ml4872 Microsemi Corporation, ml4872 Datasheet
ml4872
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ml4872 Summary of contents
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... 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 ML4872 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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... V Boost inductor connection Battery input voltage IN 3 GND Ground 4 SHDN Pulling this pin to V regulator to stop switching, and powers down the control circuitry 2 ML4872 8-Pin SOIC (S08 PWR GND GND SHDN OUT ...
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... Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst case test conditions. OPERATING CONDITIONS Temperature Range ML4872CS-X .............................................. 0ºC to 70ºC ML4872ES-X ........................................... –20ºC to 70ºC V Operating Range IN ML4872CS-X ................................ 1. ML4872ES-X ................................ 2. 0.3V OUT = Operating Temperature Range (Note 1). A CONDITIONS – 0.2V ...
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... ML4872 SENSE 2 START-UP + – A1 SHDN Figure 3. Inductor Current and Voltage Waveforms 4 20µH (Sumida CD75) ML4870 V L1 PWR GND GND V L2 100µF SHDN V OUT 200µF Figure 1. Application Test Circuit SYNCHRONOUS ...
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... I OUT MAX ( INDUCTOR SELECTION The ML4872 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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... ML4872 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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... 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 7. Figure 7. Sample PC Board Layout DESIGN EXAMPLE (Continued) In order to design a boost converter using the ML4872 necessary to define a few parameters. For this example, assume that 500mA. OUT(MAX) First, it must be determined whether the ML4871 is capable of delivering the output current ...
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... ML4872 I OUT(MAX 3.3V IN OUT 1.8 386.2 2.0 451.9 2.2 521.5 2.4 585.9 2.6 651.0 2.8 716.5 3.0 782.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 8 (mA) I OUT 2.4V, V OUT IN 1.0 286.2 2.0 332.1 5.0 379.1 10.0 430.0 20.0 479.0 50.0 525.4 100.0 571.8 200.0 618.5 586.0 665 2.4V 711.7 1.0 758.7 2.0 805.3 5.0 851.9 10.0 899.0 20.0 946.1 50.0 992.7 100.0 200.0 485.0 Table 1. Typical I and Efficiency vs ...
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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 ML4872 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) 2092 Concourse Drive San Jose, CA 95131 Tel: (408) 433-5200 Fax: (408) 432-0295 http://www ...