IR3856WMTR1PBF International Rectifier, IR3856WMTR1PBF Datasheet
IR3856WMTR1PBF
Specifications of IR3856WMTR1PBF
Related parts for IR3856WMTR1PBF
IR3856WMTR1PBF Summary of contents
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SupIRBuck TM INTEGRATED 6A, SYNCHRONOUS BUCK REGULATOR Features • Greater than 95% Maximum Efficiency • Wide Input Voltage Range 1.5V to 16V • Wide Output Voltage Range 0.7V to 0.9*Vin • Continuous 6A Load Capability • Integrated Bootstrap-diode • High ...
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... PACKAGE INFORMATION 4mm x 5mm POWER QFN Boot Enable Seq ORDERING INFORMATION PACKAGE DESIGNATOR M M Rev 8 PGnd 14 10 PVcc Gnd 16 8 PGood COMP Gnd Rt SS/SD OCSet PACKAGE PIN COUNT DESCRIPTION IR3856WMTRPbF 17 IR3856WMTR1PbF 17 PD-97506 IR3856WMPbF and -40 C θ Sync _ FET ) θ Ctrl _ FET ) o θ ...
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Block Diagram Fig. 2. Simplified block diagram of the IR3856W Rev 8.0 PD-97506 IR3856WMPbF 3 ...
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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 ...
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Recommended Operating Conditions Symbol Definition V Input Voltage Supply Voltage cc cc Boot to SW Supply Voltage V Output Voltage o I Output Current o Fs Switching Frequency T Junction Temperature j Electrical Specifications Unless ...
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Electrical Specifications (continued) Unless otherwise specified, these specifications apply over 4.5V< PVcc C<T < 125 C. Typical values are specified Parameter Symbol Oscillator Rt Voltage Frequency F S Ramp Amplitude Vramp Ramp Offset Ramp ...
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Electrical Specifications Unless otherwise specified, these specifications apply over 4.5V< PVcc C<T < 125 C. Typical values are specified Parameter SYM Thermal Shutdown Thermal Shutdown Hysteresis Power Good Power Good upper VPG(upper) Threshold Upper ...
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TYPICAL OPERATING CHARACTERISTICS (-40 Icc(Standby) 290 270 250 230 210 190 170 150 -40 - Temp[ C] FREQUENCY 550 540 530 520 510 500 490 480 470 460 450 -40 - ...
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TYPICAL OPERATING CHARACTERISTICS (-40 Ipcc(Standby) 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 -40 - Temp[ C] Rdson of MOSFETs Over Temperature at Vcc= ...
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Typical Efficiency and Power Loss Curves Vin=12V, Vcc=5V, Io=1A-6A, F The table below shows the inductors used for each of the output voltages in the efficiency measurement. Vo (V) L (uH) 0.9 0.68 1.0 0.68 1.1 0.82 1.2 0.82 1.5 ...
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Typical Efficiency and Power Loss Curves Vin=5V, Vcc=5V, Io=1A-6A The table below shows the inductors used for each of the output voltages in the efficiency measurement. Vo (V) L (uH) 0.7 0.56 0.75 0.56 0.9 0.56 1.0 0.56 ...
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Circuit Description THEORY OF OPERATION Introduction The IR3856W uses a PWM voltage mode control scheme with external compensation to provide good noise immunity and maximum flexibility in selecting inductor values and capacitor types. The switching frequency is programmable from 250kHz ...
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Fig. 3c. Recommended startup sequence, Sequenced operation Pre-Bias Startup IR3856W is able to start up into pre-charged output, which prevents oscillation disturbances of the output voltage. The output starts in asynchronous fashion and keeps the synchronous MOSFET off until the ...
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Operating Frequency The switching frequency can be programmed between 250kHz – 1200kHz by connecting an external resistor from R pin to Gnd. Table 1 t tabulates the oscillator frequency versus R Table 1. Switching Frequency and I External Resistor (R ...
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Thermal Shutdown Temperature sensing is provided IR3856W. The trip threshold is typically set to o 140 C. When trip threshold is exceeded, thermal shutdown turns off both MOSFETs discharges the soft start capacitor. Automatic restart is initiated when the sensed ...
