MIC4680 Micrel Semiconductor, MIC4680 Datasheet
MIC4680
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MIC4680 Summary of contents
Page 1
... SOP (small outline package). The MIC4680 is available in 3.3V and 5V fixed output ver- sions or adjustable output down to 1.25V. The MIC4680 has an input voltage range 34V, with excellent line, load, and transient response. The regulator performs cycle-by-cycle current limiting and thermal shut- down for protection under fault conditions ...
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... Part Number MIC4680BM MIC4680-3.3BM MIC4680-5.0BM Pin Configuration Pin Description Pin Number Pin Name 1 SHDN 2 VIN 5–8 GND MIC4680 Voltage Junction Temp. Range Adjustable – +125 C 3.3V – +125 C 5.0V – +125 C SHDN 1 8 GND GND SW 3 ...
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... Feedback Voltage [Adjustable Storage Temperature (T ) ....................... – +150 C S ESD, Note 5 Electrical Characteristics V = 12V 500mA bold values indicate – LOAD J Parameter Condition MIC4680 [Adjustable] Feedback Voltage ( 1%) ( 2%) 8V Maximum Duty Cycle V FB Output Leakage Current Quiescent Current V FB MIC4680-3 ...
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... Measured on 1" square of 1 oz. copper FR4 printed circuit board connected to the device ground leads. Note 7. Test +85 C, guaranteed by design, and characterized Test Circuit SHUTDOWN Shutdown Input Behavior MIC4680 = 1A = 0V, see Test Circuit = (regulator off (regulator off (regulator on) = +125 C ...
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... SUPPLY VOLTAGE (V) Saturation Voltage vs. Temperature 1.6 1.4 1.2 1.0 0.8 0 12V IN 0 OUT 0.2 LOAD 0 -50 - 100 125 TEMPERATURE ( C) 12V Output Efficiency 100 90 80 15V 24V 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 OUTPUT CURRENT (A) MIC4680 ...
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... Note. For increased output current, see “Applications Information: Functional Characteristics Switching Frequency Foldback 200kHz 60kHz TIME 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. MIC4680 Safe Operating Area 1.5 Minimum 1 ...
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... MIC4680 Bode Plots The following bode plots show that the MIC4680 is stable over all conditions using inductor (L) and a 220 F output capacitor ( assure stability good practice to maintain a phase margin of greater than 35 . OUT No-Load Stability Phase Margin = 106 5.0V ...
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... Bandgap Reference MIC4680-x.x GND Fixed Regulator SHDN Internal Regulator 200kHz Thermal Current Oscillator Shutdown Limit Com- parator Driver Reset Error 1.23V Amp Bandgap Reference MIC4680 [adj.] Adjustable Regulator OUT 1A C Switch OUT OUT REF ...
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... MIC4680 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 a supply voltage around +15V. See the efficiency curves. ...
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... MIC4680BM SHDN FB D1 GND 5–8 Figure 1a. Adjustable Regulator Circuit µ ...
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... There are two methods of determining the minimum ground plane area required by the MIC4680. Quick Method Make sure that MIC4680 pins 5 though 8 are connected to a ground plane with a minimum area of 6cm plane should be as close to the MIC4680 as possible. The area maybe disributed in any shape around the package or on any pcb layer as long as there is good thermal contact to pins 5 though 8 ...
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... MIC4680 by about 20% at high V is measured. Even higher output current can be achieved by using the C MIC4680 to switch an external FET. See Figure 9 for a 5A supply with current limiting. Layout Considerations Layout is very important when designing any switching regu- lator. Rapidly changing switching currents through the printed circuit board traces and stray inductance can generate volt- age transients which can cause problems ...
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... Figure 6e. Bottom-Side Copper Manufacturer Description 1 AVX 15 F 35V 2 Panasonic 47 F 50V, 8mm AVX 220 F 10V 3 Vishay-Diodes, Inc. Schottky General Semiconductor 4 Coiltronics 68 H, 1.5A, nonshielded 5 Sumida 68 H, 1.5A, nonshielded 5 Sumida 68 H, 1.5A, shielded 6 Micrel Semiconductor 1A 200kHz power-SO-8 buck regulator 13 Micrel Qty 1 11.5mm MIC4680 ...
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... MIC4680 Applications Circuits* For continuously updated circuits using the MIC4680, see Application Hint 37 at www.micrel.com. J1 +34V max 100nF C1 OFF SHDN ON 35V S1 J3 NKK G12AP GND SOP-8 Figure 7. Constant Current and Constant Voltage Battery Charger J1 +12V 20V ...
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... MIC4680 June 2000 15 Micrel MIC4680 ...
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... This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc. MIC4680 MAX) PIN 1 ...