MIC4680BM Micrel Inc, MIC4680BM Datasheet

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... Negative boost converter • Higher output current regulator using external FET L1 3.3V/1A +5V to +34V 3 68µH C2 220µF 4 SHUTDOWN 16V ENABLE D1 B260A or SS26 MIC4680 1A 200kHz SuperSwitcher™ Buck Regulator MIC4680BM 68µH 15µF 35V 1 4 SHDN FB D1 GND B260A or Power SS26 SOIC-8 5– ...

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... Micrel, Inc. Ordering Information Part Number Standard Pb-Free MIC4680BM MIC4680YM MIC4680-3.3BM MIC4680-3.3YM MIC4680-5.0BM MIC4680-5.0YM Pin Configuration Pin Description Pin Number Pin Name 1 SHDN 2 VIN – 8 GND March 2008 Voltage Junction Temp. Range Adj. –40°C to +125°C 3.3V –40°C to +125°C 5.0V – ...

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Micrel, Inc. Absolute Maximum Ratings (3) Supply Voltage (V ) ..................................................+38V IN Shutdown Voltage (V )............................. –0.3V to +38V SHDN Steady-State Output Switch Voltage (V Feedback Voltage [Adjustable] (V Storage Temperature (T ) .........................–65°C to +150°C s (5) EDS Rating ...

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Micrel, Inc. Parameter Condition Shutdown Input Logic regulator off Level regulator on Shutdown Input Current (regulator off) SHDN (regulator on) SHDN Thermal Shutdown Notes: 1. Exceeding the absolute maximum rating may damage the device. ...

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Micrel, Inc. Typical Characteristics Line Regulation 5. 1.0A 5.05 OUT 5.04 5.03 5.02 5.01 5.00 4.99 4.98 4.97 4. INPUT VOLTAGE (V) Shutdown Current vs. Temperature 4 12V ...

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Micrel, Inc. Functional Characteristics Frequency Foldback The MIC4680 folds the switching frequency back during a hard short-circuit condition to reduce the energy per cycle and protect the device. March 2008 Safe Operating Area 1.5 Minimum 1.4 Current Limit 1.3 1.2 ...

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Micrel, Inc. Bode Plots The following bode plots show that the MIC4680 is stable over all conditions using a 68µF inductor (L) and a 220µF output capacitor ( assure stability good practice to maintain a ...

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Micrel, Inc. Functional Diagrams SHDN March 2008 SHDN Internal Regulator 200kHz Thermal Oscillator Shutdown Com- parator Reset Error 1.23V Amp Bandgap Reference MIC4680-x.x GND Fixed Regulator Internal Regulator 200kHz Thermal Current Oscillator Shutdown Com- parator Reset Error 1.23V Amp Bandgap ...

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Micrel, Inc. Functional Description The MIC4680 is a variable duty cycle switch-mode regulator with an internal power switch. Refer to the block diagrams. Supply Voltage The MIC4680 operates from a +4V to +34V unregulated input. Highest efficiency operation is from ...

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... Nearest available resistor values Figure 1b. Recommended Components for Common Output Voltages March 2008 resistor values for SHUTDOWN OUT − REF 60V Schottky B260A Vishay-Diode, Inc*** or SS26 General Semiconductor 10 MIC4680BM SHDN FB ENABLE GND 5–8 Figure 1a. Adjustable Regulator Circuit L1 68µH 1.5A Coiltronics UP2B-680 or Sumida CDRH125-680MC** or ...

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Micrel, Inc. Thermal Considerations The MIC4680 SuperSwitcher features the power-SOIC- 8. This package has a standard 8-pin small-outline package profile but with much higher power dissipation than a standard SOIC-8. The MIC4680 SuperSwitcher is the first dc-to-dc converter to take ...

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... The feedback pin should be kept as far way from the switching elements (usually L1 and D1) as possible. A circuit with sample layouts is provided. See Figure 6a through 6e. at the ambient is measured +4V to +34V Power SOIC MIC4680BM 68µ SHDN GND B260A optional SOIC-8 5– ...

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... Abbreviated Bill of Materials (Critical Components) Reference Part Number C1 TPSD156M035R0300 ECE-A1HFS470 C4 TPSD227M010R0150 D1 B260A SS26 L1 UP2B-680 CDH115-680MC CDRH124-680MC U1 MIC4680BM Notes: 1. AVX: www.avxcorp.com 2. Panasonic: www.maco.panasonic.co.jp/eccd/index.html 3. Vishay-Diodes, Inc.: www.diodes.com 4. Coiltronics: www.coiltronics.com 5. Sumida: www.sumida.com 6. Micrel, Inc.: www.micrel.com March 2008 Manufacturer Description 1 AVX 15µF 35V 2 Panasonic 47µF 50V, 8mm × 11.5mm AVX 220µ ...

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... Micrel, Inc. Application Circuits For continuously updated circuits using the MIC4680, see Application Hint 37 at www.micrel.com. J1 +34V max. Figure 7. Constant Current and Constant Voltage Battery Charger +4.5V to +17V U1 MIC4680BM MIC4417BM4 SHDN GND SOIC-8 5–8 March 2008 Figure 8. +12V to –12V/150mA Buck-Boost Converter ...

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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. ...