US1261
DUAL 6A AND 1A LOW DROPOUT POSITIVE FIXED OUTPUT REGULATOR FEATURES
Guaranteed to provide 1.5V and 2.5V Supplies with 3.1V input. Fast Transient Response 1% Voltage Reference Initial Accuracy Built in Thermal Shutdown
DESCRIPTION
The US1261 product using a proprietary process combines a dual low dropout regulators with fixed outputs of 1.5V and 2.5V in a single package with the 1.5V output having a minimum of 6A and the 2.5V having a 1A output current capability. This product is specifically designed to provide well regulated supplies from 3.3V to generate 1.5V for GTL+ termination resistor supply and 2.5V clock supply for the new generation of the Pentium II processor applications.
APPLICATIONS
Pentium II Processor Applications
TYPICAL APPLICATION
3.3V
C1
Vout1 Vin
5 4 3 2 1
C4 C2 C3
2.5V / 1A
US1261
Gnd Vout2 Vctrl
1.5V / 6A
1261app1-1.3
5V
R1
Typical application of US1261 in a Pentium II processor application
PACKAGE ORDER INFORMATION
Tj (°C) 0 TO 150 5 PIN PLASTIC TO220(T) US1261CT 5 PIN PLASTIC TO263(M) US1261CM 5 PIN PLASTIC POWER FLEX(P) US1261CP
Rev. 1.7 3/22/99
3-1
US1261
ABSOLUTE MAXIMUM RATINGS
Input Voltage (Vin) ............................................................. 10V Power Dissipation ............................................ Internally Limited Storage Temperature Range ................................ -65°C TO 150°C Operating Junction Temperature Range ...................... 0°C TO 150°C
PACKAGE INFORMATION
7 PIN PLASTIC TO220
FRONT VIEW 5 4 3 2 1
7 PIN PLASTIC TO263
FRONT VIEW 5 4 3 2 1
7 PIN POWER FLEX (P)
FRONT VIEW 5 4 3 2 1
Vout1 Vin Gnd Vout2 Vctrl
Vout1 Vin Gnd Vout2 Vctrl
Vout1 Vin Gnd Vout2 Vctrl
θJT =2.7°C/W θJA =60°C/W
θJA =30°C/W for 1"sq pad
θJA =30°C/W for 1"sq pad
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 & 1A for output #1.Vctrl=5V,Vin=3.3V. PARAMETER SYM TEST CONDITION MIN TYP MAX UNITS Vctrl Input Voltage 3.0 V Output Voltage #2 Vo2 Io=10mA, Tj=25°C 1.485 1.500 1.515 V Io=10mA 1.470 1.500 1.530 Output Voltage #1 Vo1 Io=10mA, Tj=25°C 2.462 2.500 2.537 V Io=10mA 2.425 2.500 2.575 Line Regulation Io=10mA, 3.1V