MIC25400YML TR Micrel Inc, MIC25400YML TR Datasheet
MIC25400YML TR
Specifications of MIC25400YML TR
Related parts for MIC25400YML TR
MIC25400YML TR Summary of contents
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... Ramp Control is a trademark of Micrel, Inc. MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • January 2011 2A Dual Output PWM Synchronous Buck Features • ...
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Micrel, Inc. Ordering Information Part Number Voltage MIC25400YML Adj Pin Configuration Pin Description Pin Number Pin Name EN/DLY1 January 2011 Switching Frequency Temperature Range 1MHz -40°C to +125°C ...
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Micrel, Inc. Pin Number Pin Name 13 EN/DLY2 PGND2 VIND2 VIND1 24 EP January 2011 Pin Description Enable/Delay 2 (Input): This pin can be used to disable V used to ...
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Micrel, Inc. Absolute Maximum Ratings V to PGND .................................................... –0.3V to 16V PGND........................................ –0.3V to 16V IND1 IND2 V to PGND .................................................. –0. PVDD PGND ............................ –0. ...
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Micrel, Inc. Parameter Condition Oscillator / PWM Switching Frequency Maximum Duty-cycle Minimum On-Time I Error Amplifier (each channel) DC Gain High-side internal MOSFET On Resistance RDS(ON) I Low-side MOSFET driver Pull Up On-Resistance Pull Down; I Into 1000pF ...
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Micrel, Inc. Typical Characteristics I vs. DD_OFF Input Voltage 6 -40°C 5 25° 85° INPUT VOLTAGE (V) Current Limit Threshold vs. Input Voltage 3.20 25°C 3.15 3.10 3.05 3. ...
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Micrel, Inc. Functional Characteristics January 2011 7 MIC25400 M9999-020111-C ...
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Micrel, Inc. Functional Diagram January 2011 PWM Core MIC25400 Block Diagram 8 MIC25400 M9999-020111-C ...
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Micrel, Inc. Functional Description The MIC25400 is a dual output, synchronous buck regulators. Output regulation is performed using a fixed frequency, voltage mode control scheme. The fixed frequency clock drives the two sections 180° out of phase, which reduces input ...
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Micrel, Inc. Soft-start Enable and soft-start waveforms are shown in Figure 2. Figure 2. Soft-start Timing Diagram A capacitor connected to the EN/DLY pin. The SS C capacitor range is 4.7nf to 22nf. Releasing the pin SS ...
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Micrel, Inc. High-side Drive The internal high-side drive circuit is designed to switch the internal N-channel MOSFET. Figure 5 shows a diagram of the high-side MOSFET, gate drive and bootstrap circuit. D2 and C BST circuit, which supplies drive voltage ...
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Micrel, Inc. The following steps can be taken to lower the gate drive impedance, minimize the dv/dt-induced current and lower the FET’s susceptibility to the induced glitch: • Chose a low-side MOSFET with a high C ratio and a low ...
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Micrel, Inc. × REF = R2 − OUT REF Minimum Pulse Width Output voltage is regulated by adjusting the on-time pulse width of the high-side FET. This is accomplished by comparing the error amplifier output with ...
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Micrel, Inc. Application Information Component Selection Inductor The value of inductance is determined by the peak to peak inductor current. Higher values of inductance reduce the inductor current ripple at the expense of a larger inductor. Smaller inductance values allow ...
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Micrel, Inc. Figure 9. Overcurrent waveform Figure 9 shows the low-side MOSFET current waveform. Peak current is measured after a small delay. The equations used to calculate the current limit resistor value are shown below ...
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Micrel, Inc. Proper snubber design requires the parasitic inductance and capacitance be known. A method of determining these values and calculating the damping resistor value is outlined below. 1. Measure the ringing frequency at the switch node which is determined ...
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Micrel, Inc. The MOSFET is subjected voltage. A safety factor of 20% should be added to the V of the MOSFET to account for voltage spikes DS(max) due to circuit parasitics. Generally, 30V MOSFETs are recommended for ...
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Micrel, Inc. The modulator, filter and voltage divider gains can be multiplied together to show the open loop gain of these parts. = ⋅ ⋅ Gvd(s) Gfilter(s) H Gmod This transfer function is plotted in Figure 13. At low frequency, ...
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Micrel, Inc. The G is the DC gain of the error amplifier internally set to 2500 (68dB). As illustrated in Figure 12, there are two compensating zeros. ω internally set with R3 and C3. The ...
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Micrel, Inc. PCB Layout Guidelines Warning!!! To minimize EMI and output noise, follow these layout recommendations. PCB Layout is critical to achieve reliable, stable and efficient performance. A ground plane is required to control EMI and minimize the inductance in ...
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Micrel, Inc. RC Snubber • Place the RC snubber on the same side of the board and as close as possible to the low-side MOSFET. Low-side MOSFET • Low-side drive MOSFET traces (LSD pin-to- MOSFET gate pin) must be short ...
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Micrel, Inc. MIC25400 Evaluation Board Schematic January 2011 22 MIC25400 M9999-020111-C ...
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Micrel, Inc. MIC25400 Bill of Materials Item Part Number C1 12103D226MAT2A C2, C13 12063D106MAT2A C4, C10, C6, 06033D103MAT2A C9 C5 08056D225MAT2A C7 VJ0603Y680KXXMB C8 VJ0603Y470KXXMB C11, C14 08056D226MAT2A C12 06033D105MAT2A C16 VJ0603Y332KXXMB C17 VJ0603Y152KXXMB C18, C19 VJ0603Y102KXXMB D1, D2 SD103BWS ...
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Micrel, Inc. PCB Layout Recommendations January 2011 Top Layer Mid Layer 1 24 MIC25400 M9999-020111-C ...
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Micrel, Inc. January 2011 Mid Layer 2 Bottom Layer 25 MIC25400 M9999-020111-C ...
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Micrel, Inc. Package Information January 2011 ® 24-Pin 4mm x 4mm MLF (ML) 26 MIC25400 M9999-020111-C ...
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Micrel, Inc. Recommended Land Pattern MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB Micrel makes no representations or warranties with respect to the accuracy or completeness of the information ...