AAT2146W Datasheet, PDF (8/18 Pages) Skyworks Solutions Inc. – Low-Noise, Fast Transient 600mA Step-Down Converter

DATA SHEET
AAT2146W
Low-Noise, Fast Transient 600mA Step-Down Converter
Functional Block Diagram
OUT
VIN
Err
Am. p
Voltage
Reference
EN
INPUT
DH
Logic
DL
LX
PGND
AGND
Functional Description
The AAT2146W is a high performance, fixed frequency,
600mA, 2MHz, monolithic step-down converter. It has
been designed with the goal of minimizing external com-
ponents, size and optimizing efficiency over the com-
plete load range, and produces reduced ripple voltage
and spectral noise. Typically, a 4.7μH inductor and a
4.7μF ceramic output capacitor are recommended (see
tables 4 and 5).
The adjustable output can be programmed with external
feedback to any voltage, ranging from 0.6V to the input
voltage. An additional feed-forward capacitor (C_FF) can
also be added to the external feedback to provide
improved transient response (see Figure 1).
At dropout, the converter duty cycle increases to 100%
and the output voltage tracks the input voltage minus
the R_DS(ON) voltage drop of the P-channel high-side
MOSFET.
The input voltage range is 2.7V to 5.5V. The converter
efficiency has been optimized for all load conditions,
ranging from no load to 600mA.
The internal error amplifier and compensation provides
excellent transient response, load, and line regulation.
Soft start eliminates any output voltage overshoot when
the enable or the input voltage is applied.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
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202008A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • May 28, 2012