AAT3221 Datasheet, PDF (8/16 Pages) Advanced Analogic Technologies – 150mA NanoPower™ LDO Linear Regulator

AAT3221/2
150mA NanoPower™ LDO Linear Regulator
Functional Block Diagram
IN
OUT
Over-Current
Protection
Over-Temp
Protection
EN
V_REF
GND
Functional Description
The AAT3221 and AAT3222 are intended for LDO
regulator applications where output current load
requirements range from No Load to 150mA. The
advanced circuit design of the AAT3221/2 has been
optimized for very low quiescent or ground current
consumption making it ideal for use in power man-
agement systems for small battery operated
devices. The typical quiescent current level is just
1.1µA. The AAT3221/2 also contains an enable cir-
cuit, which has been provided to shutdown the LDO
regulator for additional power conservation in
portable products. In the shutdown state the LDO
draws less than 1µA from input supply.
The LDO also demonstrates excellent power sup-
ply ripple rejection (PSRR), and load and line tran-
sient response characteristics. The AAT3221/2 is a
truly high performance LDO regulator especially
well suited for circuit applications which are sensi-
tive to load circuit power consumption and extend-
ed battery life.
The LDO regulator output has been specifically
optimized to function with low cost, low ESR
ceramic capacitors. However, the design will allow
for operation with a wide range of capacitor types.
The AAT3221/2 has complete short circuit and
thermal protection. The integral combination of
these two internal protection circuits give the
AAT3221/2 a comprehensive safety system to
guard against extreme adverse operating condi-
tions. Device power dissipation is limited to the
package type and thermal dissipation properties.
Refer to the thermal considerations section for
details on device operation at maximum output
load levels.
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3221.2002.03.0.94