Peak efficiency: 95%
3 MHz fixed frequency operation
Typical quiescent current: 18 μA
Maximum load current: 600 mA
Input voltage: 2.3 V to 5.5 V
Uses tiny multilayer inductors and capacitors
Current mode architecture for fast load and line
100% duty cycle low dropout mode
Internal synchronous rectifier
Internal soft start
Current overload protection
Thermal shutdown protection
Shutdown supply current: 0.2 μA
Supported by ADIsimPower™ design tool
PDAs and palmtop computers
Digital audio, portable media players
Digital cameras, GPS navigation units
Compact, 600 mA, 3 MHz,
Step-Down DC-to-DC Converter
The ADP2108 is a high efficiency, low quiescent current step-
down dc-to-dc converter manufactured in two different
packages. The total solution requires only three tiny external
components. It uses a proprietary, high speed current mode,
constant frequency PWM control scheme for excellent stability
and transient response. To ensure the longest battery life in
portable applications, the ADP2108 has a power save mode that
reduces the switching frequency under light load conditions.
The ADP2108 runs on input voltages of 2.3 V to 5.5 V, which
allows for single lithium or lithium polymer cell, multiple alkaline
or NiMH cell, PCMCIA, USB, and other standard power sources.
The maximum load current of 600 mA is achievable across the
input voltage range.
The ADP2108 is available in fixed output voltages of 3.3 V, 3.0 V,
2.5 V, 2.3 V, 1.82 V, 1.8 V, 1.5 V, 1.3 V, 1.2 V, 1.1 V, and 1.0 V. All
versions include an internal power switch and synchronous rect-
ifier for minimal external part count and high efficiency. The
ADP2108 has an internal soft start and is internally compensated.
During logic controlled shutdown, the input is disconnected
from the output and the ADP2108 draws less than 1 μA from
the input source.
Other key features include undervoltage lockout to prevent deep
battery discharge and soft start to prevent input current over-
shoot at startup. The ADP2108 is available in 5-ball WLCSP and
5-lead TSOT packages. The ADP2109 provides the same features
and operations as the ADP2108 and has the additional function
of a discharge switch in the WLCSP package.
TYPICAL APPLICATIONS CIRCUIT
2.3V TO 5.5V
1µH 1.0V TO 3.3V
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 ©2008–2014 Analog Devices, Inc. All rights reserved.