ML4871CS-3 MICRO-LINEAR [Micro Linear Corporation], ML4871CS-3 Datasheet
ML4871CS-3
Related parts for ML4871CS-3
ML4871CS-3 Summary of contents
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GENERAL DESCRIPTION The ML4871 is a continuous conduction boost regulator designed for conversion in multiple cell battery powered systems. Continuous conduction allows the regulator to maximize output current for a given inductor. The maximum switching frequency can ...
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ML4871 PIN CONFIGURATION PIN DESCRIPTION NO. NAME FUNCTION 1 V Boost inductor connection Battery input voltage IN 3 GND Ground 4 DETECT Pulling this pin below 1.25V causes the RESET pin to go low 2 ML4871 8-Pin ...
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... RESET Output Low Voltage Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst case test conditions. OPERATING CONDITIONS Temperature Range ML4871CS-X ............................................. 0ºC to 70ºC ML4871ES-X .......................................... –20ºC to 70ºC V Operating Range IN ML4871CS-X ................................ 1. ML4871ES-X ................................. 2. 0.3V OUT = Operating Temperature Range (Note 1). A CONDITIONS – ...
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ML4871 SENSE 2 START-UP + – Figure 3. Inductor Current and Voltage Waveforms. 4 20µH (Sumida CD75) ML4871 V L1 PWR GND RESET V IN GND V ...
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FUNCTIONAL DESCRIPTION The ML4871 combines a unique form of current mode control with a synchronous rectifier to create a boost converter that can deliver high currents while maintaining high efficiency. Current mode control allows the use of a very small, ...
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ML4871 DESIGN CONSIDERATIONS OUTPUT CAPACITOR The output capacitor filters the pulses of current from the switching regulator. Since the switching frequency will vary with inductance, the minimum output capacitance required to reduce the output ripple to an acceptable level will ...
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DESIGN CONSIDERATIONS INPUT CAPACITOR Due to the high input current drawn at startup and possibly during operation recommended to decouple the input with a capacitor with a value of 47µF to 100µF. This filtering prevents the input ripple ...
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ML4871 DESIGN EXAMPLE In order to design a boost converter using the ML4871 necessary to define a few parameters. For this example, assume that V = 3.0V to 3.6V OUT I = 500mA. OUT(MAX) First, it ...
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... PLACES) 0.055 - 0.061 (1.40 - 1.55) ORDERING INFORMATION PART NUMBER ML4871CS-3 ML4871CS-5 ML4871ES-3 ML4871ES-5 © Micro Linear 1997 registered trademark of Micro Linear Corporation. All other trademarks are the property of their respective owners. Products described herein may be covered by one or more of the following U.S. patents: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; ...