ml4890cs-3 Microsemi Corporation, ml4890cs-3 Datasheet
ml4890cs-3
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ml4890cs-3 Summary of contents
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High Efficiency, Low Ripple Boost Regulator GENERAL DESCRIPTION The ML4890 is a high efficiency, PFM (Pulse Frequency Modulation), boost switching regulator connected in series with an integrated LDO (Low Dropout Regulator) that incorporates “Silent Switcher™” technology. This technique incorporates a ...
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ML4890 PIN CONNECTION PIN DESCRIPTION PIN NO. NAME FUNCTION 1 V Battery input voltage 200mV reference output REF 3 GND Analog signal ground 4 V LDO linear regulator output OUT 2 ML4890-5/-3/-T 8-Pin SOIC (S08) V PWR ...
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... Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst case conditions. Storage Temperature Range .................... – +150 C Lead Temperature (Soldering 10s) .......................... +260 C Thermal Resistance ( Plastic SOIC .................................................... 110 C/W OPERATING CONDITIONS Temperature Range ML4890CS-X ............................................ +70 C +0.3V BOOST ML4890ES-X ......................................... – + Operating Range IN ML4890CS-X ...
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ML4890 V IN 100 ONE SHOT S Figure 2. PFM Regulator and LDO Block Diagram (Sumida CD54) ML4890 V PWR GND IN V SHDN REF 1 F GND OUT ...
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FUNCTIONAL DESCRIPTION The ML4890 combines Pulse Frequency Modulation (PFM) and synchronous rectification to create a boost converter that is followed by a low dropout linear regulator (LDO). This combination creates a low output ripple boost converter that is both highly ...
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ML4890 DESIGN CONSIDERATIONS INDUCTOR Selecting the proper inductor for a specific application usually involves a trade-off between efficiency and maximum output current. Choosing too high a value will keep the regulator from delivering the required output current under worst case ...
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For example, a two cell to 5V application requires 40mA of output current while using an inductor with 15% tolerance. The output current should be derated by 25% to 50mA to cover the combined inductor and ON-time tolerances. Assuming that ...
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ML4890 The DC resistance of the inductor should be kept to a minimum to reduce losses. A good rule of thumb is to allow 5 to 10m of resistance for each H of inductance. Also, be aware that the DC ...
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LAYOUT Good PC board layout practices will ensure the proper operation of the ML4890. Important layout considerations include: • Use adequate ground and power traces or planes • Keep components as close as possible to the ML4890 • Use short ...
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ML4890 TABLE 1. MAXIMUM OUTPUT CURRENT AND EFFICIENCY ML4890 (mA) EFFICIENCY PERCENTAGE IN OUT 1.0 30.6 1.5 70.7 2.0 80 1.0 23.8 1.5 56.5 2.0 80.0 2.5 80.0 2.8 80.0 ...
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TABLE 1. MAXIMUM OUTPUT CURRENT AND EFFICIENCY ML4890 (mA) EFFICIENCY PERCENTAGE IN OUT 1.0 13.6 1.5 42.7 2.0 82 1.0 9.3 1.5 31.7 2.0 60.6 2.5 95.7 3.0 137.9 L ...
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... PLACES) 0.055 - 0.061 (1.40 - 1.55) ORDERING INFORMATION PART NUMBER OUTPUT VOLTAGE ML4890CS-T ML4890CS-3 ML4890CS-5 ML4890ES-T ML4890ES-3 ML4890ES-5 © Micro Linear 1997 is a registered trademark of Micro Linear Corporation Products described in this document may be covered by one or more of the following patents, U.S.: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; ...