FEATURES
· 150-mA LDO
· Available in 1.5-V, 1.6-V, 1.8-V Fixed-Output
and Adjustable (1.2-V to 2.5-V) Versions
· Low Input Voltage Requirement (Down to
1.8 V)
· Small Output Capacitor, 0.1-μF
· Dropout Voltage Typically 200 mV at 150 mA
· Less Than 1 μA Quiescent Current in
Shutdown Mode
· Thermal Protection
· Over Current Limitation
· 5-Pin SOT-23 (DBV) Package

APPLICATIONS
· Portable Communication Devices
· Battery Powered Equipment
· PCMCIA Cards
· Personal Digital Assistants
· Modems
· Bar Code Scanners
· Backup Power Supplies
· SMPS Post Regulation
· Internet Audio

DESCRIPTION
The TPS721xx family of LDO regulators is available
in fixed voltage options that are commonly used to
power the latest DSPs and microcontrollers with an
adjustable option ranging from 1.22 V to 2.5 V. These regulators can be used in a wide variety of
applications ranging from portable, battery-powered
equipment to PC peripherals. The family features
operation over a wide range of input voltages (1.8 V
to 5.5 V) and low dropout voltage (150 mV at full load). Therefore, compared to many other regulators
that require 2.5-V or higher input voltages for
operation, these regulators can be operated directly
from two AAA batteries. Also, the typical quiescent
current (ground pin current) is low, starting at 85 μA during normal operation and 1 μA in shutdown mode.
These regulators can be operated very efficiently and,
in a battery-powered application, help extend the
longevity of the device.
Similar LDO regulators require 1-μF or larger output
capacitors for stability. However, this regulator uses
an internal compensation scheme that stabilizes the
feedback loop over the full range of input voltages
and load currents with output capacitances as low as
0.1-μF. Ceramic capacitors of this size are relatively
inexpensive and available in small footprints.
This family of regulators is particularly suited as a
portable power supply solution due to its minimal
board space requirement and 1.8-V minimum input
voltage. Being able to use two off-the-shelf AAA
batteries makes system design easier and also
reduces component cost. Moreover, the solution will
be more efficient than if a regulator with a higher
input voltage is used.