ml4871 Microsemi Corporation, ml4871 Datasheet
ml4871
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ml4871 Summary of contents
Page 1
... Continuous conduction allows the regulator to maximize output current for a given inductor. The maximum switching frequency can exceed 200kHz, allowing the use of small, low cost inductors. The ML4871 is capable of start-up with input voltages as low as 1.8V and is available in 5V and 3.3V output versions with an output voltage accuracy of ± ...
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... 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 SOIC (S08 PWR GND RESET GND DETECT OUT TOP VIEW NO ...
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... 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 – 0.2V ...
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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 L2 100µF DETECT V OUT Figure 1. Application Test Circuit SYNCHRONOUS BOOST CONTROL ...
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... V OUT INDUCTOR SELECTION The ML4871 is able to operate over a wide range of inductor values. A value of 10µ good choice, but any value between 5µH and 33µH is acceptable. As the inductor value is changed the control circuitry will automatically adjust to keep the inductor current under control. Choosing an inductance value of less than 10µ ...
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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 be a function of the inductor used. Therefore, to ...
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... V pins and from the output capacitor to the V L2 • Use a single point ground for the ML4871 ground pin, and the input and output capacitors • Separate the ground for the converter circuitry from the ground of the load circuitry and connect at a single point A sample layout is shown in Figure 8 ...
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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 must be determined whether the ML4871 is capable of delivering the output current. This is done using Equation 1: 30 ...
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... OUTPUT VOLTAGE TEMPERATURE RANGE 3.3V 0ºC to 70ºC 5.0V 0ºC to 70ºC 3.3V –20ºC to 70ºC 5.0V –20ºC to 70ºC ML4871 0.006 - 0.010 (0.15 - 0.26) PACKAGE 8-Pin SOIC (S08) 8-Pin SOIC (S08) 8-Pin SOIC (S08) 8-Pin SOIC (S08) DS4871-01 2092 Concourse Drive San Jose, CA 95131 ...