IR3637ASPBF International Rectifier, IR3637ASPBF Datasheet
IR3637ASPBF
Specifications of IR3637ASPBF
Related parts for IR3637ASPBF
IR3637ASPBF Summary of contents
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... C2 HDrv LDrv Fb Figure 1 - Typical application of IR3637A. PIN PARTS PARTS COUNT PER TUBE PER REEL ------- Data Sheet No. 94715 IR3637ASPbF & R Oriantation ------ Fig A 2500 Vout 1 ...
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... IR3637ASPbF 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 Ratings" may cause permanent damage to the device. PACKAGE INFORMATION Fb SS/ Vcc Comp 2 7 LDrv ...
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... During shutdown both drivers turn off. www.irf.com TEST CONDITION SS=3V, Fb=0.6V FB1 SS=0V, Fb=0.6V FB2 m RAMP C =1500pF, Vcc=12V, =1500pF, Vcc=12V Vcc=12V Fb=0.6V, Freq=600KHz ON Fb=1V OFF IR3637ASPbF MIN TYP MAX UNITS -0.1 µA -64 µA 450 600 800 µmho 540 600 660 KHz 1. ...
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... IR3637ASPbF 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 IR3637A. THEORY OF OPERATION Introduction The IR3637A is a fixed frequency, voltage mode syn- chronous controller and consists of a precision refer- ence voltage, an error amplifier, an internal oscillator, a PWM comparator, 0 ...
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... The injecting current drops to zero when soft-start voltage is around 2V and the output volt- age goes into steady state. As shown in Figure 4, the positive pin of feedback UVLO comparator is always higher than 0.4V, therefore, feed- back UVLO is not functional during soft-start. www.irf.com IR3637ASPbF 3V 25uA SS/SD 64uA Max POR ...
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... IR3637ASPbF APPLICATION INFORMATION Design Example: The following example is a typical application for IR3637A. Appliaction circuit is shown in page 12 Vcc = 5V IN Vc=12V V = 1.8V OUT OUT = 50mV ∆V OUT F = 600KHz S 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 0 ...
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... DS(ON) ered for the worst case operation. This is typically given in the MOSFET data sheet. Ensure that the conduction losses and switching losses do not exceed the package ratings or violate the overall thermal budget. IR3637ASPbF ---(4) =1.92A O ), gate- DSS ), maximum output current, On- GS and thermal management ...
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... IR3637ASPbF 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 (Lower FET) DS(ON =13.4Ω =10V (Upper FET) DS(ON) ...
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... The additional pole is given by: ---(11 2π × R The pole sets to one half of switching frequency which results in the capacitor POLE 1 6 ---(12) × for F << P IR3637ASPbF = Resistor Dividers for Output Voltage 6 Programming =16.06KΩ. Choose R =16KΩ ---(13) 2π L × get 1.5nF × POLE × ...
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... IR3637ASPbF 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 shown in Figure 10. V OUT E REF Gain(dB) H( Figure 10 - Compensation network with local feedback and its asymptotic gain plot ...
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... The goal is to localize the high current path to a separate loop that does not interfere with the more sensitive analog control function. These two grounds must be connected together on the PC board layout at a single point. Typical Output Capacitor /2 Electrolytic, Tantalum /2 Tantalum, Ceramic Ceramic ESR IR3637ASPbF 11 ...
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... IR3637ASPbF TYPICAL APPLICATION Two Supplies Application: Vc=12V, Vin=Vcc= Gnd 12V Vcc C3 1uF SS/SD U1 IR3637A C6 0.1uF Comp C9 Gnd 1.5nF C11 R4 47pF 16K Figure 11 - Typical Application for IR3637A 150uF 150uF C4 C5 1uF 1uF Vc Q1 IRF8910 HDrv L1 D1 1.0uH DO3316P-102 LDrv R6 Fb 1.24K ...
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... TYPICAL APPLICATION Single 5V Application C3 C4 Vcc Vc HDrv U1 SS/SD C8 IR3637A LDrv Comp C9 Fb Gnd R4 Figure 12 - Typical application for single 5V www.irf.com IR3637ASPbF 5V L1 Vout C7 13 ...
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... IR3637ASPbF TYPICAL APPLICATION Two Supplies Application, Vcc=Vc=12V, Vin=5V 12V C3 Vcc Vc HDrv U1 SS/SD C8 IR3637A LDrv Comp C9 Gnd R4 Figure 13 - Typical application using 12V for biasing both Vcc and Vc and 5V for Bus Voltage For proper start up the 5V rail needs to start before 12V Vout C7 www.irf.com ...
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... E/A Transconductance 0.620 0.600 0.580 0.560 0.540 0.520 0.500 Temp, C Static Vc Current 4.500 4.000 3.500 3.000 2.500 2.000 Temp, C www.irf.com IR3637ASPbF Soft Start Charge Current -15.00 -16.00 -17.00 -18.00 -19.00 -20.00 -21.00 -22.00 -23.00 -24.00 -25.00 -26.00 -27.00 -28.00 -29.00 -30.00 ...
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... IR3637ASPbF 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, Ch4:Inductor Current ILoad=5A 16 Figure 15 - Start up waveforms Ch1:Vin=Vcc, Ch3:Vss, Ch4:Vout Figure 17 - Gates waveforms ...
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... 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:Vout, Ch4:Step Load Current www.irf.com IR3637ASPbF Figure 19 - Output Voltage Ripple Ch1:Vout, Ch4:Inductor Current ILoad=5A Figure 21 - Load Transient (5-0A) Ch1:Vout, Ch4:Step Load Current 17 ...
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... IR3637ASPbF 8-Pin Surface Mount, Narrow Body PIN NO NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. 18 (S) SOIC Package DETAIL-A 0.38 ± 0.015 8-PIN SYMBOL MIN MAX A 4.80 4.98 1.27 BSC B C 0.53 REF D 0.36 0.46 E 3.81 3.99 F 1.52 1.72 G 0.10 0.25 7 BSC H I 0.19 ...
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... This product has been designed and qualified for the Consumer market. www.irf.com PIN PARTS COUNT PER TUBE Visit us at www.irf.com for sales contact information Data and specifications subject to change without notice. 9/22/2005 IR3637ASPbF PARTS T & R PER REEL Orientation 2500 Fig Feed Direction Figure A TAC Fax: (310) 252-7903 ...