DUAL INPUT
LOW DROPOUT REGULATOR
February 26, 1999
EZ1580/EZ1581
EZ1582/EZ1583
APPLICATION INFORMATION
The EZ158X is a low dropout regulator designed to
power the next generation of low voltage, split voltage
plane processors, such as the Pentium® Processor
P55C, the IBM PowerPC™ 603EV and 604EV and the
AMD5
K
86™ and K6 Processors.
The dropout voltage is minimized by utilizing a
separate input voltage, V
CONTROL
, which should exceed
V
OUT
by at least 1.3V. The 2.5V power for the load
(microprocessor core) can be derived from a 3.3V
system supply. Since the efficiency of a linear regulator
is the ratio of the output to the input voltage, heat
dissipation is reduced by using a 3.3 input, thereby
lowering heatsink and cooling fan costs. For a load of
7A at 2.5V, the regulator would dissipate 17.5W when
converting from 5V, but only 5.6W from a 3.3V input.
Remote Kelvin sensing of the output voltage can be
achieved by connecting the sense pin to the output at
the load. Remote sensing will reduce errors
associated with resistive trace losses between
regulator and processor.
DEVICE OUTLINE - TO-220, 5 PIN
DEVICE OUTLINE - TO-263, 5 PIN
MINIMUM LAND PATTERN - TO-263, 5 PIN
5
© 1999 SEMTECH CORP.
652 MITCHELL ROAD NEWBURY PARK CA 91320
SEMTECH [ SEMTECH CORPORATION ]