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TIMING DIAGRAM OF PGOOD FUNCTION Fig.9a IR3856W Non-Tracking Operation (Seq=Vcc) Fig.9b IR3856W Tracking Operation Rev 8.0 PD-97506 IR3856WMPbF 16 ...
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Minimum on time Considerations The minimum ON time is the shortest amount of time for which the Control FET may be reliably turned on, and this depends on the internal timing delays. For the IR3856W, the typical minimum on-time is ...
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Application Information Design Example: The following example is a typical application for IR3856W. The application circuit is shown on page 24 13.2V max 1 ≤ ...
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Vc across C6 remains approximately unchanged and the voltage at the Boot pin becomes ≅ + − .......... .......... .......... Boot Fig. 12. Bootstrap circuit to generate Vc voltage A bootstrap ...
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Output Capacitor Selection The voltage ripple and transient requirements determine the output capacitors type and values. The criteria is normally based on the value of the Effective Series Resistance (ESR). However the actual capacitance value and the Equivalent Series Inductance ...
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V Z OUT E REF Gain(dB) H( Fig. 14. Type II compensation network and its asymptotic gain plot The transfer function ( given by: e ...
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V OUT E REF Gain(dB) H( Fig.15. Type III Compensation network and its asymptotic gain plot The ...
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Detailed calculation of compensation Type-III o Θ = Desired Phase Margin 70 − Θ 1 sin = = F F 17.63 kHz Θ 1 sin + Θ 1 sin = = F F 567.1 kHz P ...
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... X7R, 10% Panasonic Thick Film, 0603,1/10W,1% Rohm Thick Film, 0603,1/10W,1% Rohm Thick Film, 0603,1/10W,1% Rohm 0603, 50V, X7R, 10% Panasonic 0603, 16V, X5R, 20% Panasonic SupIRBuck, 6A, PQFN 4x5mm International Rectifier IR3856WMPbF PD-97506 IR3856WMPbF Part Number EEV-FK1E331P C3216X5R1E106M ECJ-1VB1E104K SPM6550T-1R0M100A ECJ-2FB0J226ML MCR03EZPFX4992 MCR03EZPFX7501 MCR03EZPFX2372 MCR03EZPFX2671 ...
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TYPICAL OPERATING WAVEFORMS Vin=12.0V, Vcc=5V, Vo=1.8V, Io=0-6A, Room Temperature, No Air Flow Fig. 17. Start Load :Enable Fig. 19. Start ...
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TYPICAL OPERATING WAVEFORMS Vin=12V, Vcc=5V, Vo=1.8V, Io=3A-6A, Room Temperature, No Air Flow Fig. 23. Transient Response step Rev 8.0 IR3856WMPbF 2.5A/μ PD-97506 26 ...
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TYPICAL OPERATING WAVEFORMS Vin=12V, Vcc=5V, Vo=1.8V, Io=6A, Room Temperature, No Air Flow Fig. 24. Bode Plot at 6A load shows a bandwidth of 104kHz and phase margin of 54 degrees Rev 8.0 PD-97506 IR3856WMPbF 27 ...
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Simultaneous Tracking at Power Up and Power Down Vin=12V, Vo=1.8V, Io=6A, Room Temperature, No Air Flow 3.3V R 4.02K s1 2..55K R s2 Fig. 25: Simultaneous Tracking a 3.3V input at power-up and shut-down with 6A load Vo2 ...
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Layout Considerations 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. Make all the connections for components in the top ...
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Fig. 26b. IRDC3856 demoboard layout considerations – Bottom Layer Analog Ground plane Single point connection between AGND & PGND, should be close to the SupIRBuck, kept away from noise sources. Fig. 26c. IRDC3856 demoboard layout considerations – Mid Layer 1 ...
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PCB Metal and Components Placement Rev 8.0 PD-97506 IR3856WMPbF 31 ...
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Solder Resist Rev 8.0 PD-97506 IR3856WMPbF 32 ...
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Stencil Design Rev 8.0 PD-97506 IR3856WMPbF 33 ...
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IR WORLD HEADQUARTERS: This product has been designed and qualified for the Consumer market Rev 8.0 IR3856WMPbF 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 ...