IR3621M International Rectifier, IR3621M Datasheet
IR3621M
Specifications of IR3621M
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IR3621M Summary of contents
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... Figure 1 - Typical application of IR3621 in current share single output and 2-independent output voltage configuration PKG PART LEADFREE DESIG NUMBER PART NUMBER M IR3621M IR3621MPbF M IR3621MTR IR3621MTRPbF F IR3621F IR3621FPbF F IR3621FTR IR3621FTRPbF DESCRIPTION The IR3621 IC combines a dual synchronous buck control- ler and drivers, providing a cost-effective, high performance and flexible solution. The IR3621 operates in 2-Phase mode to produce either 2-independent output voltages or current share single output for high current application ...
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... MLPQ 5mmx5mm ( SEN2 3 Fb2 4 Comp2 SS2/SD2 5 OCSet2 6 VCH2 7 HDrv2 8 9 Exposed pad on underside is connected to a copper pad through vias for 4-layer PCB board design. www.irf.com IR3621M & IR3621MPbF Hiccup 23 Sync V 22 SEN1 21 Fb1 Pad Comp1 20 19 SS1/SD1 18 OCSet1 17 ...
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ELECTRICAL SPECIFICATIONS Unless otherwise specified, these specifications apply over Vcc=12V, VcH1=VcH2=V PARAMETER SYMBOL Output Voltage Accuracy Feedback Voltage Accuracy UVLO Section UVLO Threshold - Vcc UVLO Hysteresis - Vcc UVLO Threshold - VcH1,2 UVLO UVLO Hysteresis - VcH1,2 Supply Current ...
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IR3621 & (PbF) PARAMETER V Internal Regulator OUT3 Output Voltage Output Current Protection Section OVP Trip Threshold OVP Fault Prop Delay OVP OCSET Current Hiccup Duty Cycle Hiccup High Level Threshold Hiccup Low Level Threshold Thermal Shutdown Trip Point Thermal ...
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PIN DESCRIPTIONS TSSOP MLPQ PIN SYMBOL 1 PGood 29 2 Vcc OUT3 5, 2,22 SEN2 SEN1 6,22 Fb2,Fb1 3,21 7,21 Comp2, Comp1 4,20 8 SS2 / SS1 ...
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IR3621 & (PbF) BLOCK DIAGRAM Vcc 28uA 28uA 64uA Max SS2 / SD 64uA SS1 / SD POR Error Amp1 0.8V Fb1 Comp1 Rt Sync 0.8V V REF Error Amp2 V P2 Fb2 Comp2 V SEN1 V SEN2 Gnd 6 ...
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FUNCTIONAL DESCRIPTION Introduction The IR3621 is a versatile device for high performance buck converters. It consists of two synchronous buck controllers which can be operated either in two indepen- dent mode or in current share mode. The timing of the ...
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IR3621 & (PbF) Dual Soft-Start The IR3621 has programmable soft-start to control the output voltage rise and limit the inrush current during start-up. It provides a separate Soft-Start function for each outputs. This will enable to sequence the outputs by ...
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For a given start up time, the soft-start capacitor can be calculated by: C 28µA×T SS START The soft-start is part of the Over Current Protection scheme, during the overload or short circuit condition the external soft start capacitors will ...
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IR3621 & (PbF) Frequency Synchronization The IR3621 is capable of accepting an external digital synchronization signal. Synchronization will be enabled by the rising edge at an external clock. Per-channel switch- ing frequency is set by external resistor (Rt). The free ...
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APPLICATION INFORMATION Design Example: The following example is a typical application for the IR3621, the schematic is Figure19 on page18 12V 2.5V @ 10A OUT(2.5V 1.8V @ 10A OUT(1.8V) ∆V = Output voltage ...
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IR3621 & (PbF) Input Capacitor Selection The 180 0 out of phase will reduce the RMS value of the ripple current seen by input capacitors. This reduces numbers of input capacitors. The input capacitors must be selected that can handle ...
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The gate drive requirement is almost the same for both MOSFETs. Logic-level transistors can be used and cau- tion should be taken with devices at very low V vent undesired turn-on of the complementary MOSFET, which results in a shoot-through. ...
