IRDC3811 International Rectifier, IRDC3811 Datasheet

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SupIRBuck TM WIDE-INPUT VOLTAGE, SYNCHRONOUS BUCK REGULATOR Features • Wide Input Voltage Range 2.5V to 21V • Wide Output Voltage Range 0.6V to 12V • Continuous 7A Load Capability • 600kHz High Frequency Operation • Programmable Over-Current-Protection • Hiccup Current ...

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ABSOLUTE MAXIMUM RATINGS (Voltages referenced to GND) • V Supply Voltage IN • Vcc Supply Voltage • Vc Supply Voltage • SW • PGood • Fb,COMP,SS,Vsns • OCSet • AGnd to PGnd • Storage Temperature Range • Operating Junction Temperature ...

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Block Diagram Fig. 3. Simplified block diagram of the IR3811. 10/04/08 PD-60334 IR3811MPbF 3 ...

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Pin Description Pin Name 1 Vp Non-inverting input of error amplifier. This pin can be used for tracking application Inverting input to the error amplifier. This pin is connected directly to the output of the regulator via resistor ...

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Recommended Operating Conditions Symbol Definition V Input Voltage in V Supply Voltage cc V Supply Voltage c V Output Voltage o Note1 I Output Current o T Junction Temperature j Electrical Specifications Unless otherwise specified, these specification apply over Vin=V ...

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Parameter SYM Oscillator Frequency F S Ramp Amplitude V ramp Min Pulse Width D min(ctrl) Max Duty Cycle D max Error Amplifier Input Bias Current I FB1 Input Bias Current I Vp Input Bias Current I FB2 Source/Sink Current I(source/Sink) ...

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TYPICAL OPERATING CHARACTERISTICS (-40 Icc(static) 13.0 12.0 11.0 10.0 9.0 8.0 7.0 -40 - Tem p[oC] Icc(dynamic) 21.0 19.0 17.0 15.0 13.0 -40 - Tem p[oC] Vfb 605.0 600.0 595.0 590.0 585.0 ...

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Circuit Description THEORY OF OPERATION The IR3811 is a voltage synchronous regulator and operates with a fixed 600kHz switching frequency, allowing the use of small external components. The output voltage is set by feedback pin (Fb) and the internal reference ...

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Soft-Start The IR3811 has programmable soft-start to control the output voltage rise and limit the inrush current during start-up. To ensure correct start-up, sequence initiates when Vcc and Vc rise above their threshold and generate the Power On Ready (POR) ...

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Over-Current Protection The over current protection is performed by sensing current through the R DS(on) side MOSFET. This method enhances the converter’s efficiency and reduces cost by eliminating a current sense resistor. As shown in figure 7, an external resistor ...

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Application Information Design Example: The following example is a typical application for the IR3811. The application circuit is shown in page 17 V max ) = ...

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Input Capacitor Selection The input filter capacitor should be selected based on how much ripple the supply can tolerate on the DC input line. The ripple current generated during the on time of upper MOSFET should be provided by the ...

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Feedback Compensation The IR3811 is a voltage mode controller; the control loop is a single voltage feedback path including error amplifier and error comparator. To achieve fast transient response and accurate output regulation, a compensation circuit is necessary. The goal ...

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To cancel one of the LC filter poles, place the zero before the LC filter resonant frequency pole π ...

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Based on the frequency of the zero generated by the output capacitor and its ESR versus crossover frequency, the compensation type can be different. The table below shows the compensation types and location of crossover frequency. Compensator F vs. F ...

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Programming the Current-Limit The Current-Limit threshold can be set by connecting a resistor (R ) from drain of the SET low-side MOSFET to the OCSet pin. The resistor can be calculated by using equation (3). The R has a positive ...

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Typical Application for IR3811 Fig.16: Typical Application circuit for 12V to 0.75V at 7A using ceramic output capacitors 10/04/08 12V to 0.75V @ 7A PD-60334 IR3811MPbF 17 ...

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PCB Metal and Components Placement The lead lands (the 11 IC pins) width should be equal to the nominal part lead width. The minimum lead to lead spacing should be ≥ 0.2mm to minimize shorting. Lead land length should be ...

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Solder Resist It is recommended that the lead lands are Non Solder Mask Defined (NSMD). The solder resist should be pulled away from the metal lead lands by a minimum of 0.025mm to ensure NSMD pads. The land pad should ...

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Stencil Design • The Stencil apertures for the lead lands should be approximately 80% of the area of the lead lads. Reducing the amount of solder deposited will minimize the occurrences of lead shorts. If too much solder is deposited ...

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IR WORLD HEADQUARTERS: This product has been designed and qualified for the Consumer market. 10/04/08 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 Visit us at www.irf.com for sales contact information Data and specifications subject to change ...