MIC4684YM Micrel Inc, MIC4684YM Datasheet

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... Simple high-efficiency step-down regulator • 3.3V/1.7A converter (60°C ambient) • 12V to 1.8V/2A converter (60°C ambient) • On-card switching regulator • Dual-output ±5V converter • Battery charger Ordering Information Part Number Standard Pb-Free MIC4684BM MIC4684YM V OUT 2.5V/1.5A R1 3.01k 330µF 6.3V R2 3.01k ...

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Micrel, Inc. Pin Configuration Pin Description Pin Number Pin Name GND Detailed Pin Description Switch (SW, pin 1) The switch pin is tied to the emitter of ...

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MIC4684 Absolute Maximum Ratings Supply Voltage (V ), Note 3 ....................................... +34V IN Enable Voltage (V )......................................–0. Steady-State Output Switch Voltage (V Feedback Voltage (V ) .............................................. +12V FB Storage Temperature (T ) ........................ –65°C to +150°C ...

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Micrel, Inc. Test Circuit +12V Shutdown Input Behavior January 2010 Device Under Test 68µ VIN GND FB SOP-8 2,6,7 5 Current Limit Test Circuit OFF GUARANTEED GUARANTEED OFF ON 0.8V 2V TYPICAL TYPICAL ...

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MIC4684 Typical Characteristics (T = 25°C unless otherwise noted Efficiency without Feed OUT Forward Diode 100 12V 24V ...

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Micrel, Inc. Feedback Voltage vs. Temperature 1.210 1.209 1.208 1.207 1.206 1.205 1.204 1.203 V = 12V 1.202 OUT 100mA 1.201 OUT 1.200 TEMPERATURE (°C) Line Regulation 5.08 5.07 5.06 5.05 5.04 5.03 5.02 ...

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MIC4684 Typical 5V SOA with OUT Standard Configuration 2 OUT 0 60° 125° INPUT VOLTAGE (V) SOA Measured on ...

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Micrel, Inc. Functional Characteristics Switching Frequency Foldback 200kHz 70kHz TIME Frequency Foldback The MIC4684 folds the switching frequency back during a hard short circuit condition to reduce the energy per cycle and protect the device. January 2010 V = 12V ...

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MIC4684 Block Diagrams Enable 200kHz Oscillator MIC4684 Functional Description The MIC4684 is a variable duty cycle switch-mode regula- tor with an internal power switch. Refer to the above block diagram. Supply Voltage The MIC4684 operates from a +4V to +30V ...

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Micrel, Inc. Applications Information Adjustable Regulators Adjustable regulators require a 1.23V feedback signal. Rec- ommended voltage-divider resistor values for common output voltages are included in Table 1. For other voltages, the resistor values can be determined using the following formulas: ...

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MIC4684 A worst-case rule of thumb is to assume that 80% of the total output power dissipation is in the MIC4684 ( the diode-inductor-capacitor circuit 0.8 P D(IC 0.8 × 0.95W D(IC) P ...

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Micrel, Inc. Recommended Components for a Given Output Voltage (Feed-Forward Configuration 16V (in feed-forward configuration OUT OUT 5.0V 1.6A 3.01k 976kΩ 6.5V–16V 47µF, 20V 3.3V 1.7A 3.01k 1.78k 4.85V–16V 47µF, ...

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MIC4684 Printed Circuit Board Evaluation Board Optimized for Low Input Voltage by using Feed-Forward Diode Configuration (V Figure 7a. Bottom Side Copper Figure 7c. Bottom Side Silk Screen Abbreviated Bill of Material (Critical Components) Reference Part Number C1 594D156X0035D2T C2, ...

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Micrel, Inc. Recommended Components for a Given Output Voltage (Standard Configuration 30V OUT OUT 5.0V 1.7A 3.01k 976kΩ 8V–30V 3.3V 1.5A 3.01k 1.78k 7V–28V 2.5V 1.5A 3.01k 2.94k 6.5V–23V 1.8V 1.5A ...

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MIC4684 Printed Circuit Board General Purpose Evaluation Board (V Figure 9a. Bottom Side Copper Figure 9c. Bottom Side Silk Screen Abbreviated Bill of Material (Critical Components) Reference Part Number C1 594D156X0035D2T C2, C5 VJ0805Y104KXAAB C6 GRM426X7R334K50 C3 Optional C4 594D337X06R3D2T ...

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... Micrel, Inc. Package Information MICREL INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA + 1 (408) 944-0800 tEl This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. ...