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.