ir3621 International Rectifier Corp., ir3621 Datasheet
ir3621
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ir3621 Summary of contents
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... Comp1 LDrv1 PGnd1 IR3621 Comp2 SS1 / SD HDrv2 SS2 / SD OCSet2 Gnd LDrv2 PGnd2 Current share, single output configuration 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 ...
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... IR3621 & (PbF) ABSOLUTE MAXIMUM RATINGS Vcc, V Supply Voltage ........................................... CL VcH1 and VcH2 Supply Voltage ................................ -0.5V To 25V PGOOD.................................................................... Storage Temperature Range ...................................... -55°C To 150°C Junction Temperature Range ..................................... -40°C To 150°C ESD Classification ................................................... Caution: Stresses above those listed in “Absolute Maximum Rating” may cause permanent damage to the device. These are stress ratings only and function of the device at these or any other conditions beyond those indicated in the operational sections of the specifica- tions is not implied. Exposure to “ ...
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... V OS(ERR) 1,2 REF VP2 Note2 Freq Rt to 30.9K (SET) V Note2 RAMP Dmin Fb=1V F =300kHz, Note2 SW Dmax Fb=0.6V, F =200kHz SW 20% above free running freq Sync(H) Sync(L) www.irf.com IR3621 & (PbF) =12V and 0°C<T <125° MIN TYP MAX UNITS 0. -1.35 +1.35 % -2.5 +1.35 % -1.35 +1.35 % -1.65 +1. ...
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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 Shutdown Hysteresis ...
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... In inde- pendent 2-channel mode it is connected to V the resistor divider to set the output voltage. Reference Voltage. The drive capability of this pin is about 2 A. Analog ground for internal reference and control circuitry. No Connect www.irf.com IR3621 & (PbF) pin when Fb2 is connected to REF 5 ...
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... Reset Dom Two Phase Oscillator Set2 Ramp2 Reset Dom S SS1 PWM Comp2 Q SS2 R Mode 0.3V POR SS2 OVP PGood / OVP HDrv OFF / LDrv ON Regulator Figure 3 - IR3621Block Diagram www.irf.com S POR PBias1 Q R VcH1 HDrv1 V CL SS1 LDrv1 3uA PBias1 PGnd1 OCSet1 20uA VcH2 HDrv2 ...
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... Independent Mode In this mode the IR3621 provides control to two indepen- dent output power supplies with either common or differ- ent input voltages. The output voltage of each individual ...
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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 controlling the rise time of each output through selection of different value soft-start capacitors ...
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... This results in much smaller input capacitor's RMS current and reduces the input capacitor quantity. Over-Current Protection The IR3621 can provide two different schemes for Over- Current Protection (OCP). When the Hiccup pin is pulled high, the OCP will operate in hiccup mode. In this mode, ...
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... FET drivers turn on, thus crowbaring the out- puts. Reset is performed by recycling Vcc. Error Amplifier The IR3621 is a voltage mode controller. The error ampli- fiers are of transconductance type. In independent mode, each amplifier closes the loop around its own output volt- age ...
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... OUT 0.8V P2 REF When an external resistor divider is connected to the output as shown in Figure 11. IR3621 V Fb REF V P2 Figure 11 - Typical application of the IR3621 for pro- gramming the output voltage. Equation (4) can be rewritten as OUT × Will result to ...
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... D = The capacitors value must be high enough to absorb the V IN inductor's ripple current. ---(7) Power MOSFET Selection The IR3621 uses four N-Channel MOSFETs. The selec- tion criteria to meet power transfer requirements is based on maximum drain-source voltage (V drive voltage (V tance R and thermal management. DS(ON) The both control and synchronous MOSFETs must have ...
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... This results to =6.75KΩ SET 1 6 This resistor must be placed close to the IC, place a small ceramic capacitor from this pin to ground for noise rejection purposes. www.irf.com IR3621 & (PbF × × I ---(9) LOAD T t ...
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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 circuit is necessary. The goal of the compensation net- ...
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... E/A output. It may exceed its source/sink output current capability, so that the ampli- fier will not be able to swing its output voltage over the necessary range. S The compensation network has three poles and two ze- ros and they are expressed as follows: www.irf.com IR3621 & (PbF) V OUT ...
