AAT2500M
400mA Step-Down Converter and 300mA LDO
Functional Block Diagram
IN_BUCK
LX
EN_BUCK
EN_LDO
Bias
PGND
FB_BUCK
VCC
VCC
IN_LDO
OUT_LDO
Oscillator
RLDOFB1
RLDOFB2
AGND
Functional Description
Linear Regulator
The AAT2500M is a high performance power man-
agement IC comprised of a buck converter and a lin-
ear regulator. The buck converter is a high efficien-
cy converter capable of delivering up to 400mA.
Operating at 1.8MHz, the converter requires only
three external power components (CIN, COUT, and
LX) and is stable with a ceramic output capacitor.
The linear regulator delivers 300mA and is also sta-
ble with ceramic capacitors.
The advanced circuit design of the linear regulator
has been specifically optimized for very fast start-
up and shutdown timing. This proprietary LDO has
also been tailored for superior transient response
characteristics. These traits are particularly impor-
tant for applications that require fast power supply
timing.
The high-speed turn-on capability is enabled
through implementation of a fast-start control cir-
10
2500M.2007.06.1.0
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
