AAT1184 Datasheet, PDF (10/19 Pages) Advanced Analogic Technologies – High Voltage Step-Down Regulator

SwitchReg^TM
Functional Block Diagram
PRODUCT DATASHEET
AAT1184
High Voltage Step-Down Regulator
VINT
VL
Reg.
IN
OT
OSC
FB
COMP
EN
Error
Amp
CCoommpp..
Control
Logic
Voltage
Ref
Logic
20Ω
Comp
VOCP
= 0.1V
BST
LX
RS
OS
GND
Functional Description
The AAT1184 is a high voltage step-down (Buck) regula-
tor with input voltage range from 6.0V to 24.0V, provid-
ing high output current in a small package. The output
voltage is user-programmable from 1.5V to 5.5V. The
device is optimized for low-cost 12V adapter inputs.
The device utilizes voltage mode control configured for
optimum performance across the entire output voltage
and load range.
The controller includes integrated over-current, soft-
start and over-temperature protection. Over-current is
sensed through the output inductor DC winding resis-
tance (DCR). An external resistor and capacitor network
adjusts the current limit according to the DCR of the
inductor and the desired output current limit. Frequency
reduction limits the over-current stress during overload
and short-circuit events. The operating frequency returns
to the nominal setting when over-current conditions are
removed.
The AAT1184 is available in the Pb-free 12-pin TSOPJW
package with rated operating temperature range of
-40°C to 85°C.
10
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1184.2008.07.1.0