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... IR3621 & (PbF ×C 2π× × × 2π× ×C 2π× ×(R 2π× Cross Over Frequency ×C × × 2π×Lo×Co ...
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... These two grounds must be connected together on the PC board 1 layout at a single point 300 400 500 600 Freq (kHz) www.irf.com IR3621 & (PbF) 100pF 1000pF 1800pF 3300pF 700 17 ...
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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 VcH2 VcH1 V CL OUT3 HDrv1 Q2 Vcc R1 OCSet1 LDrv1 Q3 Hiccup PGnd1 V P2 Sync ...
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... OUT3 HDrv1 Q2 R1 OCSet1 LDrv1 Q3 PGnd1 V P2 REF U1 V SEN1 IR3621 V SEN1 V SEN2 Fb1 Fb2 HDrv2 Q4 R6 OCSet2 PGood LDrv2 Q5 SS1 / SD PGnd2 SS2 / SD Gnd 12V to 1.8V @ 30A output www.irf.com IR3621 & (PbF) D1 C11 C14 L3 R5 C15 R7 C16 C17 C18 L4 1.8V @ 30A 19 ...
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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 Charge Current vs. Temperature -50 - Temperature (C) 20 0.8060 0.8040 0.8020 0.8000 0.7980 0.7960 ...
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... LO Drive Rise/Fall Time vs. Temperature Dr2 Rise HI Dr2 Fall 100 125 -50 -25 www.irf.com IR3621 & (PbF) (300kHz, 1500pF) ICC ICH1+ICH2 ICL 100 125 Temperature (C) H_to_L_1 H_to_L_2 L_to_H_1 L_to_H_2 100 Temperature (C) ...
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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 - Start up waveforms Ch1: Vin, Ch2: Vout3, Ch3: Vref 22 =1.8V, I =0-10A, Fs=400kHz, T ...
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... Figure 27 - Gate waveforms with 180 out of phase Ch1: Hdrv1, Ch2: Hdrv2 =1.8V, I =0-10A, Fs=400kHz, Ta=Room Temp, No Air Flow OUT2 OUT2 Ch1: Vin, Ch2: SS2, Ch3: Vo2, Ch4: PGood o Figure 28 - 2.5V Waveforms Ch1: Hdrv1, Ch2: Ldrv1, Ch3: Lx1, Ch4: Inductor Current www.irf.com IR3621 & (PbF) Figure 26 - 1.8V output 23 ...
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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 shorted Ch1: Vo2, Ch2: SS1, Ch3: Inductor Current 24 =1.8V, I =0-10A, Fs=400kHz, Ta=Room Temp, No Air Flow ...
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... Ch1: SS1, Ch2: Hdrv1, Ch3: Ldrv1, Ch4:Vo2 Ch1: External Clock, Ch2: Hdrv1, Ch3: Hdrv2 =1.8V, I =0-10A, Fs=400kHz, Ta=Room Temp, No Air Flow OUT2 OUT2 Figure 34 - SS2 pin shorted to Gnd Ch1: SS2, Ch2: Hdrv2, Ch3: Ldrv2, Ch4:Vo1 Figure 35 - External Synchronization www.irf.com IR3621 & (PbF) 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 36 - Load Transient Respons for Vo1 (Io=0 to 10A) Ch1: Vo1, Ch4:Io1 Figure 38 - Load Transient Respons for Vo2 (Io=0 to 10A) Ch1: Vo2, Ch4: Io2 26 =1.8V, I =0-10A, Fs=400kHz, Ta=Room Temp, No Air Flow ...
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... Figure 40 - Efficiency for 2.5V and 1.8V outputs at room temperature and no air flow. Efficiency was measured when the other output was operating at no load. =1.8V, I =0-10A, Fs=400kHz, Ta=Room Temp, No Air Flow OUT2 OUT2 12V to 2.5V and 1. Io(A) www.irf.com IR3621 & (PbF) 2.5V 1. ...
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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. A1 32-PIN 5x5 ...
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... MAX 4.50 TAPE & REEL ORIENTATION 0.30 9.80 1 1.10 0.95 0.15 Figure A : Feed Direction 8 0.75 --- --- Visit us at www.irf.com for sales contact information Data and specifications subject to change without notice. 11/29/2007 www.irf.com IR3621 & (PbF DETAIL A DETAIL TAC Fax: (310) 252-7903 29 ...