MIC4681_05 MICREL [Micrel Semiconductor], MIC4681_05 Datasheet
MIC4681_05
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MIC4681_05 Summary of contents
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MIC4681 General Description The MIC4681 SuperSwitcher™ easy-to-use step-down (buck) voltage-mode switching regulator. The 200kHz MIC4681 achieves over 1A of continuous output current over 30V input range in an 8-lead SOPpackage . The MIC4681 features a ...
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MIC4681 Ordering Information Part Number Standard Lead-Free MIC4681BM MIC4681YM Pin Configuration Pin Description Pin Number Pin Name 1 SHDN 2 VIN 5–8 GND MIC4681 Voltage Frequency Junction Temp. Range Adjustable 400kHz SHDN 1 8 GND VIN ...
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MIC4681 Absolute Maximum Ratings Supply Voltage (V ), Note 3 ...................................... +34V IN Shutdown Voltage (V ) .......................... –0.3V to +34V SHDN Steady-State Output Switch Voltage (V Feedback Voltage [Adjustable Storage Temperature (T ) ....................... – ...
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MIC4681 Test Circuit SHUTDOWN Shutdown Input Behavior MIC4681 Device Under Test +30V SHDN FB ENABLE GND SOP-8 5–8 Current Limit Test Circuit ON GUARANTEED ON 0.8V 2V TYPICAL ON 0V 1.25V 1.4V Shutdown Hysteresis ...
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MIC4681 Typical Characteristics Line Regulation 5.05 5.03 5.01 4.99 4.97 Amb = INPUT VOLTAGE (V) Shutdown Current vs. Input Voltage ...
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MIC4681 Shutdown Thresholds vs. Temperature 1.5 Regulator Off Regulator On 1.0 0.5 0.0 -40 - 100 120 TEMPERATURE ( C) MIC4681 V = 12V IN 6 Saturation Voltage vs. Output Current 2 1.5 1 0.5 ...
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MIC4681 April 2005 4681BM SOA 5Vout 4681BM SOA 5Vout 1 1.6 1.4 1.2 1.0 0.8 0.6 0 OUT 0 ...
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MIC4681 Functional Characteristics Switching Frequency Foldback 200kHz 60kHz TIME Frequency Foldback The MIC4681 folds the switching frequency back during a hard short-circuit condition to reduce the energy per cycle and protect the device. MIC4681 Normal Operation Short Circuit Operation 8 ...
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MIC4681 Bode Plots The following bode plots show that the MIC4681 is stable over all conditions using inductor (L) and a 220 F output capacitor ( assure stability good practice to maintain ...
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MIC4681 Block Diagrams MIC4681 SHDN Internal Regulator 200kHz Thermal Current Oscillator Shutdown Limit Com- parator Driver Reset Error 1.23V Amp Bandgap Reference MIC4681 [adj.] Adjustable Regulator OUT REF R2 V OUT R1 ...
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MIC4681 Functional Description The MIC4681 is a variable duty cycle switch-mode regulator with an internal power switch. Refer to the block diagrams. Supply Voltage The MIC4681 operates from a +4V to +30V unregulated input. Highest efficiency operation is from a ...
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MIC4681 Thermal Considerations The MIC4681 SuperSwitcher™ features the power-SOP-8. This package has a standard 8-lead small-outline package profile, but with much higher power dissipation than a stan- dard SOP-8. Micrel's MIC4681 SuperSwitcher™ family are the first dc-to-dc converters to take ...
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MIC4681 T = ambient temperature maximum ambient operating temperature A(max) for the specific design. Calculating the maximum junction temperature given a maximum ambient temperature 1.064 20 C/W + (45 C – 25 ...
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MIC4681 Printed Circuit Board Layouts Figure 6b. Top-Side Silk Screen Figure 6c. Top-Side Copper Abbreviated Bill of Material (Critical Components) Reference Part Number C1 593D226X035E2T C4 594D227X0010D2 C2,C5 VJ0805Y104KXXMB D1 340A L1 CDRH127-680MC U1 MIC4681BM 1 Vishay Dale, Inc., tel: ...
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MIC4681 Applications Circuits* For continuously updated circuits using the MIC4681, see Application Hint 37 at www.micrel.com. J1 +30V max 100nF C1 OFF SHDN ON 35V S1 J3 NKK G12AP GND SOP-8 Figure 7. Constant ...
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MIC4681 Package Information 0.026 (0.65) 0.157 (3.99) 0.150 (3.81) 0.064 (1.63) 0.045 (1.14) MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA + 1 (408) 944-0800 TEL The information furnished by Micrel in this data sheet is believed to ...