Dual 400mA, 1MHz Step-Down DC-DC Converter
Functional Block Diagram
FB1
VIN1
AAT2510
Err.
Amp.
Comp.
DH
Logic
Voltage
Reference
Control
Logic
LX1
DL
EN1
GND1
SGND1
FB2
See
Note
VIN2
Err.
Amp.
Comp.
DH
Logic
Voltage
Reference
LX2
DL
EN2
See
Note
Control
Logic
GND2
SGND2
Note: Internal resistor divider included for
≥1.2V
versions. For low voltage versions, the feedback pin is tied directly to the error amplifier input.
Operation
Device Summary
The AAT2510 is a constant frequency peak current
mode PWM converter with internal compensation.
Each channel has independent input, enable, feed-
back, and ground pins with non-synchronized
1MHz clocks.
Both converters are designed to operate with an
input voltage range of 2.7V to 5.5V. The output
voltage ranges from 0.6V to the input voltage for
the internally fixed version and up to 2.5V for the
externally adjustable version. The 0.6V fixed model
shown in Figure 1 is also the adjustable version
and is externally programmable with a resistive
divider as shown in Figure 2. The converter MOS-
FET power stage is sized for 400mA load capabili-
ty with up to 96% efficiency. Light load efficiency
exceeds 80% at a 500µA load.
8
2510.2006.05.1.10