mic4720yml Micrel Semiconductor, mic4720yml Datasheet
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General Description The Micrel MIC4720 is a high efficiency PWM buck (step- down) regulator that provides output current. The MIC4720 operates at 2.0MHz and has proprietary internal compensation that allows a closed loop bandwidth of over ...
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... Micrel, Inc. Ordering Information Part Number MIC4720YML MIC4720YMME Pin Configuration SW 1 VIN 2 PGND 3 SGND 4 BIAS 12-Pin 3mm x 3mm MLF May 2007 Voltage Junction Temp. Range Adj. –40° to +125°C Adj. –40° to +125° VIN 10 PGND 9 PGOOD ...
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Micrel, Inc. Pin Description Pin Number Pin Number ® MLF MSOP — — May 2007 Pin Name Pin Function SW ...
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Micrel, Inc. Absolute Maximum Ratings Supply Voltage (V ) .......................................................+6V IN Output Switch Voltage (V ). .........................................+6V SW Output Switch Current ( ).............................................11A SW Logic Input Voltage (V ) .................................. –0. Storage Temperature (T ) .........................–60°C to ...
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Micrel, Inc. Typical Characteristics MIC4720 1.8V Efficiency OUT OUTPUT CURRENT (A) MIC4720 2.5V ...
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Micrel, Inc. Typical Characteristics (cont.) Feedback Voltage vs. Temperature 1.010 1.008 1.006 1.004 1.002 1.000 0.998 0.996 0.994 0.992 V = 3.3V IN 0.990 TEMPERATURE (°C) Quiescent Current vs. Supply Voltage 800 700 600 500 400 ...
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Micrel, Inc. Functional Characteristics Continuous Current Time (200ns/div) Output Ripple Time (200ns/div) May 2007 OUT L = 1µ 4.7µF OUT I = 1.3A OUT 1.0V ...
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Micrel, Inc. Functional Diagram VIN VIN BIAS Enable and EN Control Logic May 2007 Bias, UVLO, Thermal Shutdown SGND MIC4720 Block Diagram 8 P-Channel Current Limit HSD PWM Control Soft EA Start 1.0V 1.0V PGND MIC4720 PGOOD ...
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Micrel, Inc. Pin Description VIN Two pins for VIN provide power to the source of the internal P-channel MOSFET along with the current limiting sensing. The VIN operating voltage range is from 2.7V to 5.5V. Due to the high switching ...
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Micrel, Inc. Application Information The MIC4720 PWM non-synchronous buck regulator. By switching an input voltage supply, and filtering the switched voltage through an Inductor and capacitor, a regulated DC voltage is obtained. Figure 1 shows a simplified ...
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Micrel, Inc. current flows through the free-wheeling Schottky diode to the output. In this case, the inductor discharge rate is (where V is the diode forward voltage OUT D − L The total off ...
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Micrel, Inc. determines whether the dominant factor in conduction losses will be the internal MOSFET or the Schottky diode. Higher duty cycles place the power losses on the high side switch, and lower duty cycles place the power losses on ...
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Micrel, Inc. Component Selection Input Capacitor A 10µF ceramic is recommended on each VIN pin for bypassing. X5R or X7R dielectrics are recommended for the input capacitor. Y5V dielectrics lose most of their capacitance over temperature and are therefore not ...
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Micrel, Inc. Loop Stability and Bode Analysis Bode analysis is an excellent way to measure small signal stability and loop response in power supply designs. Bode analysis monitors gain and phase of a control loop. This is done by breaking ...
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Micrel, Inc. The following Bode analysis show the small signal loop stability of the MIC4720, it utilizes type III compensation. This is a dominant low frequency pole, followed by 2 zeros and finally the double pole of the inductor capacitor ...
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Micrel, Inc. Max. Amount of Phase Boost Obtainable using C Voltage OUTPUT VOLTAGE (V) By looking at the graph, phase margin can be affected to a ...
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Micrel, Inc. Output Impedance and Transient Response Output impedance, simply stated, is the amount of output voltage deviation vs. the load current deviation. The lower the output impedance, the better. ∆ V OUT = Z OUT ∆ I OUT Output ...
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Micrel, Inc. Ripple measurements To properly measure ripple on either input or output of a switching regulator, a proper ring in tip measurement is required. Standard oscilloscope probes come with a grounding clip long wire with an alligator ...
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Micrel, Inc. Recommended Layout: 2A Evaluation Board May 2007 Recommended Top Layout Recommended Bottom Layout 19 MIC4720 M9999-051707 ...
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Micrel, Inc. MIC4720 Schematic and BOM for 2A Output Item Part Number C1a,C1b C2012JB0J106K GRM219R60J106KE19 08056D106MAT C2 0402ZD104MAT C3 C2012JB0J475K GRM188R60J475KE19 06036D475MAT C4 VJ0402A820KXAA D1 SSA33L L1 RLF7030-1R0N6R4 744 778 9001 IHLP2525AH-01 1 R1,R4 CRCW04021002F R2 CRCW04026651F CRCW04021242F CRCW04022002F CRCW04024022F ...
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Micrel, Inc. Package Information MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http:/www.micrel.com The information furnished by Micrel in this data sheet is believed to be accurate and reliable. ...