US3034 ETC-unknow, US3034 Datasheet
US3034
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US3034 Summary of contents
Page 1
... PIN PWM SWITCHER DESCRIPTION DESCRIPTION The US3034 IC provides an 8 pin low cost switching controller with true short circuit protection all in a compact 8 pin surface mount package, providing a low cost switching solution for dual supply processor applications that require switching regulator for the 3.3V supply such as the applications with AGP on board ...
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... US3034 ABSOLUTE MAXIMUM RATINGS ABSOLUTE MAXIMUM RATINGS V Supply Voltages ............................................................. 20V 12 F.B Pin Voltages........................................................ Storage Temperature Range ................................. -65 TO 150 C Operating Junction Temperature ............................... 0 TO 150 C PACKAGE INFORMATION PACKAGE INFORMATION 8 PIN PLASTIC SOIC (S) TOP VIEW Drv V12 CS Vfb 3 6 CS- Vhyst 4 5 Gnd =160 C/W ...
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... BLOCK DIAGRAM BLOCK DIAGRAM V12 Vhyst 2 4 Drv 1 Gnd 5 Figure 1 - Simplified block diagram of the US3034 Rev. 1.8 1/13/99 Vfb 3 5V Reg R UVLO 20uA PWM Control 1.25V Vref 3R S ...
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... C1 C2 Figure2- Typical application of US3034 in a flexible motherboard with the 4 bit VID output voltage selection. This circuit is done using a dual layout with the US3033 part . The advantage of this circuit is that it uses a single jumper that programs the output voltage in 16 steps with 0.1V steps from 2V to 3.5V, designed for Intel P55,P54 AMD K5 & well as Cyrix M1 and M2 applications. ...
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... Pentium Core Supply Application Parts List (US3034 and US3033 Dual Layout) Low Cost 4 Bit VID Ref Desig Description Qty U1 LDO/Switcher MOSFET 1 D1 Schottky Diode 1 L2 Inductor 1 L1 Inductor 1 R1 Resistor 1 R2 Resistor 1 R3 Resistor 1 R4A * Resistor 1 R4B * Resistor 1 R5A Resistor ...
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... C1 Figure4- The circuit in figure 4 is the application of the US3034 which is done using a dual layout with US3033 in a switching mode only. This circuit can be used to generate a low cost 5V to 3.3V for either Pentium application with AGP socket or in Pentium II applications where it is desirable to generate an accurate on board 3.3V supply. ...
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... Drv V12 Vfb Vhyst Part # US3034CS ( 8 pin SOIC) IRL3303 (TO263) PBYR735(Axial Thr Hole pkg) PBYR1035B(SMT, TO263 pkg) Core:T50-18,L=4 uH Turns: 7T, 18 AWG L ohm,5%, SMT 182 kohm,1%, SMT 1 kohm,1%, SMT 576ohm,1%, SMT 3.83 kohm,1%, SMT 1 kohm,1% , SMT 470uF, Elect 6MV1000GX, 1000uF,6 ...
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... I/O supply requires this regulator to also be a switching regulator such as the motherboard applica- tions with AGP slot or the Pentium II with on board 5V to 3.3V converter. The US3034 provides an easy and low cost switching regulator solution for Vcore and 3.3V supplies with true short circuit protection. ...
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... Where: Rb=Bottom resistor of the divider X= ( Vo/2))/Vref - 1 Vref=1.25 V typ. X= (3.38+ (0.044/2))/1. 1.72 Rb=1000/1.72=580 Select Rb=576 , 1% Frequency Calculation The US3034 frequency of operation is calculated using the following formula: Fs= (Vo*(1-D)*ESR) /(L* Vo) (MHz) Where: Vo=Output voltage (V) D=Duty cycle ESR=Output capacitor ESR (V) L=Output inductance (uH) Vo=Output ripple voltage (V) ...