US3012CW UNISEM, US3012CW Datasheet
US3012CW
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US3012CW Summary of contents
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... VID1 VID0 Notes: Pentium II and Pentium Pro are trade marks of Intel Corp. PACKAGE ORDER INFORMATION PACKAGE ORDER INFORMATION Device US3012CW US3012ACW Rev. 1.0 5/6/98 DESCRIPTION DESCRIPTION The US3012 family of controller ICs are specifically de- signed to meet Intel specification for Pentium II and Pentium Pro microprocessor applications as well as the next generation P6 family processors ...
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US3012/3012A ABSOLUTE MAXIMUM RATINGS ABSOLUTE MAXIMUM RATINGS V5 supply Voltage ........................................... 7V V12 Supply Voltage ............................................ 20V Storage Temperature Range ................................. -65 TO 150 C Operating Junction Temperature Range .......... 0 TO 125 C PACKAGE INFORMATION PACKAGE INFORMATION 20 PIN ...
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UVLO Section UVLO Threshold-12V UVLO Hysterises-12V UVLO Threshold-5V UVLO Hysterises-5V Error Comparator Section Input bias current Input Offset Voltage Delay to Output Current Limit Section C.S Threshold Set Current C.S Comp Offset Voltage Hiccup Duty Cycle Supply Current Operating Supply ...
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US3012/3012A PIN DESCRIPTIONS PIN DESCRIPTIONS PIN# PIN SYMBOL Pin Description 20 D0 LSB input to the DAC that programs the output voltage. This pin can be pulled up exter- nally by a 10k resistor to either 3. supply. ...
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BLOCK DIAGRAM BLOCK DIAGRAM En V12 UVLO 5Bit DAC, D2 Ctrl Logic D3 D4 Gnd Figure 1 - Simplified block diagram of the US3012/3012A. Rev. 1.0 5/6/98 Enable Vset Enable PWM + Control Vset Slope Enable Comp ...
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... Short O - Open V - See Unisem or Raytheon parts list for the value. * Table also applies to the none "A" version of the part. Note can be replaced with shorting wire of #20 AWG or lower. This elliminates the expensive current sense resistor that otherwise is needed with RC5051. ...
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US3012/3012A and RC5051 Dual Layout Parts List Ref Desig Description Q1 MOSFET Q2 MOSFET L1 Inductor L2 Inductor D1 Diode C11 Capacitor ,Electrolytic C3 Capacitor ,Electrolytic C1 Capacitor ,Electrolytic C2 Capacitor , Ceramic C4 Capacitor , Ceramic C5 Capacitor , ...
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US3012/3012A Application Information Application Information An example of how to calculate the components for the application circuit is given below. Assuming, two sets of output conditions that this regu- lator must meet, a) Vo=2.8V , Io=14.2A, Vo=185mV, Io=14.2A b) Vo=2V ...
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However if the in- ductor is too small , the output ripple current and ripple voltage become too large. One solution to bring the ripple current down is to increase the switching frequency , ...
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US3012/3012A Following the same procedure for the Schottcky diode results in a heatsink with C/W. Although it is possible to select a slightly smaller heatsink, for sim- plicity the same heatsink as the one for the high ...
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Layout Considerations Switching regulators require careful attention to the lay- out of the components, specifically power components since they switch large currents. These switching com- ponents can create large amount of voltage spikes and high frequency harmonics if some of ...