IR3651STRPBF International Rectifier, IR3651STRPBF Datasheet
IR3651STRPBF
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IR3651STRPBF Summary of contents
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... Gnd Comp PKG PACKAGE DESIG DESCRIPTION S IR3651SPBF S IR3651STRPBF 12/07/2010 Description The IR3651 is a high voltage PWM controller designed for high performance synchronous Buck DC/DC applications. The IR3651 drives a pair of external N-MOSFETs using a programmable switching frequency up to 400kHz allows flexibility to tune the operation of the IC to meet system ...
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ABSOLUTE MAXIMUM RATINGS (Voltages referenced to GND) • Vcc, DRVcc Supply Voltage ..................................… -0.3V to 20V • Vs Supply Voltage …………………………………….. -0.3V to 150V • Vb Supply Voltage …………………………………….. -0.3V to Vs+20V • OCset …………….…………………………………….. 10mA • Storage Temperature Range ...
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Block Diagram Vcc 11 0.25V Gnd 13 4.17V 4 SYNC Oscillator POR R Reset Dom 3V 20uA 64uA Max SS/SD 3 OCP 3uA Error Comp Error Amp 25K 1.25V 25K Fb 1 Comp 2 ...
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Pin Description Pin Name 1 Fb Inverting input to the error amplifier. This pin is connected directly to the output of the regulator via resistor divider to set the output voltage and provide feedback to the error amplifier. 2 Comp ...
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Recommended Operating Conditions Symbol Definition V Converting Voltage bus V Supply Voltage cc DRV Supply Voltage Supply Voltage Operating Frequency s T Junction Temperature j Electrical Specifications Unless otherwise specified, these specifications apply ...
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Parameter SYM Error Amplifier Input Bias Current I FB Source/Sink Current I(source/Sink) Transconductance gm Soft Start/SD Soft Start Current I SS Shutdown Output SD Threshold Over Current Protection OCSET Current I OCSET Hiccup Current I Hiccup Hiccup Duty Cycle Hiccup(duty) ...
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TYPICAL OPERATING CHRACTERISTICS (-40 Vfb 1.253 1.251 1.249 1.247 1.245 1.243 1.241 1.239 1.237 1.235 -40 -30 -20 - emp [ C ] Icc(dynamic) 6.6 6.3 6 5.7 5.4 5.1 4.8 ...
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TYPICAL OPERATING CHRACTERISTICS (-40 Vcc_UVLO 4.3 4.28 4.26 4.24 4.22 4.2 4.18 4.16 4.14 4.12 4.1 -40 -30 -20 - Dead time 100 90 80 ...
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Circuit Description THEORY OF OPERATION Introduction The IR3651 is a voltage synchronous controller. The output voltage is set by feedback pin (Fb) and the internal reference voltage (1.25V). These are two inputs to error amplifier. The error signal between these ...
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Soft-Start The IR3651 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 rises above its threshold and generate the Power On Ready (POR) signal. The ...
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Over-Current Protection The over current protection is performed by sensing current through the R DS(on) MOSFET. This method enhances the converter’s efficiency and reduce cost by eliminating a current sense resistor. As shown in figure 6, an external resistor (R ...
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Application Information Output Voltage Programming Output voltage is programmed by reference voltage and external voltage divider. The Fb pin is the inverting input of the error amplifier, which is internally referenced to 1.25V. The divider is ratioed to provide 1.25V ...
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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 input ...
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Power MOSFET Selection The IR3651 uses two N-Channel MOSFETs. The selections criteria to meet power transfer requirements is based on maximum drain-source voltage (V ), gate-source drive voltage (V DSS maximum output current, On-resistance R and thermal management. The MOSFET ...
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Feedback Compensation The IR3651 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 -(16 π ...
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Based on the frequency of the zero generated by output capacitor and its ESR versus crossover frequency, the compensation type can be different. The table below compensation types and location of crossover frequency. Compensator F vs. F ESR o type ...
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Layout Consideration The layout is very important when designing high frequency switching converters. Layout will affect noise pickup and can cause a good design to perform with less than expected results. Start to place the power components, make all the ...
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IR WORLD HEADQUARTERS: This product has been designed and qualified for the Industrial market 12/07/2010 Figure A 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 Visit us at www.irf.com for sales contact information Data ...