PRODUCT DATASHEET
AAT2503178
SystemPowerTM
Adjustable 3-Channel Regulator
Functional Block Diagram
FB
VIN
VP
Voltage
Reference
DH
Err.
Amp.
LX
MODE/SYNC
Logic
Control
Logic
DL
PGND
OUTA
EN
VLDOA
ENB
VLDOB
ENA
Err.
Amp.
Voltage
Reference
FBA
POK
90%
VREF
OUTB
FBB
AGND
Switch-Mode Step-Down Converter
Functional Description
The switching regulator is a monolithic step-down con-
verter operating with input voltage range of 2.7V to 5.5V.
Power devices are sized for 800mA current capability and
achieve over 95% efficiency. PFM operation maintains
high efficiency under light load conditions (typically
<50mA). The MODE/SYNC pin allows an optional “PWM
Only” mode. This maintains constant frequency and low
output ripple across all load conditions. Alternatively, the
IC can be synchronized to an external clock via the
MODE/SYNC input. External synchronization is main-
The AAT2503 is a high performance power management
IC comprised of a step-down converter and two linear
regulators. The step-down converter operates in both
fixed and variable frequency modes for high efficiency
performance. The switching frequency is 2MHz, minimiz-
ing the size of the inductor. The converter requires only
three external components (CIN, COUT, and L). The LDOs
can deliver up to 150mA each. Each regulator has inde-
pendent input voltage and enable pins and operates with
ceramic capacitors.
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ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
