ml4880 Microsemi Corporation, ml4880 Datasheet
ml4880
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ml4880 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 implement mixed voltage systems and a flyback controller for 12V V generation for PCMCIA slots ...
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... Feedback node, buck regulator Feedback node, buck regulator SHDN C Shutdown input, regulator C 11 SHDN A Shutdown input, regulator Feedback node, regulator ML4880 24-Pin SOIC (S24) CLAMP CLAMP CLAMP PWR GND PWR GND B SENSE ...
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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 the range of 2.5V to 3.5V (output A), and 4. (output B). The output current is set by external components, and can exceed 2A on each supply ...
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... The ON-time is triggered when the current comparator’s output goes high. However, unlike conventional fixed ON-time controllers, the ML4880’s one shot has an inverse relationship with the input voltage as shown in Figure 4. Figure 5 plots the inductor voltage-ON-time product. Note that the volt- second product is nearly constant at voltages above 7V input ...
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... The ON-time is triggered when the current comparator’s output goes high. However, unlike conventional fixed ON-time controllers, the ML4880’s one shot has an inverse relationship with the input voltage as shown in Figure 4. Figure 5 plots the inductor voltage- ON-time product ...
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... Equation 3 rearranged as follows: OUT SENSE IN OUT I (3) OUT MAX 12V FLYBACK 3.3V BUCK ML4880 OUT F I IRC OUT MAX ( L = ratio of inductor ripple current to the OUT OUT MAX ( ) ...
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... MOSFETs, the lower the figure the better. The internal gate drivers of the ( ) ML4880 can drive over 100nC of total gate charge, but (7) 60nC to 70nC is a more practical limit to ensure good MAX ...
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... In high current applications it may necessary to add bulk capacitor and a small 0.1 F ceramic capacitor to bypass V (pin 16) right at the ML4880. IN BUCK REGULATORS — OUTPUT CAPACITOR SELECTION The output capacitors determine the loop stability and the output ripple voltage ...
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... The turns ratio is specified at 1:1 for simplicity and availability. FLYBACK REGULATOR - MOSFET SELECTION The internal gate drive of the ML4880 limits the selection of the switching FET to logic level types with the ON resistance specified at V with a maximum total gate charge of around 70nC. ...
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... It is important to note that the accuracy of these resistors directly affects the accuracy of the output. Use precision resistors and set the nominal voltage approximately high in order to make up for the ML4880’s load regulation. This offset results in the best overall output accuracy over line and load. ...
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... ML4880 CLAMP REG 12 GND V GND Figure 8. Typical Application Circuit ...
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... Series SC & SA Series PL Series HFQ Series SK Series IRF7XXX Series MMSF Series MMDF Series NDS94XX NDS99XX Littlefoot Series Litefoot Series ML4880 PHONE (402) 563-6506 (512) 992-7900 (708) 639-6400 (305) 781-8900 (605) 665-9301 (714) 362-4211 (619) 674-8100 (708) 956-0666 (317) 834-1066 (207) 282-5111 ...
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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 0.398 - 0.412 (7.39 - 7.65) (10.11 - 10.47) 0.095 - 0.107 (2.41 - 2.72) 0.012 - 0.020 0.005 - 0.013 (0.30 - 0.51) SEATING PLANE (0.13 - 0.33) ML4880 0º - 8º 0.022 - 0.042 0.009 - 0.013 (0.56 - 1.07) (0.22 - 0.33) 14 ...
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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. ...