IR3841WMPBF International Rectifier, IR3841WMPBF Datasheet
IR3841WMPBF
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IR3841WMPBF Summary of contents
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... Seq Vcc PGood PGood Rt SS/ SD Fig. 1. Typical application diagram Rev 5.0 IR3841WMPbF HIGHLY EFFICIENT Description The IR3841W SupIRBuck fully integrated and highly efficient DC/DC synchronous Buck regulator. The MOSFETs co- packaged with the on-chip PWM controller make IR3841W a space-efficient solution, providing accurate power delivery for low output voltage applications ...
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... DESIGNATOR M M Rev 5 Gnd Seq FB COMP Gnd Rt SS OCSet PACKAGE PIN COUNT DESCRIPTION IR3841WMTRPbF 15 IR3841WMTR1PbF 15 IR3841WMPbF www.DataSheet4U.com and -40 C PGnd θ θ PCB - V CC PGood PARTS PER REEL 4000 ...
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... Block Diagram Fig. 2. Simplified block diagram of the IR3841W Rev 5.0 IR3841WMPbF www.DataSheet4U.com 3 ...
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... SW. Enable pin to turn on and off the device. Use two external resistors to 14 Enable set the turn on threshold (see Enable section). Connect this pin to Vcc not used. 15 Gnd Signal ground for internal reference and control circuitry. Rev 5.0 IR3841WMPbF Description www.DataSheet4U.com 4 ...
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... C<Tj<125 -40 C<Tj<125 C, Note3 SS=0V, No Switching, Enable low SS=3V, Vcc=5V, Fs=500kHz Enable high Vcc Rising Trip Level Vcc Falling Trip Level Supply ramping up Supply ramping down Enable=3.3V IR3841WMPbF www.DataSheet4U.com Max Units 16 5.5 V 5.5 0.9*Vin 8 A 1650 kHz o 125 C =12V C<T < 125 o C ...
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... Vfb-Vseq, -10 Vseq=0. 0.40 8 Note4 7 Note4 20 Note4 100 Vcc=4.5V 3.4 Note4 0 Source 14 2.7 Fs=250kHz 20.8 Fs=500kHz 43 Fs=1500kHz 136 Note4 -10 I(Boot)=30mA 180 Note4 5 IR3841WMPbF www.DataSheet4U.com =12V C<T < 125 TYP MAX Units 0.7 0.735 V 250 275 500 550 kHz 1500 1650 +10 % 1.8 Vp-p 0 130 200 ...
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... C. Test Condition Min Note4 Note4 Fb Rising 0.770 Fb Rising Fb Falling 0.560 Fb Falling Relative to charge voltage, SS rising 2 Note4 260 I =-5mA PGood SW=0V, Enable=0V SW=0V,Enable=high,SS=3V,Vseq=0V , Note4 IR3841WMPbF www.DataSheet4U.com =12V C<T < 125 TYP MAX Units 140 0.805 0.840 V 256/Fs s 0.595 0.630 ...
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... Vo (V) 0.7 0.8 0.9 1.0 1.1 1.2 1.5 1.8 2.5 3.3 5 0.9V 1.0V 2.1 1.9 1.7 1.5 1.3 1.1 0.9 0.7 0.5 0.3 0 0.9V 1.0V Rev 5.0 =600kHz, Room Temperature, No Air Flow s L (uH) P/N DCR (mOhm) 0.4 59PR9875N 0.29 0.4 59PR9875N 0.29 0.4 59PR9875N 0.29 0.5 59PR9876N 0.29 0.5 59PR9876N 0.29 0.6 MPL104-0R6 1.50 0.9 MPC1040LR88 2.30 0.9 MPC1040LR88 2.30 1.0 MPL105-1R0IR 2.30 1.2 MPL105-1R0IR 2.30 1.5 MPL105-1R0IR 2. Load Current (A) 1.1V 1.2V 1.5V 1.8V 2. Load Current (A) 1.1V 1.2V 1.5V 1.8V 2.5V IR3841WMPbF www.DataSheet4U.com 7 8 3.3V 5. 3.3V 5.0V 8 ...
