AAT2503 Datasheet, PDF (12/22 Pages) Advanced Analogic Technologies – Adjustable 3-Channel Regulator

Functional Block Diagram
FB
DATA SHEET
AAT2503
Adjustable Three-Channel Regulator
VIN
VP
MODE/SYNC
EN
VLDOA
ENB
VLDOB
Voltage
Reference
Err.
Amp.
Control
Logic
DH
Logic
DL
OUTB
Err.
Amp.
Voltage
Reference
90%
VREF
LX
PGND
OUTA
ENA
FBA
POK
FBB
AGND
Functional Description
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 (C_IN, C_OUT, 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.
Switch-Mode Step-Down Converter
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-
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202016B • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • March 19, 2013