max887h Maxim Integrated Products, Inc., max887h Datasheet

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... Internal 0.6Ω (typ) MOSFET Internal Synchronous Rectifier High-Frequency Current-Mode PWM External SYNC or Internal 300kHz Oscillator Guaranteed 260kHz to 340kHz Internal Oscillator Frequency Limits 2.5µA Shutdown Mode ______________Ordering Information PART MAX887HC/D MAX887HESA Contact factory for availability. Dice are tested __________________Pin Configuration 3.3V OUT TOP VIEW R1 ...

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... REF Output Voltage V Note 1: Guaranteed by design and not production tested. 2 _______________________________________________________________________________________ Operating Temperature Ranges MAX887HC/D.......................................................0°C to +70°C MAX887HESA ...................................................-40°C to +85°C Storage Temperature Range ........................... -65°C to +165°C Lead Temperature (soldering, 10sec) ............................ +300°C = 0° unless otherwise noted.) A MAX CONDITIONS ...

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Step-Down, PWM DC-DC Converter ELECTRICAL CHARACTERISTICS (V+ = +7V, PGND = GND = 0V, SHDN = V+, (T PARAMETER SYMBOL Supply Range Quiescent Supply Current I (PWM Mode) Quiescent Supply Current (PFM Mode) Shutdown Supply Current I V+, SHDN Output ...

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Duty Cycle, Low-Noise, Step-Down, PWM DC-DC Converter ____________________________Typical Operating Characteristics (continued) (Circuit of Figure +25°C, unless otherwise noted.) A EFFICIENCY vs. OUTPUT CURRENT 100 ...

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Step-Down, PWM DC-DC Converter ____________________________Typical Operating Characteristics (continued) (Circuit of Figure +25°C, unless otherwise noted.) A HEAVY-LOAD, PWM-MODE SWITCHING WAVEFORMS 0mA 1 s/div 3.3V, LOAD = 500mA IN OUT ...

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Duty Cycle, Low-Noise, Step-Down, PWM DC-DC Converter _____________________________Typical Operating Characteristics (continued) (Circuit of Figure +25°C, unless otherwise noted.) A LOAD-TRANSIENT RESPONSE s/div 3.3V, IN OUT LOAD = ...

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Step-Down, PWM DC-DC Converter ______________________________________________________________Pin Description PIN NAME SHDN Shutdown, Active-Low, Logic-Level Input. Connect SHDN to V+ for normal operation Feedback Input. Connect resistor voltage divider between the output and GND. 3 REF Reference ...

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Duty Cycle, Low-Noise, Step-Down, PWM DC-DC Converter _______________Detailed Description The MAX887 is a step-down, pulse-width modulation (PWM) DC-DC converter that provides an adjustable output from 1.25V to 10.5V. It accepts inputs from 3.5V to 11V and delivers up to ...

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... PFM mode is used. Output ripple and noise are higher during PFM operation. SYNC Input and Frequency Control The MAX887H comes with an internal oscillator set for a fixed switching frequency of 300kHz. Connect SYNC to VL for normal forced-PWM operation. Do not leave SYNC floating. Connecting SYNC to GND enables Idle Mode operation to reduce supply current at light loads ...

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Duty Cycle, Low-Noise, Step-Down, PWM DC-DC Converter when to turn off this synchronous rectifier. A fourth comparator (ILIM) is used at the P-channel MOSFET switch for overcurrent detection. This protects the sys- tem, external components, and internal MOSFETs under ...

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Step-Down, PWM DC-DC Converter Bypass V+ to GND using a 0.33µF capacitor. Also bypass VL to GND with a 2.2µF capacitor, and VREF to GND using a 0.047µF capacitor. These capacitors should be placed within 0.2in (5mm) of their respective ...

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Duty Cycle, Low-Noise, Step-Down, PWM DC-DC Converter ________________________________________________________Package Information ______________________________________________________________________________________ 0.101mm 0.004in Narrow SO SMALL-OUTLINE H PACKAGE (0.150 in.) INCHES MILLIMETERS DIM MIN MAX MIN A 0.053 0.069 1.35 A1 ...