US1261 UNISEM, US1261 Datasheet
US1261
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US1261 Summary of contents
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... Voltage Reference Initial Accuracy Built in Thermal Shutdown APPLICATIONS APPLICATIONS Pentium II Processor Applications TYPICAL APPLICATION TYPICAL APPLICATION 3.3V US1261 1261app1-1.3 5V Typical application of US1261 in a Pentium II processor application PACKAGE ORDER INFORMATION PACKAGE ORDER INFORMATION ° 150 Rev. 1.7 3/22/99 DUAL 6A AND 1A LOW DROPOUT POSITIVE FIXED OUTPUT REGULATOR ...
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... US1261 ABSOLUTE MAXIMUM RATINGS ABSOLUTE MAXIMUM RATINGS Input Voltage (Vin) ............................................................. Power Dissipation ............................................ Storage Temperature Range ................................ Operating Junction Temperature Range ...................... 150 C PACKAGE INFORMATION PACKAGE INFORMATION 7 PIN PLASTIC TO220 FRONT VIEW 5 Vout1 4 Vin Gnd 3 Vout2 2 Vctrl 1 =2.7 C/W =60 C ELECTRICAL SPECIFICATIONS ELECTRICAL SPECIFICATIONS Unless otherwise specified ,these specifications apply over ,Cin=1 uF,Cout=100uF,and Tj=0 to 150 C.Typical values refer to Tj=25 C. Ifl=6A for output #2 & ...
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... A high frequency capacitor is connected between this pin and Vin pin to insure stability. BLOCK DIAGRAM BLOCK DIAGRAM Vin 4 Vctrl 1 Figure 1 - Simplified block diagram of the US1261 Rev. 1.7 3/22/99 THERMAL + SHUTDOWN 1.20V 1261blk1-1.1 US1261 ...
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... Stability The US1261 requires the use of an output capacitor as part of the frequency compensation in order to make the regulator stable. Typical designs for the microproces- sor applications use standard electrolytic capacitors with typical ESR in the range 100 m and the output capacitance of 500 to 1000uF ...
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... TO-263 package is a suitable package for our ap- plication. Rev. 1.7 3/22/99 Layout Consideration The US1261 like all other high speed linear regulators need to be properly laid out to insure stable operation. The most important component is the output capacitor, which 300 400 needs to be placed close to the output pin and con- ...
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... US1261 TYPICAL APPLICATION TYPICAL APPLICATION PENTIUM APPLICATION 3.3V US1261 1261app1-1.3 5V Figure 4 - Typical application of US1261 in the Pentium Notes: Pentium is trade mark of Intel Corp. Ref Desig Description U1 Dual LDO Regulator C1,C4 Capacitor C3 Capacitor C2 Capacitor R1 Resistor HS1 Heat Sink 1)Use 1" Square Copper Pad area if Iout2<1.7A & Iout1<0.2A. ...