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... Typical Efficiency and Power Loss Curves Vin=5V, Vcc=5V, Io=1A-8A For all the output voltages, L=0.51uH (DCR=0.29 mΩ, P/N: 59PR9876N 1.0 1.5 2.0 2.5 3.0 0.7V 0.75V 0.9V 1.7 1.5 1.3 1.1 0.9 0.7 0.5 0.3 0.1 1.0 1.5 2.0 2.5 0.7V 0.75V 0.9V Rev 5.0 =600kHz, Room Temperature, No Air Flow 3.5 4.0 4.5 5.0 5.5 Load Current (A) 1.0V 1.1V 1.2V 1.5V 3.0 3.5 4.0 4.5 5.0 5.5 Load Current (A) 1.0V 1.1V 1.2V 1.5V IR3841WMPbF www.DataSheet4U.com 6.0 6.5 7.0 7.5 8.0 1.8V 2.5V 3.3V 6.0 6.5 7.0 7.5 8.0 1.8V 2.5V 3.3V 9 ...
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... IR3841WMPbF www.DataSheet4U.com C - 125 C) F =500 kHz Ic(Dyn 100 120 o Temp[ C] IOCSET(500kHz 100 120 o Temp[ C] Vcc(UVLO) Stop 100 120 ...
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... Rdson of MOSFETs Over Temperature at Vcc= -40 -20 0 Rev 5 Temperature [°C] Sync-FET Ctrl-FET IR3841WMPbF www.DataSheet4U.com 100 120 140 11 ...
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... MOSFETs Fig. 3a. Normal Start up, Device turns on efficiency when the Bus voltage reaches 10.2V Figure 3b. shows the recommended start-up sequence for the non-sequenced operation of IR3841W, when Enable is used as a logic input. Fig. 3b. Recommended startup sequence, Non-Sequenced operation IR3841WMPbF www.DataSheet4U.com . This is desirable particularly in 12 ...
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... MOSFET is internally programmed. Figure 5 shows a series of 32, 16, 8 startup pulses. Fig. 4. Pre-Bias startup Rev 5.0 IR3841WMPbF Fig. 5. Pre-Bias startup pulses Soft-Start The IR3841W has a programmable soft-start to control the output voltage rise and to limit the current surge at the start-up. To ensure correct ...
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... After every soft start cycle, the converter stays in this mode until the overload or short circuit is removed. The OCP circuit starts sampling current typically OCSet 160 ns after the low gate drive rises to about 3V. . This delay functions to filter out switching noise. t IR3841WMPbF www.DataSheet4U.com 1400 = ) .......... .......... .......... .....( ) 2 Ω ...
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... PGood goes high after the SS voltage reaches 2.1V if the Fb voltage is within the PGood comparator window. Fig. 9a. and Fig 9.b. also show a 256 cycle delay between the Fb voltage entering within the thresholds defined by the PGood window and PGood going high. IR3841WMPbF www.DataSheet4U.com Enable Vin Boot Vo(slave) ...
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... TIMING DIAGRAM OF PGOOD FUNCTION Fig.9a IR3841W Non-Tracking Operation (Seq=Vcc) Fig.9b IR3841W Tracking Operation Rev 5.0 IR3841WMPbF www.DataSheet4U.com 16 ...
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... Fig 10. shows a plot of the maximum duty ratio v/s the switching frequency, with 250 ns off-time 250 450 Fig. 10. Maximum duty cycle v/s switching frequency V/s IR3841WMPbF www.DataSheet4U.com Duty Cycle 650 850 1050 1250 1450 1650 S w itching Frequency ( ...
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... V the bootstrap capacitor C6 is approximately given as ≅ When the upper MOSFET turns on in the next cycle, the capacitor node connected to SW rises .......... .....(7) to the bus voltage appropriately chosen, IR3841WMPbF www.DataSheet4U.com ⎞ V ref ⎟ .......... .......... .......... .... (8) ⎟ − ⎠ ...
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... Turn Duty cycle If Δi ≈ 35%(I ), then the output inductor is o calculated to be 0.91μH. Select L=1 μH. The MPL105-1R0 from Delta provides a compact, low profile inductor suitable for this application. . IR3841WMPbF www.DataSheet4U.com Δ The optimum ripple current can be 1 Δ = ∗ t ...
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... Local feedback with Type II compensation is shown in Fig. 14. This method requires that the output capacitor should have enough ESR to generate a zero typically at 5kHz to 50kHz, which is essential for an acceptable phase margin and to satisfy stability requirements ESR IR3841WMPbF www.DataSheet4U.com 1 .......... .......... .......... .. (16) π ∗ ...
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... III compensation network. The typically used compensation network for voltage-mode controller is shown in figure 15. Again, the transfer function is given by replacing Z ....... (21) the transfer function can be expressed as: = − IR3841WMPbF www.DataSheet4U.com 1 .......... .......... .......... ....... (22 .......... .......... .......... ...(23 POLE ...
