iru3072 International Rectifier Corp., iru3072 Datasheet
iru3072
Related parts for iru3072
iru3072 Summary of contents
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... Rev. 1.0 3/25/04 DESCRIPTION The IRU3072 controller IC is designed to provide a low cost synchronous Buck regulator for on-board converter for multi-output applications. The outputs can be programmed as low as 0.8V for low voltage applica- tions. The IRU3072 features dual soft-starts which allows power sequencing between outputs ...
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... IRU3072 ABSOLUTE MAXIMUM RATINGS Vcc and VccLDO Supply Voltage .............................. 25V Vc Supply Voltage .................................................... 25V Storage Temperature Range ...................................... -65°C To 150°C Operating Junction Temperature Range ..................... CAUTION: For all pins, voltage should not be below -0.5V. CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. ...
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... Tf C =3000pF (90% to 10%), LOAD Vcc=12V T Vcc=12V, C =3000pF DB LOAD HDrv falls,LDrv rises Vcc=12V, C =3000pF LOAD LDrv falls, HDrv rises Fb=0.7V, Freq=200KHz MAX Fb=0.9V MIN Drv2, 3 and 4 Note 1 www.irf.com IRU3072 MIN TYP MAX UNITS 0 500 900 1300 mmho 170 200 230 ...
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... IRU3072 PIN# PIN SYMBOL PIN DESCRIPTION 10 Vc This pin is connected to a voltage that must be at least 4V higher than the bus voltage of the switcher (assuming 5V threshold MOSFET) and powers the high side output driver. A minimum of 1mF, high frequency capacitor must be connected from this pin to ground to provide peak drive current capability ...
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... POR Comp 15 25K 0.8V 25K Fb1 14 20uA 3V CS Comp OCSet 11 VccLDO 4 25K Fb2 18 25K Fb3 19 25K Fb4 20 Figure 2 - Simplified block diagram of the IRU3072. Rev. 1.0 3/25/04 Generator 1.27V / 1.2V 64uA 64uA Max Max UVLO 4.2V / 4.0V Vcc 3.5V / 3.3V Vc 2.5V / 2.35V VccLDO Rt Oscillator Ct Enbl Error Comp Error Amp 0.4V 3 64uA 25K=1.6V ...
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... C9 R6 10uF 1K C10 220pF R8 C11 Comp 15nF 3. 46.4K SS1 C13 SSLDO 0.1uF C14 33nF Figure 3 - Typical application of IRU3072. PARTS LIST Ref Desig Description Q1,Q2,Q3 MOSFET 30V, 65mV, 22A Q4,Q5 MOSFET 20V, 10mV, 12A U1 Controller Synchronous PWM D1 Schottky Diode 0.2A, 30V L1 Inductor 1mH Inductor ...
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... In this example Vcc = 5V BUS Vc = VccLDO created by charge pump V = 3.3V SEN33 The IRU3072 will sense all four voltages to ensure all these voltages enter into steady state before the soft- start capacitor is charged up. The operation waveforms are shown in Figure SDB SEN33 Drv2 ...
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... Soft-Start One of the useful features of IRU3072 is that it allows different start-up times for PWM output and LDO output by programming two separate soft-start capacitors. Fig- ure 7 just shows the soft-start for PWM section. ...
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... SS For LDOs: C SSLDO Figure 9 - Soft-start of buck converter (PWM) and LDO. Shutdown The PWM output and LDO output can be turned on and off individually by pulling up and down the correspond- ing soft start capacitors. www.irf.com IRU3072 2V-1V /1V ---(1) and OUT1 5ms START = 33nF, t 2ms START ...
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... Both PWM output and LDO output can be shutdown by pulling the pin V as follows. External Shutdown V / SDB SEN33 Drv2 U1 Fb2 IRU3072 Vcc UVLO VccLDO will not be affected. Soft-Start HDrv OCSet LDrv SS1 SS LDO Figure 12 - External shutdown by www ...
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... MOSFET drivers are off after shutdown. Over Current Protection The IRU3072 over current protection is achieved with a cycle-by-cycle current limit and an output voltage under- voltage lockout scheme. The diagram is shown in Figure 14. It includes an over current comparator and an output voltage UVLO comparator ...
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... OFF (b). Operation at current limit mode. Figure 16 - Cycle-by-Cycle operation when IRU3072 is in over-current limit mode. 12 From Figure 16, first, the high side MOSFET is on for t period and the inductor current increases during this time. Then, the high side MOSFET is off and low side MOSFET is on ...
