iru3038 International Rectifier Corp., iru3038 Datasheet

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... IRU3038 0.1uF Rt Comp C7 2200pF R3 33K Figure 1 - Typical application of IRU3038 when Vtt tracks the V PACKAGE ORDER INFORMATION T (° Rev. 2.0 09/12/02 SYNCHRONOUS PWM CONTROLLER DESCRIPTION The IRU3038 controller IC is designed to provide a low cost synchronous Buck regulator for voltage tracking applications such DDR memory and general purpose on-board converter ...

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... IRU3038 ABSOLUTE MAXIMUM RATINGS Vcc Supply Voltage .................................................. 25V Vc Supply Voltage ..................................................... 30V (not rated for inductive load) Storage Temperature Range ...................................... -65°C To 150°C Operating Junction Temperature Range ..................... PACKAGE INFORMATION 14-PIN PLASTIC TSSOP ( Comp REF 11 Vcc 4 Rt ...

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... The converter can be shutdown by pulling this pin below 0.5V. Rev. 2.0 09/12/02 TEST CONDITION SS=3V, Fb=1V SS=0V, Fb=1V m Rt=Open Rt=Gnd C =1500pF LOAD r C =1500pF f LOAD Fb=1V, Freq=200KHz Fb=1.5V www.irf.com IRU3038 MIN TYP MAX UNITS -0 -64 1.5 V 0.8 600 mmho 750 450 200 220 KHz 180 400 ...

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... Short-Circuit Protection ). The outputs are protected against the short-circuit. The P IRU3038 protects the circuit for shorted output by sens- ing the output voltage (through the external resistor di- vider). The IRU3038 shuts down the PWM signals, when the output voltage drops below 0.6V. The IRU3038 also protects the output from over-voltaging when the control FET is shorted ...

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... OUT 1.25V P REF When an external resistor divider is connected to the output as shown in Figure 3. IRU3038 V Fb REF V P Figure 3 - Typical application of the IRU3038 for programming the output voltage. Equation (1) can be rewritten as OUT Choose R = 1KV 5 This will result to R ...

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... This will result to a ripple approximately 26.5% of output current. Power MOSFET Selection The IRU3038 uses two N-Channel MOSFETs. The se- lections criteria to meet power transfer requirements is based on maximum drain-source voltage (V source drive voltage (V ...

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... SW(TOTAL) Rev. 2.0 09/12/02 Feedback Compensation The IRU3038 is a voltage mode controller; the control loop is a single voltage feedback path including error amplifier and error comparator. To achieve fast transient response and accurate output regulation, a compensa- tion circuit is necessary. The goal of the compensation ...

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... IRU3038 Note that this method requires that the output capacitor should have enough ESR to satisfy stability requirements. In general, the output capacitor’s ESR generates a zero typically at 5KHz to 50KHz which is essential for an acceptable phase margin. The ESR zero of the output capacitor expressed as fol- ...

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... Place third pole at the half of the switching frequency 3(1+ > 50pF 12 If not, change R 5) Place R in equation (15) and calculate www.irf.com IRU3038 2p3R 3(R ...

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... Vc 24V) at 400KHz switching frequency and maxi- mum gate loads. This IC's power dissipation results to an excessive tem- perature rise and should be considered when using IRU3038 for such an application. 10 Layout Consideration The layout is very important when designing high fre- quency switching converters. Layout will affect noise pickup and can cause a good design to perform with less than expected results ...

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... Figure 9 - Transconductance of IRU3038. IRU3038 Rise Time / Fall Time C = 1500pF L -40°C -25°C 0°C +25°C +50°C +75°C Rise Time Fall time Figure 10 - Rise and fall time of IRU3038. www.irf.com IRU3038 IRU3038 Transconductance (GM) -25°C 0°C +25°C +50°C +75°C +100°C Transconductance (GM) +100°C 11 ...

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... Vcc Vc V REF HDrv IRU3038 C8 LDrv 0.1uF PGnd Rt Fb Comp C9 Gnd 1800pF R4 26.1K Figure 11 - Typical application of IRU3038 in an on-board DC-DC converter 450 400 350 300 250 200 150 BAT54S C2 2x 10TPB100ML, C5 100uF, 55m 0.1uF Q1 IRF7460 D05022P-103, 3.3uH, 10A Q2 IRF7460 R6 ...

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... IRU3038 C12 LDrv 0.15uF PGnd Rt Comp C14 Fb 2200pF Gnd R6 33K Figure 13 - Typical application of IRU3038 for DDR memory when the termination voltage tracks the core voltage generated by IRU3037. Rev. 2.0 09/12/02 12V C2 C3 1uF 10TPB100M, V 100uF, 55m Q1 1/2 of IRF7313 L2 D03316P-103, 10uH, 3.9A Q1 1/2 of IRF7313 ...

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... R13 R2 Open Short V V DDQ P R1 IRU3038 SS Open C8 0.1uF Rt Comp C15 Gnd 1800pF R9 26.1K Figure 14 - Demo-board application of IRU3038. Application Parts List Ref Desig Description Q1, Q2 MOSFET 20V, 10mV, 12A U1 Controller Synchronous PWM D1 Diode Fast Switching, Schottky L1 Inductor 1mH, 10A L2 Inductor 3.3mH, 12A C1 ...

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... TYPICAL PERFORMANCE CHARACTERISTICS Output Current (A) Figure 15 - Efficiency for IRU3038 Evaluation Board. V =5V, V =2.5V IN OUT Vss V OUT I OUT Figure 17 - Shutdoown the output by pulling down the soft-start Figure 19 - Transient response @ I Rev. 2.0 09/12/ Figure 16 - Start-up time @ I Figure ...

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... IRU3038 A 1.0 DIA E PIN NUMBER NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. 16 (F) TSSOP Package 14-Pin SYMBOL 14-PIN DESIG MIN NOM MAX 0.65 BSC A B 4.30 4.40 4.50 C 6.40 BSC D 0.19 --- 0.30 E 1.00 F 1.00 G 4.90 5.00 5.10 H --- --- 1.10 J 0.85 0.90 0.95 K 0.05 --- 0.15 L 128 REF M 128 REF N 08 --- 88 O 1.00 REF P 0.50 0.60 0.75 Q 0.20 R 0.09 --- --- R1 0.09 --- --- www ...

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... Surface Mount, Narrow Body PIN NO. 1 NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. Rev. 2.0 09/12/02 (S) SOIC Package E DETAIL-A D 0.386 0.015 x 458 14-PIN SYMBOL MIN MAX A 8.56 8.74 B 1.27 BSC 0.51 REF C D 0.36 0.46 E 3.81 3.99 F 1.52 1.72 G 0.10 0. BSC I 0.19 0.25 J 5.80 6. 0.41 1.27 T 1.37 1.57 www.irf.com IRU3038 H L DETAIL ...

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... IRU3038 PACKAGE SHIPMENT METHOD PKG PACKAGE DESIG DESCRIPTION F TSSOP Plastic S SOIC, Narrow Body 1 1 Feed Direction Figure A IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 18 PIN PARTS COUNT PER TUBE 14 100 Visit us at www.irf.com for sales contact information Data and specifications subject to change without notice ...