mic4684 Micrel Semiconductor, mic4684 Datasheet
mic4684
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mic4684 Summary of contents
Page 1
... The MIC4684, housed in an SO-8, can replace larger TO-220 and TO-263 packages in many applications. The MIC4684 allows for a high degree of safety. It has a wide input voltage range 30V (34V transient), allowing used in applications where input voltage transients may be present ...
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... The bootstrap pin in conjunction with the external bootstrap capacitor provides a bias voltage higher than the input volt- age to the MIC4684’s main NPN pass element. The bootstrap capacitor sees the dv/dt of the switching action at the SW pin voltage. The bootstrap capacitor then couples the AC voltage back to the BS pin plus the dc offset of V where it is rectifi ...
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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 S ESD Rating ............................................................... Note 3 Electrical Characteristics 12V 5V 500mA OUT OUT Parameter Condition Feedback Voltage (± ...
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... MIC4684 Test Circuit +12V Shutdown Input Behavior M9999-021705 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 OFF ON 0V 1.25V 1.4V Enable Hysteresis 4 Micrel, Inc IN(max) February 2005 ...
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... MIC4684 Typical Characteristics (T = 25°C unless otherwise noted Efficiency without Feed OUT Forward Diode 100 12V 24V OUT 50 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 OUTPUT CURRENT (A) Efficiency vs. Output Current with Feed Forward Diode 100 90 5V OUT 80 3.3V OUT 70 2 ...
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... MIC4684 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 5. 500mA OUT 4. INPUT VOLTAGE (V) M9999-021705 Shutdown Hysteresis vs. Temperature ...
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... 125° INPUT VOLTAGE (V) SOA measured on the MIC4684 Evaluation Board. February 2005 T = 25°C A SOA Measured on the MIC4684 Evaluation Board. Note SOA measured on the MIC4684 Evaluation Board. 7 3.3V SOA with Feed OUT Forward Diode 2 3.3V OUT 0 60° 125° ...
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... MIC4684 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. M9999-021705 V = 12V OUT Normal I = 1.0A to 0.1A OUT Operation Short ...
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... 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 (34V transient) unregulated input. Highest efficiency operation is from a supply voltage around +12V. See the efficiency curves on page 5. Enable/Shutdown The enable (EN) input is TTL compatible ...
Page 10
... JA the ground plane to which the power SOP-8 is attached. Determining Ground-Plane Heat-Sink Area Make sure that MIC4684 pins 2, 6, and 7 are connected to a ground plane with a minimum area of 6cm plane should be as close to the MIC4684 as possible. The area may be distributed in any shape around the package or on any pcb layer as long as there is good thermal contact to pins 2, 6, and 7 ...
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... A circuit with sample layouts are provided. See Figure 7. Gerber files are available upon request. Feed Forward Diode The FF diode (feed forward) provides an external bias source directly to the main pass element, this reduces V allowing the MIC4684 to be used in very low head-room ap- plications I. MIC4684BM ...
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... Vishay-Dale Schottky Schottky 595D476X0020D2T SS23 2A, 30V Schottky Sumida 595D476X0020D2T SS23 2A, 30V Vishay-Dale Schottky Schottky 595D476X0020D2T SS23 to the bootstrap pin 16V MBRX120 1A/20V L1 U1 MIC4684BM 47µ VIN SW C6 0.33µ 50V GND B340A or SOP SS34 ...
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... D1 B340A D2 MBRX120 L1 CDRH104R-470MC U1 MIC4684BM Notes: 1. Vishay Dale, Inc., tel: 1 402-644-4218, http://www.vishay.com 2. Vishay Sprague, Inc., tel: 1 207-490-7256, http://www.vishay.com 3. Diodes Inc, tel: (805) 446-4800, http://www.diodes.com 4. Sumida, tel: (408) 982-9960, http://www.sumida.com 5. Micro Commercial Components, tel: (800) 346-3371 6. Micrel, Inc. tel: (408) 944-0800, http://www.micrel.com February 2005 Figure 7b ...
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... SS34 33µF, 35V 3A, 40V Vishay-Dale Schotty 595D336X0035R2T SS34 33µF, 35V 3A, 40V Vishay-Dale Schotty 595D336X0035R2T SS334 47µF, 25V 3A, 40V Vishay-Dale Schotty 595D476X0025D2T SS334 ( 30V MIC4684BM 47µ VIN SW C6 0.33µ 50V GND B340A or SOP SS34 ...
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... C4 594D337X06R3D2T D1 B340A L1 CDRH104R-470MC U1 MIC4684BM Notes: 1. Vishay Dale, Inc., tel: 1 402-644-4218, http://www.vishay.com 2. Vishay Sprague, Inc., tel: 1 207-490-7256, http://www.vishay.com 3. Diodes Inc, tel: (805) 446-4800, http://www.diodes.com 4. Sumida, tel: (408) 982-9960, http://www.sumida.com 5. Micrel, Inc. tel: (408) 944-0800, http://www.micrel.com February 2005 ...
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... MIC4684 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. ...