iru3138 International Rectifier Corp., iru3138 Datasheet
iru3138
Related parts for iru3138
iru3138 Summary of contents
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... To 70 Rev. 1.0 01/29/04 SYNCHRONOUS PWM CONTROLLER DESCRIPTION The IRU3138 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. Modern micro processors combined with DDR memory, need high-speed bandwidth data bus which requires a particular bus termination volt- age ...
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... IRU3138 ABSOLUTE MAXIMUM RATINGS V Supply Voltage .................................................. -0.5V - 25V CC V Supply Voltage .................................................... -0.5V - 25V C Storage Temperature Range ...................................... -65°C To 150°C Operating Junction Temperature Range ..................... CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. PACKAGE INFORMATION 14-PIN PLASTIC SOIC NB (S) ...
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... The converter can be shutdown by pulling this pin below 2.8V. Rev. 1.0 01/29/04 TEST CONDITION SS=3V, Fb=1V SS=0V, Fb=1V C =3000pF LOAD C =3000pF LOAD f Fb=0.7V, Freq=200KHz Fb=1.5V pins to this pin for noise free operation. C www.irf.com IRU3138 MIN TYP MAX UNITS 0 1.5 V 0.7 800 mmho 1000 500 ...
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... V REF 3 1.25V 4.25V 3V Vc 20uA 3.5V 64uA Max SS/SD 13 POR Error Amp 25K 25K Comp Figure 2 - Simplified block diagram of the IRU3138 Bias Generator 1.25V 0.25V POR 0.2V Rt Oscillator Error Comp R Reset Dom FbLo Comp 0.4V POR www.irf.com HDrv ...
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... THEORY OF OPERATION Introduction The IRU3138 is a fixed frequency, voltage mode syn- chronous controller and consists of a precision refer- ence voltage, an error amplifier, an internal oscillator, a PWM comparator, 1A peak gate driver, soft-start and shutdown circuits (see Block Diagram). The output volt- age of the synchronous converter is set and controlled by the output of the error amplifier ...
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... The outputs are protected against the short-circuit. The IRU3138 protects the circuit for shorted output by sens- ing the output voltage (through the external resistor di- vider). The IRU3138 turns off both drivers, when the out- put voltage drops below 0.4V. The IRU3138 also protects the output from over-voltaging when the control FET is shorted ...
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... APPLICATION INFORMATION Design Example: The following example is a typical application for IRU3138, the schematic is Figure 13 on page 15 Supply Voltage 1. 12V OUT 12A OUT DV = 50mV OUT (output voltage ripple OUT f = 400KHz S Output Voltage Programming Output voltage is programmed by reference voltage and external voltage divider ...
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... The capacitor value must be high enough to absorb the inductor's ripple current. The larger the value of capaci- tor, the lower will be the output ripple voltage. Power MOSFET Selection The IRU3138 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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... P = 336mW SW(TOTAL) Feedback Compensation The IRU3138 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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... IRU3138 The IRU3138’s error amplifier is a differential-input transconductance amplifier. The output is available for DC gain control or AC phase compensation. The E/A can be compensated with or without the use of local feedback. When operated without local feedback, the transconductance properties of the E/A become evi- dent and can be used to cancel one of the output filter poles ...
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... Compensator Type Type II (PI) Type III (PID) Method A Type III (PID) Method B Table - The compensation type and location of zero Detail information is dicussed in application Note AN- 1043 which can be downloaded from the IR Web-Site. www.irf.com IRU3138 2p3R ...
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... IRU3138 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. Start to place the power components. Make all the con- nections in the top layer with wide, copper filled areas. ...
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... TYPICAL APPLICATION Single Supply 5V Input C3 0.1uF Vcc V REF C8 U1 0.1uF V P IRU3138 SS/SD C8 0.1uF Rt Comp C9 3.3nF C6 Gnd 68pF R4 18K Figure 11 - Typical application of IRU3138 in an on-board DC-DC converter Rev. 1.0 01/29/ BAT54 BAT54S C4 1uF C5 Vc 0.1uF Q1 HDrv IRF7457 D3 BAT54 Q2 LDrv IRF7457 PGnd R6 Fb 3.16K 1K, 1% using a single 5V supply ...
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... IRU3138 C12 0.15uF Rt Comp C14 6800pF Gnd C16 47pF R6 12K Figure 12 - Typical application of IRU3137 for DDR memory when the termination voltage, generated by IRU3138, tracks the core voltage. 14 12V C2 1uF C5 4x 150uF 6TPB150M Vc Q1 HDrv IRF3711S D1 1N4148 Q2 LDrv IRF3711S ...
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... Gnd 12V Vcc Vc C3 1uF REF C2 IRU3138 100pF SS/SD C8 0.1uF Comp C15 Gnd 2.2nF R9 17.8K Figure 13 - Demo-board application of IRU3138. Application Parts List Ref Desig Description Q1 MOSFET Q2 MOSFET U1 Controller D3 Diode L1 Inductor L2 Inductor C1,C2,C18,C20 Capacitor, Poscap C3,C4,C6,C12 Capacitor, Ceramic C7 Capacitor, Ceramic C8 Capacitor, Ceramic ...
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... Output Current (A) Figure 14 - Efficiency for IRU3138 Evaluation Board Figure 16 - Shut Down the output by pulling down the soft-start pin Ch1: HDrv, Ch2:LDrv, Ch3: SS pin Figure 18 - Transient response @ Iout=15A Ch1: Output, Ch4:Iout (5A/Div) ...
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... Surface Mount, Narrow Body A B PIN NO. 1 NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. Rev. 1.0 01/29/04 (S) SOIC Package C 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 IRU3138 H L DETAIL ...
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... IRU3138 PACKAGE SHIPMENT METHOD PKG PACKAGE DESIG DESCRIPTION S SOIC, Narrow Body IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 18 PIN PARTS COUNT PER TUBE Feed Direction Figure A This product has been designed and qualified for the consumer market. ...