Datasheet LT1581, LT1581-2.5 (Analog Devices)

LT1581/LT1581-2.5 10A, Very Low Dropout Regulators
U FEATURES DESCRIPTION
■
Low Dropout, 430mV at 10A Output Current
The LT ®1581 is a 10A low dropout regulator designed to ■
Fast Transient Response
power the new generation of microprocessors. The drop- ■
Remote Sense
out voltage of this device is 100mV at light loads rising to ■ 1mV Load Regulation just 430mV at 10A. To achieve this dropout a second low ■ Fixed 2.5V Output and Adjustable Output current input voltage 1V greater than the output voltage is ■ No Supply Sequencing Problems in required. The device can also be used as a single supply Dual Supply Mode device where dropout is comparable to an LT1584. Several other new features have been added to the LT1581.
U APPLICATIONS
A remote SENSE pin is brought out. This feature virtually eliminates output voltage variations due to load changes. ■ Microprocessor Supplies Typical load regulation for a load current step of 100mA to ■ Post Regulators for Switching Supplies 10A, measured at the SENSE pin, is less than 1mV. ■ High Current Regulators ■ The LT1581 has fast transient response, equal to the 5V to 3.XXV for Pentium® Processors Operating LT1584. On fixed voltage devices, the ADJUST pin is at 90MHz to 166MHz and Beyond ■ brought out. A small capacitor on the ADJUST pin further 3.3V to 2.9V for Portable Pentium Processor ■ improves transient response. PowerPCTM Series Power Supplies This device is ideal for generating processor supplies of 2V to 3V on motherboards where both 5V and 3.3V supplies are available. , LTC and LT are registered trademarks of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation. PowerPC is a trademark of IBM Corporation.
U TYPICAL APPLICATION Dropout Voltage – 2.5V Microprocessor Supply Minimum Power Voltage
0.8 INDICATES GUARANTEED TEST POINTS 2.5V/10A 3.3V 0.7 POWER OUTPUT 10A + + 100µF TANT 0.6 330µF AVX TPS OS-CON ) (V) LT1581-2.5 × 7 0.5 DATA SHEET LIMIT OUT – V 0.4 5V CONTROL SENSE 0.2A + 0.3 GND ADJ POWER 10µF T (V J = 125°C TANT 0.2 TJ = 25°C 0.1µF 1581 TA01 MINIMUM POWER VOLTAGE (V) 0.1 0 0 1 2 3 4 5 6 7 8 9 10 OUTPUT CURRENT (A) 1581 G03 1