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IR3621 & (PbF) Feedback Compensation The IR3621 is a voltage mode controller; the control loop is a single voltage feedback path including error ampli- fier and error comparator. To achieve fast transient re- sponse and accurate output regulation, a compensation ...
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OSC ESR 5 9 × × Where Maximum Input Voltage Oscillator Ramp Voltage OSC F = Crossover Frequency ...
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IR3621 & (PbF ×C 2π× × × 2π× ×C 2π× ...
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Select a zero crossover frequency for control loop (F 1.25 times larger than zero crossover frequency for volt- age loop ( 1.25% ×R ×R × H(Fo 2π×Fo×L From ...
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IR3621 & (PbF) TYPICAL APPLICATION 12V PGood C10 C15 Figure 19 - Typical application of IR3621. 12V input and two independent outputs using type 2 compensation. 18 C12 VcH2 C13 V ...
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TYPICAL APPLICATION 12V Vcc C5 Hiccup Sync Comp1 R4 C9 Comp2 PGood C10 Figure 20 - 2-phase operation with inductor current sensing using type 2 compensation. C12 C13 VcH1 V VcH2 CL ...
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IR3621 & (PbF) TYPICAL OPERATING CHARACTERISTICS Vfb1 vs. Temperature 0.8060 0.8040 0.8020 0.8000 0.7980 0.7960 0.7940 - Temperature [C] VOUT3 vs. Temperature 6.24 6.22 6.2 6.18 6.16 6.14 6.12 6.1 -50 - Temperature (C) SS ...
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TYPICAL OPERATING CHARACTERISTICS Static Supply Current vs. Temperature 30 25 ICC ICH1+ICH2 -50 - Temperature (C) IOCSet vs. Temperature -50 -25 ...
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IR3621 & (PbF) TYPICAL OPERATING WAVEFORMS Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Unless otherwise specified. Figure 21 - Start up waveforms for 2.5V output Ch1: Vin, Ch2: Vout3, Ch3: SS1, Ch4:Vo1 (2.5V) Figure 23 ...
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TYPICAL OPERATING WAVEFORMS Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Unless otherwise specified. Figure 25 - 2.5V output Ch1: Vin, Ch2: SS1, Ch3: Vo1, Ch4: PGood Figure 27 - Gate waveforms with 180 out of ...
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IR3621 & (PbF) TYPICAL OPERATING WAVEFORMS Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Unless otherwise specified. Figure 29 - 2.5V Waveforms Ch1: Hdrv2, Ch2: Ldrv2, Ch3: Lx2, Ch4: Inductor Current Figure 31 - 2.5V output ...
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TYPICAL OPERATING WAVEFORMS Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Unless otherwise specified. Figure 33 - SS1 pin shorted to Gnd Ch1: SS1, Ch2: Hdrv1, Ch3: Ldrv1, Ch4:Vo2 Ch1: External Clock, Ch2: Hdrv1, Ch3: Hdrv2 ...
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IR3621 & (PbF) TYPICAL OPERATING WAVEFORMS Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Unless otherwise specified. Figure 36 - Load Transient Respons for Vo1 (Io=0 to 10A) Ch1: Vo1, Ch4:Io1 Figure 38 - Load Transient ...
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TYPICAL PERFORMANCE CURVES Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Unless otherwise specified Figure 40 - Efficiency for 2.5V and 1.8V outputs ...
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... IR3621 & (PbF) (IR3621M & IR3621MPbF) MLPQ 5x5 Package D D/2 PIN 1 MARK AREA (See Note1) TOP VIEW SIDE VIEW 28 32-Pin E/2 E BOTTOM VIEW Note 1: Details of pin #1 are optional, but must be located within the zone indicated. A The identifier may be molded, or marked A3 features. ...
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TSSOP Package A 1.0 DIA E PIN NUMBER 28-PIN SYMBOL MIN NOM DESIG 0.65 BSC A 4.30 4. 6.40 BSC 0.19 --- D 1.00 E 1.00 F 9.60 9.70 G --- --- H 0.85 ...