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... R 3 SET SET DS(ON) Figure 17 - Profile of operation switching frequency versus output current. Rev. 1.0 3/25/04 /20mA ---(3) (a). Normal operation. DS(ON) Shutdown by UVLO I OUT , I S(NOM) O(LIM O(NOM S(NOM) (b). Current limit mode. /2 Figure 18 - Operation waveforms during normal / www.irf.com IRU3072 and current limit mode. 13 ...
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... Output Feedback UVLO Besides the cycle-by-cycle current limit, an output feed- back UVLO is included in the IRU3072 for the output short protection. The diagram is shown in Figure 14. If the output is short or overload, once the voltage at the Fb1 pin is below 0.4V, the output feedback UVLO com- parator will flip and turn off both high side and low side MOSFETs ...
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... Figure 22 - Operation of PWM output and LDO when LDO V is short. OUT2 Figure 23 - Soft-start with output is short to ground. Switching frequency The switching frequency of IRU3072 can be selected by the following figure. 500 450 400 350 300 250 200 150 100 100 Figure 24 - Switching frequency versus resistor Rt ...
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... The switching loss is more difficult to calculate because of the parasitic parameters. In general, the switching loss can be estimated by the following 0.53V 3I 3(tr+tf) OUT tr is the rising time and tf is the falling time. From IRU3072 datasheet: tr=50ns and tf=50ns P = 0.5312V38A3(50ns+50ns)3400KHz SW(HI) P 1.92W SW(HI) The total disspation for the high side switch is: P ...
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... From the datasheet we get V g =1000mmho. The calculated compensation resis- m tor is: Rc1=2p3403131.2531.2/(133123100030.8) Rc1=2.98K Select R8=Rc1=3.3K The compensator capacitor is given as: Cc1 = Cc1 = Select C9=Cc1=15nF www.irf.com IRU3072 of 14mV, then: DS(ON) =6.8KV SET IRU3072 Error Amp Rc1 Comp Cc2 (Optional) 3L3V 3V O OSC OUT 3g 3V ...
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... IRU3072 (Optional) an additional capacitor Cc2 can be adopted, where: Cc2 1/(p3Rc13F ) 220pF S (5) Feedback resistor The output of PWM is determined by 3(R +R )/R OUT REF -1)3R T OUT REF B Where V =0.8V REF R is the top feedback resistor and R T feedback resistor.For 1.2V output, R LDO Regulator Component Selection ...
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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. Figure 27 - Transient response (zoomed). Figure 28 - Transient response (zoomed). www.irf.com IRU3072 19 ...
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... Fb4 OUT4 866 1. C10 100pF R8 C11 Comp 10nF 6. 46.4K SS1 C13 SSLDO 0.1uF C14 Gnd 33nF Figure 29 - IRU3072 typical application with one bus input voltage V 3.3V V SEN33 Q1 Drv2 IRLR2703 R1 V Fb2 OUT2 2.15K 2. Drv3 R3 V OUT3 Fb3 1.24K 1.8V ...
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... Fb4 OUT4 866 1. C10 220pF R8 C11 Comp 15nF 3. 47K SS1 C13 SSLDO 0.1uF C14 33nF Figure 32 - IRU3072 typical application with one bus input voltage V Rev. 1.0 3/25/04 / SDB Vcc C1 1uF VccLDO C3 1uF IRU3072 1uF 0.1uF Q4 HDrv IRF7460 R7 OCSet 4 ...
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... V Fb4 OUT4 866 1. C10 220pF R8 C11 Comp 15nF 3. 47K SS1 C13 SSLDO 0.1uF C14 33nF Figure 33 - IRU3072 typical application with one bus input voltage V 22 R13 1K / SDB Vcc C1 1uF VccLDO 1uF 0.1uF IRU3072 Q4 HDrv IRF7460 R7 OCSet 6.8K Q5 LDrv ...
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... A The identifier may be molded, or marked A3 features. A1 20-PIN 4x4 SYMBOL DESIG MIN NOM MAX A 0.80 0.90 1.00 A1 0.00 0.02 0.05 A3 0.20 REF B 0.18 0.23 0.30 D 4.00 BSC D2 2.00 2.15 2.25 E 4.00 BSC E2 2.00 2.15 2.25 e 0.50 BSC L 0.45 0.55 0.65 R 0.09 --- --- NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. www.irf.com IRU3072 D2 EXPOSED PAD PIN NUMBER ...
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... IRU3072 PACKAGE SHIPMENT METHOD PKG PACKAGE DESIG DESCRIPTION H MLPQ 4x4 IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 24 PIN PARTS COUNT PER TUBE 20 TBD Feed Direction Figure A This product has been designed and qualified for the industrial market. ...