ML4880CS MICRO-LINEAR [Micro Linear Corporation], ML4880CS Datasheet
ML4880CS
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ML4880CS Summary of contents
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Portable PC/PCMCIA Power Controller GENERAL DESCRIPTION The ML4880 Portable PC and PCMCIA Power Controller is a complete solution for DC/DC power conversion for portable computing systems with single or multiple PCMCIA slots. The device provides two synchronous buck controllers to ...
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ML4880 PIN CONFIGURATION PIN DESCRIPTION PIN# NAME FUNCTION 1 CLAMP B Gate clamp, regulator B 2 CLAMP A Gate clamp, regulator Current sense, regulator C SENSE Current sense, regulator A SENSE 5 I ...
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... Linear Regulator Output Voltage Linear Regulator Load Regulation V Current IN Note 1: Limits are guaranteed by 100% testing, sampling or correlation with worst case test conditions. OPERATING CONDITIONS V Range ..................................................... 5.5V to 18V IN Temperature Range ML4880CS ................................................ ML4880ES ............................................. – 20V + 0. 0.3V REG ) = Operating Temperature Range (Note 1) REG A CONDITIONS ...
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ML4880 FUNCTIONAL DESCRIPTION The ML4880 converts a 5.5V to 18V input to three outputs via two synchronous buck controllers and a flyback controller. The two buck controllers utilize a unique current mode PFM control architecture that generate output voltages in ...
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The oscillator/one shot block generates a constant ON- time and a minimum OFF-time. The OFF-time is extended for as long as the output of the current comparator stays low. Note that the inductor current flows in the current sense resistor ...
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ML4880 or the buck regulator is operating in a discontinuous current mode (DCM). Therefore, the synchronous rectifier comparator is used only for DCM operation. A timing diagram is shown in Figure 2. FLYBACK CONTROLLER A block diagram of the flyback ...
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DESIGN CONSIDERATIONS A typical design can be implemented by using the following design procedure. Note that this procedure is not intended to give final values, but to give a good starting point, and provide the relationships necessary to make trade-off ...
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ML4880 Having determined the values for the inductor and sense resistor, we can now specify the inductor peak current rating. This value is calculated at current limit and at the maximum input voltage, and is given by ...
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BUCK REGULATORS — INPUT CAPACITOR SELECTION The choice of the input capacitor is based on it’s ripple current and voltage ratings rather than its capacitance value. The input capacitor should be a low ESR type and located as close to ...
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ML4880 The relationship of the inductor current to the output current is given by the following equation SENSE OUT SENSE OUT SENSE The inductance ...
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V V OUT IN MAX ( where, F derating factor VR Again a derating factor of 0.8 is typical for most applications. FLYBACK REGULATOR - INPUT CAPACITOR SELECTION The input capacitor should be a low ESR ...
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ML4880 CLAMP REG 12 GND V GND Figure 8. Typical Application Circuit ...
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SUGGESTED VENDORS See Table 1 for a list of suggested component manufacturers. TABLE 1: COMPONENT SUPPLIERS COMPONENT MANUFACTURER SENSE RESISTORS Dale IRC INDUCTORS Coilcraft Coiltronics Dale Premier Magnetics Pulse Engineering Sumida XFMRS, Inc. CAPACITORS AVX Sprague Sanyo Nichicon Panasonic SEMICONDUCTORS ...
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PHYSICAL DIMENSIONS 0.600 - 0.614 (15.24 - 15.60) 24 PIN 0.024 - 0.034 0.050 BSC (0.61 - 0.86) (1.27 BSC) (4 PLACES) 0.090 - 0.094 (2.28 - 2.39) inches (millimeters) Package: S24 24-Pin SOIC 0.291 - 0.301 ...
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... ML4880 ORDERING INFORMATION PART NUMBER ML4880CS ML4880ES © 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; 5,546,017; 5,559,470; 5,565,761; 5,592,128; 5,594,376; Japan: 2598946; 2619299. Other patents are pending. ...