spx1580 Exar Corporation, spx1580 Datasheet - Page 3

• Manufacturer Part Number: spx1580
• Description: 7a Ultra Dropout Voltage Regulator
• Manufacturer: Exar Corporation

Note that TAB is internally connected to Pin 3.
The SPX1580 is designed as a high performance
and low cost solution for application requiring a
lower dropout than traditional NPN regulators.
The SPX1580 uses a separate input voltage V
( V
voltage. This allows the 2.5V power for the load
to come from a 3.3V system supply.
As added benefit this will reduce the heat dissi-
pation*, and lower heatsink and cooling fan cost.
Date: 5/16/04
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A typical application would use 3.3V for V
and 5.0V for V
supply to provide a nominal 2.5V output. Using
the sense pin allows Kelvin measure the output,
reducing resistance-associated errors.
The SPX1580 can power the 2.5V core voltage
for microprocessors such as a PentiumPC
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