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... These result to: =18.76 kHz F LC =4.4 MHz F ESR /2=300 kHz of the F s Select crossover frequency: F Since F <F LC place the pole and zeros. IR3841WMPbF www.DataSheet4U.com Output Output ESR ESR o o Capacitor Capacitor Electrolytic Electrolytic F F <F <F <F < ...
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... PGood pin, when the = : C 150 pF output voltage is not in regulation, to less than 5 3 mA. A typical value used is 10kΩ. = Ω 130 Ω 2. IR3841WMPbF www.DataSheet4U.com ) from the SW pin OCSET has a positive temperature ∗ OCSet OCSet = .......... .......... ... (32 ...
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... 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, 8A, PQFN 5x6mm International Rectifier IR3841WMPbF IR3841WMPbF www.DataSheet4U.com Part Number EEV-FK1E331P C3216X5R1E106M ECJ-1VB1E104K MPL105-1R0 ECJ-2FB0J226ML MCR03EZPFX4992 MCR03EZPFX7501 MCR03EZPFX2372 ...
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... Bias, 0A Load out 3 Fig. 21: Inductor node at 8A load Ch :LX 3 Rev 5.0 Fig. 18: Start Load Fig. 20: Output Voltage Ripple, 8A load Ch SS Fig. 22: Short (Hiccup) Recovery Ch IR3841WMPbF www.DataSheet4U.com : out PGood : V 2 out : out 3 ss ...
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... TYPICAL OPERATING WAVEFORMS Vin=12V, Vcc=5V, Vo=1.8V, Io=4-8A, Room Temperature, No Air Flow Fig. 23: Transient Response step 2.5A/us Rev 5.0 IR3841WMPbF out 4 out www.DataSheet4U.com 26 ...
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... TYPICAL OPERATING WAVEFORMS Vin=12V, Vcc=5V, Vo=1.8V, Io=8A, Room Temperature, No Air Flow Fig. 24: Bode Plot at 8A load shows a bandwidth of 91kHz and phase margin of 55 degrees Rev 5.0 IR3841WMPbF www.DataSheet4U.com 27 ...
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... Simultaneous Tracking at Power Up and Power Down Vin=12V, Vo=1.8V, Io=8A, 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 Rev 5.0 V OUT IR3841W IR3624 R 8 Seq Ch2: Vout Ch3:SS Ch4: SEQ IR3841WMPbF www.DataSheet4U.com 4.02K 2.55K 28 ...
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... Figure 26 illustrates the feedback implementation of the layout guidelines outlined above, on the IRDC3841W 4 layer demoboard. PGnd Vin Vin PGnd Vout Vout IR3841WMPbF www.DataSheet4U.com PGnd PGnd Vout Vout Enough copper & minimum length ground path between Input and Output All bypass caps ...
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... AGND & PGND, should be close to the SupIRBuck, kept away from noise sources. Fig.26c. IRDC3841W demoboard layout considerations – Mid Layer 1 Fig.26d. IRDC3841W demoboard layout considerations – Mid Layer 2 Rev 5.0 IR3841WMPbF www.DataSheet4U.com PGnd Power Vin Ground Plane AGnd Use separate traces for connecting Boot ...
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... Pad lands (the 4 big pads other than the 11 IC pins) length and width should be equal to maximum part pad length and width. However, the minimum metal to metal spacing should be no less than 0.17mm for 2 oz. Copper; no less than 0.1mm for 1 oz. Copper and no less than 0.23mm for 3 oz. Copper. Rev 5.0 IR3841WMPbF www.DataSheet4U.com 31 ...
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... Ensure that the solder resist in-between the lead lands and the pad land is ≥ 0.15mm due to the high aspect ratio of the solder resist strip separating the lead lands from the pad land. Rev 5.0 IR3841WMPbF www.DataSheet4U.com 32 ...
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... The maximum length and width of the land pad stencil aperture should be equal to the solder resist opening minus an annular 0.2mm pull back to decrease the incidence of shorting the center land to the lead lands when the part is pushed into the solder paste. Rev 5.0 IR3841WMPbF www.DataSheet4U.com 33 ...
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... IR WORLD HEADQUARTERS: This product has been designed and qualified for the Consumer market Rev 5.0 IR3841WMPbF BOTTOM VIEW 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 without notice. 01/09 www ...