Controller (Circuit references are from Table 1 in the Main Application Circuits section, C noted.) REFERENCE LOAD REGULATION 1.260 1.255 1.250 1.245 1.240 0 100 200 300 400 500 I (µA) REF SHUTDOWN SUPPLY CURRENT vs. ...
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Table 1 in the Main Application Circuits section, C noted.) ENTERING SHUTDOWN SHDN 0 V OUT I L APPLICATION CIRCUIT B 1ms/div LOAD-TRANSIENT RESPONSE I LOAD V OUT I L APPLICATION CIRCUIT B 2ms/div I = ...
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High-Efficiency, Current-Mode, Inverting PWM Controller PIN NAME MAX1846 MAX1847 — 1 POL FREQ 3 4 COMP 4 5 REF — N.C. SHDN — 10, 11 GND 7 12 ...
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V IN +3V to +5.5V 2 0.47µ SHDN 16 SYNC 220pF MAX1847 4 COMP 10kΩ 3 0.22µF FREQ 5 REF 150kΩ POL GND 1 0.1µF _______________________________________________________________________________________ High-Efficiency, Current-Mode, Inverting PWM Controller 3 x 22µF 10V 22kΩ FDS6375 ...
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High-Efficiency, Current-Mode, Inverting PWM Controller IN STARTUP SHDN CIRCUITRY MAX1847 ONLY VL REGULATOR UNDER- VOLTAGE LOCK OUT POL SYNC OSCILLATOR MAX1847 ONLY FREQ COMP FB SOFT-START REF REFERENCE 10 ______________________________________________________________________________________ CONTROL CIRCUITRY ERROR COMPARATOR G M CURRENT- ERROR SENSE AMPLIFIER ...
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Detailed Description The MAX1846/MAX1847 current-mode PWM controllers use an inverting topology that is ideal for generating output voltages from -500mV to -200V. Features include shutdown, adjustable internal operating frequency or synchronization to an external clock, soft-start, adjustable current limit, and ...
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High-Efficiency, Current-Mode, Inverting PWM Controller V +12V 0.47µF 270kΩ 0.033µF 150kΩ Figure 1. Using an N-Channel MOSFET (MAX1847 only) Calculate the Duty Cycle The duty cycle is the ratio of the on-time of the MOSFET switch to the oscillator period. ...
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Higher frequencies allow the use of smaller value (hence smaller size) inductors and capacitors. 3) Higher frequencies consume more operating power both to operate the IC and to charge and discharge the gate at the external FET, which tends ...
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High-Efficiency, Current-Mode, Inverting PWM Controller tance as possible. For continuous inductor current, the power loss in the inductor resistance (P mated by: ⎛ I LOAD ⎜ − ⎝ MAX where R is ...
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The ESR-induced ripple usually dominates this last equation, so typically output capacitor selection is based mostly upon the capacitor’s ESR, voltage rating, and ripple current rating. Use the following formula to determine the maximum ESR for a desired output ripple ...
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High-Efficiency, Current-Mode, Inverting PWM Controller Select the next smaller standard value of resistor and then calculate the compensation capacitor required to cancel out the output-capacitor-induced pole (P determined previously COMP OUT 1 ...
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Under ideal conditions, OUT the RMS current for the input capacitor is the same as the output capacitor. The capacitor value and ESR must be selected to reduce noise to an acceptable value and ...
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High-Efficiency, Current-Mode, Inverting PWM Controller Table 1. Component List for Main Application Circuits CIRCUIT ID A Input (V) 12 Output (V) -5 Output (A) C (µF) 0.047 COMP C (µ (µ 100 OUT ...
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Pin Configurations TOP VIEW + POL FREQ 2 9 EXT MAX1846 FREQ 3 COMP COMP 4 REF 4 7 PGND REF GND FB 6 µMAX N.C. ...
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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. 20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2010 Maxim Integrated Products ...