MIC2169BYMM Micrel Inc, MIC2169BYMM Datasheet

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... All support documentation can be found on Micrel’s web site at www.micrel.com. ___________________________________________________________________________________________________________ Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • April 2010 MIC2169B 500kHz PWM Synchronous Buck ...

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Micrel, Inc. Typical Application 12V IN SD103BWS 100µF 10µF VDD BST CS VIN HSD MIC2169B VSW COMP/EN 150pF 100nF LSD 1µF FB GND EP MIC2169B Adjustable Output 500kHz Converter April 2010 10µF 0.1µF 0.1µF IRF7821 1.0µH ...

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... Micrel, Inc. Ordering Information Part Number Frequency MIC2169BYMME 500kHz MIC2169BYMM 500kHz Pin Configuration 10-Pin ePad MSOP (MME) Pin Description Pin Number Pin Name 1 VIN 2 VDD COMP/ GND 7 LSD 8 VSW 9 HSD 10 BST ePad EP April 2010 (1) Junction Temperature Range -40° to +125°C -40° to +125°C Pin Function Supply Voltage (Input): +3V to +14 ...

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Micrel, Inc. Absolute Maximum Ratings Supply Voltage (V ) ...................................... -0.3V to 15.5V IN Booststrapped Voltage (V ) .................... -0. BST VSW .............................................................. -0.3V to 15.5V CS ............................................................................15.25V LSD,FB............................................................... -0. Storage Temperature (T )..........................-65°C to +150°C ...

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Micrel, Inc. Electrical Characteristics T = 25° 5V; Bold values indicate –40°C ≤ Parameter Error Amplifier (5) DC Gain Transconductance Soft-Start Soft-Start Current Current Sense CS Over Current Trip Point Temperature Coefficient Gate Drivers Rise/Fall ...

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Micrel, Inc. Typical Characteristics PWM Mode Supply Current vs. Temperature 2.9 2.7 2.5 2.3 2.1 1.9 1.7 1.5 1.3 1.1 0.9 0.7 0.5 -40 - 100120140 TEMPERATURE (°C) V vs. Temperature FB 0.806 0.804 0.802 ...

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Micrel, Inc. Typical Characteristics (continued) Functional Diagram April 2010 Overcurrent Trip Point vs. Temperature 260 240 220 200 180 160 140 120 100 -60 - 120 150 TEMPERATURE (°C) MIC2169B Block Diagram 7 MIC2169B M9999-041210-B ...

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Micrel, Inc. Functional Description The MIC2169B is a voltage-mode, synchronous step- down switching regulator controller designed for high power. Current limit is implemented without the use of an external sense resistor. It includes an internal soft-start function which reduces the ...

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Micrel, Inc HSD Q1 IN MOSFET N 0.1µF RCS Q2 LSD VSW CS MOSFET N 200 A Figure 1. The MIC2169B Current Limiting Circuit The current limiting resistor R CS following equation: × ...

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Micrel, Inc. The following graphs are used to determine the maximum gate charge that can be driven with respect to supply voltage and ambient temperature. Figure 2 shows the power dissipation in the driver for different values of gate charge. ...

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Micrel, Inc. Application Information MOSFET Selection The MIC2169B controller works from input voltages 14.5V and has an internal 5V regulator to provide power to turn the external N-Channel power MOSFETs for high- and low-side switches. For applications ...

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Micrel, Inc. Inductor Selection Values for inductance, peak, and RMS currents are required to select the output inductor. The input and output voltages and the inductance value determine the peak-to-peak inductor ripple current. Generally, higher inductance values are used with ...

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Micrel, Inc. The voltage rating of capacitor should be twice the voltage for a tantalum and 20% greater for aluminum electrolytic. The output capacitor RMS current is calculated below OUT ( rms ) 12 The ...

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Micrel, Inc. Depending on the circuit components and operating conditions, an external Schottky diode will give a ½ improvement in efficiency. Feedback Loop Compensation The MIC2169B controller comes with an internal transconductance error amplifier used for compensating the ...

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Micrel, Inc. It can be seen from Figure 9 that at 50kHz, the phase is approximately –90° versus Figure 10 where the number is –150°. This means that the transconductance error amplifier has to provide a phase boost of about ...

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Micrel, Inc. Figure 13. Open-Loop Gain Margin Figure 14. Open-Loop Phase Margin Pre-Biased Loads The MIC2169B supports pre-biased loads. Some applications have a pre-existing voltage on the output. This pre-existing or pre-biased load is generated by an external supply (other ...

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Micrel, Inc. Figure 17. MIC2169B Startup with Pre-Bias Support, Pre-Bias At 90 Figure 17 shows MIC2169B startup with a pre-bias of 2.2V on the output (90 without the pre-existing OUT output voltage discharge. Design and ...

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Micrel, Inc. MOSFETs • Low gate charge MOSFETs should be used to maximize efficiency, such as Si4800, Si4804BDY, IRF7821, IRF8910, FDS6680A and FDS6912A, etc. RC Snubber • Add a RC snubber of 1.4Ω resistor and a 1000pF capacitor from the ...

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Micrel, Inc. Bill of Materials Item Part Number U1 MIC2169B-YMME Q1, Q2 IRF7821-TR SI4174DY Q3 2N7002E D1 SD103BWS D2 1N5819HW SL04 CMMSH1-40 L1 CDRH127LDNP-1R0NC HC5-1R0 SER1360-1R0 C1 C3225X7R1C106M C2, C3 TPSD686M020R0070 594D686X0020D2T C4 C2012X5R0J106M C5, C10, C12, VJ1206Y104KXXAT C16 C6, ...

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Micrel, Inc. Bill of Materials (continued) Item Part Number R8 CRCW06034021FRT1 R9 CRCW120610R0FRT1 R10 CRCW12062R00FRT1 R12 CRCW12061R40FRT1 R14 J1, J3, J4, J5 2551-2-00-01-00-00-07-0 Notes: 13. Micrel.Inc 408-944-0800 14. Vishay corp 206-452-5664 15. Diodes. Inc 805-446-4800 16. Sumida 408-321-9660 17. TDK ...

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Micrel, Inc. MIC2169B PCB Layout MIC2169B Top Layer April 2010 MIC2169B Bottom Layer 21 MIC2169B M9999-041210-B ...

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Micrel, Inc. Package Information April 2010 10-Pin ePad MSOP (MME) 22 MIC2169B M9999-041210-B ...

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Micrel, Inc. Package Information (continued) April 2010 10-Pin MSOP (MM) 23 MIC2169B M9999-041210-B ...

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Micrel, Inc. MIC2169B Land Patterns April 2010 Recommended Land Pattern for 10-Pin MSOP 24 MIC2169B M9999-041210-B ...

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Micrel, Inc. MIC2169B Land Patterns (continued) MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB The information furnished by Micrel in this data sheet is believed to be accurate and ...