AAT2500B Datasheet, PDF (11/21 Pages) Advanced Analogic Technologies – Adjustable 3-Channel Regulator

SystemPower^TM
Functional Block Diagram
FB
PRODUCT DATASHEET
AAT2500B
Adjustable 3-Channel Regulator
VP
VIN
SYNC
EN
VLDOA
ENB
VLDOB
Voltage
Reference
See Note
Err.
Amp.
Control
Logic
Err.
Amp.
Voltage
Reference
DH
Logic
DL
Over-Current
Protection
91%
VREF
See Note
OUTB
See Note
LX
PGND
OUTA
ENA
FBA
POK
FBB
AGND
Note: For adjustable version, the internal feedback divider is omitted and
the FB pin is tied directly to the internal error amplifier.
Functional Description
The AAT2500B is a high performance power manage-
ment 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 effi-
ciency performance. The switching frequency is 2MHz,
minimizing the size of the inductor. The converter
requires only three external components (C_IN, C_OUT, and
L). LDOA can deliver 500mA. LDOA can deliver 150mA.
Each regulator has independent input voltage and enable
pins and operates wth 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 capabil-
ity while maintaining over 90% efficiency at full load. It
consumes 30μA of typical no load quiescent current,
making it also ideal for light load applications. The oscil-
lator operates at 2MHz, minimizing the cost and size of
external components.
A logic low on the EN pin shuts the converter down and
makes it consume less than 1μA of current.
2500B.2008.03.1.0
www.analogictech.com
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