IRU3037 IRF [International Rectifier], IRU3037 Datasheet
IRU3037
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IRU3037 Summary of contents
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... Rev. 2.8 03/10/03 8-PIN SYNCHRONOUS PWM CONTROLLER DESCRIPTION The IRU3037 controller IC is designed to provide a low cost synchronous Buck regulator for on-board converter applications. With the migration of today’s ASIC products requiring low supply voltages such as 1.8V and lower, together with currents in excess of 3A, traditional linear regulators are simply too lossy to be used when input supply even in some cases with 3 ...
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... Comp 2 7 LDrv Gnd HDrv 4 5 =160 C/W JA TEST CONDITION MIN IRU3037 1.225 IRU3037A 0.784 5<Vcc<12 Supply Ramping Up 4.0 Supply Ramping Up 3.1 Fb Ramping Down (IRU3037) 0.4 (IRU3037A) 0.3 Freq=200KHz, C =1500pF 2 L Freq=200KHz, C =1500pF 2 L SS=0V 1 SS=0V 0.5 SS=0V -10 www.irf.com =0 to 70°C. Typical values refer A TYP MAX UNITS 1 ...
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... The converter can be shutdown by pulling this pin below 0.5V. Rev. 2.8 03/10/03 TEST CONDITION SS=3V, Fb=1V SS=0V, Fb=1V m IRU3037 IRU3037A C =1500pF =1500pF Fb=1V, Freq=200KHz Fb=1.5V www.irf.com IRU3037 / IRU3037A MIN TYP MAX UNITS mA -0.1 mA -64 mmho 600 830 410 180 200 220 KHz 400 440 345 1.275 V 1 ...
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... The outputs are protected against the short-circuit. The IRU3037 protects the circuit for shorted output by sens- ing the output voltage (through the external resistor di- vider). The IRU3037 shuts down the PWM signals, when the output voltage drops below 0.6V (0.4V for IRU3037A). The IRU3037 also protects the output from over-voltaging when the control FET is shorted ...
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... Output voltage is programmed by reference voltage and external voltage divider. The Fb pin is the inverting input of the error amplifier, which is internally referenced to 1.25V (0.8V for IRU3037A). The divider is ratioed to pro- vide 1.25V at the Fb pin when the output is at its desired value. The output voltage is defined by using the follow- ...
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... This will result to a ripple approximately 14% of output cur- rent. Power MOSFET Selection The IRU3037 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 ), maximum output current, On- ...
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... By using equation (6), we can calculate the switching losses 0.186W SW Feedback Compensation The IRU3037 is a voltage mode controller; the control loop is a single voltage feedback path including error amplifier and error comparator. To achieve fast transient (Lower Switch) CON response and accurate output regulation, a compensa- tion circuit is necessary ...
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... IRU3037 / IRU3037A 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 (15) and calculate www.irf.com IRU3037 / IRU3037A 2p3R ...
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... The IC's power dissipation results to an exces- sive temperature rise. This should be considered when using IRU3037A for such application. 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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... Rev. 2.8 03/10/03 IRU3037 / IRU3037A IRU3037A Vcc vs. Icc @470PF, 1150PF and 1540PF Gate Load C =1540pF LOAD Vcc (V) Figure 9 - Vcc vs. Icc IRU3037A Vc vs. Ic @470PF, 1150PF and 1540PF Gate Load C =1540pF LOAD ...
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... IRU3037 / IRU3037A TYPICAL PERFORMANCE CHARACTERISTICS Min -40°C 0 ° ° Figure 11 - Output Voltage 92 ...
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... ° ° ° ° IRU3037 / IRU3037A Rise Time / Fall Time CL = 1500pF 0°C +25°C +50°C +75°C +100°C ...
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... C3 C4 1uF 1uF Vcc Vc HDrv U1 SS/SD C8 IRU3037 0.1uF LDrv Comp C9 Fb 680pF Gnd R4 105K Figure 18 - Typical application of IRU3037 in an on-board DC-DC converter 14 D1 1N4148 D2 1N4148 C2 2x 10TPB100ML, C5 100uF, 55m V 0.1uF Q1 1/2 of IRF7301 D05022P-103, 10uH, 4.3A Q2 1/2 of IRF7301 R6 1.65K 1K, 1% using a single 5V supply. ...
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... Vcc HDrv U2 SS/SD C13 IRU3037 LDrv 0.1uF Comp C14 Fb 2200pF Gnd R5 14K Figure 19 - Typical application of IRU3037 or IRU3037A in an on-board DC-DC converter providing the Core, GTL+, and Clock supplies for the Pentium II microprocessor. Rev. 2.8 03/10/03 L1 1uH C2 10TPB100M, 100uF, C1 55m V , 1.5A rms 1uF Q1 1/2 of IRF7752 L2 CTX5-2P, 3.5uH @ 2.5A ...
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... IRU3037 / IRU3037A TYPICAL APPLICATION 1.8V to 7.5V / 0.5A Boost Converter Vpwr (1.5V Min) Vc/Vcc R1 20K Q2 R2 C10 2N2222 10K 100pF Q1 2N2222 R3 20K Figure 20 - Typical application of IRU3037 as a boost converter 1uH (CoilTronics UP2B-1R0 68uF C5 1uF C4 C5 0.01uF 0.1uF R4 SS/SD Comp Vc HDrv 25K U1 IRU3037 Fb Vcc LDrv Gnd ...
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... D4 C1 LL4148 33uF 16V Gnd Vcc C8 1uF SS/SD U1 IRU3037 C5 0.1uF Comp C4 2200pF Gnd R3 20K Figure 21 - Demo-board application of IRU3037. Application Parts List Ref Desig Description Q1 MOSFET Q2 MOSFET U1 Controller D1, D2, D4 Diode L1 Inductor L2 Inductor C1 Capacitor, Tantalum C2A, C2B Capacitor, Poscap C9B, C9C Capacitor, Poscap ...
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... IRU3037 / IRU3037A DEMO-BOARD WAVEFORMS V =5.0V, V =3.3V IN OUT 100 Output Current (A) Figure 22 - Efficiency for IRU3037 Evaluation Board. Vss IRU3037 V OUT OUT Figure 24 - Shutdown the output by pulling down the soft-start. IRU3037 2A 0A Figure 26 - Transient response @ I 18 IRU3037 ...
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... A 1.0 DIA E F PIN NUMBER 1 G NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. Rev. 2.8 03/10/03 IRU3037 / IRU3037A (F) TSSOP Package 8-Pin DETAIL 8-PIN SYMBOL 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 2.90 3.00 3.10 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 ...
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... IRU3037 / IRU3037A 8-Pin Surface Mount, Narrow Body PIN NO NOTE: ALL MEASUREMENTS ARE IN MILLIMETERS. 20 (S) SOIC Package DETAIL-A 0.38 6 0.015 8-PIN SYMBOL MIN MAX A 4.80 4.98 B 1.27 BSC 0.53 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 H L DETAIL-A ...
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... PIN PARTS COUNT PER TUBE 8 100 Visit us at www.irf.com for sales contact information Data and specifications subject to change without notice. 02/01 www.irf.com IRU3037 / IRU3037A PARTS T & R PER REEL Orientation 2500 Fig A 2500 Fig Feed Direction Figure B TAC Fax: (310) 252-7903 ...