IR3637STRPBF International Rectifier, IR3637STRPBF Datasheet
IR3637STRPBF
Specifications of IR3637STRPBF
IR3637STRPBFTR
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IR3637STRPBF Summary of contents
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... ORDERING INFORMATION PKG PACKAGE DESIG DESCRIPTION S IR3637SPBF S IR3637STRPBF Rev. 1.1 06/16/05 DESCRIPTION The IR3637 controller IC is designed to provide a simple synchronous Buck regulator for on-board ap- plications in a small 8-pin SOIC. The output voltage can be precisely regulated using the internal 0.8V reference voltage for low voltage applications. ...
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IR3637SPBF ABSOLUTE MAXIMUM RATINGS Vcc Supply Voltage ................................................ Vc Supply Voltage .................................................. Storage Temperature Range ..................................... Operating Junction Temperature Range ..................... ESD Classification ................................................. Moisture Sensitivity Level ........................................ Caution: Stresses above those listed in “Absolute Maximum Rating” may cause permanent ...
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PARAMETER SYM Error Amp Fb Voltage Input Bias Current I Fb Voltage Input Bias Current I Transconductance g Oscillator Frequency Freq Ramp-Amplitude Voltage V Output Drivers Rise Time, Hdrv, Ldrv Fall Time,Hdrv, Ldrv Dead Band Time T Max Duty Cycle ...
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IR3637SPBF BLOCK DIAGRAM 3V 25uA SS/SD 64uA Max 8 POR 0.8V 25K Error Amp 25K Fb 1 Comp 7 Figure 2 - Simplified block diagram of the IR3637. THEORY OF OPERATION Introduction The IR3637 is a fixed frequency, voltage mode ...
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THEORY OF OPERATION Soft-Start The IR3637 has a programmable soft-start to control the output voltage rise and limit the current surge at the start- up. To ensure correct start-up, the soft-start sequence initiates when the Vc and Vcc rise above ...
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IR3637SPBF APPLICATION INFORMATION Design Example: The following example is a typical application for IR3637. Appliaction circuit is shown in page 12 Vcc = 5V IN Vc=12V V = 1.8V OUT OUT ∆V = 50mV OUT ...
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D×(1-D) ---(3) RMS OUT Where the Duty Cycle, D=V /V OUT IN the RMS value of the input capacitor current. RMS I is the output current for each channel. OUT For I =6A ...
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IR3637SPBF For this design, IRF8910 is a good choice. The device provides two N-MOSFETs in a compact SOIC 8-Pin pack- age. The IRF8910 has the following data 20V DSS I = 10A D R =18.3Ω =4.5V ...
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Note that this method requires that the output capacitor should have enough ESR to satisfy stability requirements. In general the output capacitor’s ESR generates a zero typically at 5kHz to 50kHz which is essential for an ac- ceptable phase margin. ...
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IR3637SPBF For a general solution for unconditionally stability for any type of output capacitors wide range of ESR values we should implement local feedback with a compensa- tion network. The typically used compensation network for voltage-mode controller is ...
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Place second pole at the ESR zero ESR 2π × C × Check if R > too small, increase R and ...
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IR3637SPBF TYPICAL APPLICATION Two Supplies Application: Vc=12V, Vin=Vcc= Gnd 12V Vcc C3 1uF SS/SD U1 IR3637 C6 0.1uF Comp C9 Gnd 1.8nF C11 R4 47pF 16K 150uF 150uF C4 C5 ...
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TYPICAL APPLICATION Single 5V Application C3 C4 Vcc Vc HDrv U1 SS/SD C8 IR3637 LDrv Comp C9 Fb Gnd R4 Figure 12 - Typical application for single 5V Rev. 1.1 06/16/ www.irf.com ...
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IR3637SPBF TYPICAL APPLICATION Two Supplies Application, Vcc=Vc=12V, Vin=5V 12V C3 Vcc Vc HDrv U1 SS/SD C8 IR3637 LDrv Comp C9 Gnd R4 Figure 13 - Typical application using 12V for biasing both Vcc and Vc and 5V for Bus Voltage ...
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TYPICAL OPERATING CHARACTERISTICS Vfb vs. Temperature 800.50 800.00 799.50 799.00 798.50 798.00 797. E/A's Transconductance 0.62 0.6 0.58 0.56 0.54 0.52 0 Temp, C Static Vc Current 4.25 4 3.75 3.5 ...
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IR3637SPBF TYPICAL OPERATING CHARACTERISTICS Dynamic Vc Current 12.75 12.5 12.25 12 11.75 11 Temp, C Fall Time-HDrv Temp ...
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TYPICAL PERFORMANCE CURVES Test Conditions: Vcc=Vin=5V, Vc=12V, Vout=1.8V, Iout=0-7A, Ta=Room Temp, No Air Flow. Unless otherwise specified. Figure 14 - Start up waveforms Ch1: Vin=Vcc, Ch2: Vc, Ch3: Vss, Ch4: Vout Figure 16 - Gates waveforms Ch1: Hdrv, Ch2: Ldrv, ...
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IR3637SPBF TYPICAL OPERATING WAVEFORMS Test Conditions: Vcc=Vin=5V, Vc=12V, Vout=1.8V, Iout=0-7A, Ta=Room Temp, No Air Flow. Unless otherwise specified. Figure 18 - Shutdown by shorting the SS pin Ch1: Hdrv, Ch2: Ldrv, Ch3:SS ILoad=5A Figure 20 - Load Transient (0-5A) Ch1: ...
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TYPICAL PERFORMANCE CURVES Test Conditions: Vcc=Vin=5V, Vc=12V, Vout=1.8V, Iout=0-8A, Ta=Room Temp, No Air Flow. Unless otherwise specified. V c=12V , V cc t=0-8A, F s=40 0kHz ...
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IR3637SPBF 8-Pin Surface Mount, Narrow Body PIN NO NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. 20 (S) SOIC Package DETAIL-A 0.38 ± 0.015 8-PIN SYMBOL MIN MAX A 4.80 ...
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PACKAGE SHIPMENT METHOD PKG PACKAGE DESIG DESCRIPTION S SOIC, NARROW BODY This product has been designed and qualified for the Consumer market. IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 Rev. 1.1 06/16/05 PIN ...