AAT1110 AAT, AAT1110 Datasheet - Page 9

• Manufacturer Part Number: AAT1110
• Description: Fast Transient 800mA Step-Down Converter
• Manufacturer: AAT

Functional Block Diagram
Functional Description
The AAT1110 is a high performance 800mA 1.4MHz
monolithic step-down converter. It has been
designed with the goal of minimizing external com-
ponent size and optimizing efficiency over the com-
plete load range. Apart from the small bypass input
capacitor, only a small L-C filter is required at the out-
put. Typically, a 4.7µH inductor and a 4.7µF ceramic
capacitor are recommended (see table of values).
The fixed output version requires only three external
power components (C
adjustable version can be programmed with external
feedback to any voltage, ranging from 0.6V to the
input voltage. An additional feed-forward capacitor
1110.2006.04.1.0
EN
Note: For adjustable version, the internal feedback divider is omitted and the OUT pin is tied directly
to the internal error amplifier.
IN
Reference
, C
Voltage
INPUT
OUT
, and L). The
Amp
Err
See note
.
Fast Transient 800mA Step-Down Converter
OUT
can also be added to the external feedback to pro-
vide improved transient response (see Figure 1).
At dropout, the converter duty cycle increases to
100% and the output voltage tracks the input volt-
age minus the R
side MOSFET.
The input voltage range is 2.7V to 5.5V. The con-
verter efficiency has been optimized for all load
conditions, ranging from no load to 800mA.
The internal error amplifier and compensation pro-
vides excellent transient response, load, and line
regulation. Soft start eliminates any output voltage
overshoot when the enable or the input voltage is
applied.
Logic
DH
DL
DSON
drop of the P-channel high-
VIN
LX
PGND
AGND
AAT1110
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